$ 3,460,200

$ 3,657,600

$ 3,800,400

$ 3,116,400

$ 3,501,700

$ 3,788,000

$ 3,829,000

$ 3,244,200

$ 14,034,600

$ 14,362,900

$ 12,826,600

559,300

541,300

514,900

152,200

134,000

116,900

144,600

136,200

141,200

2,100

2,000

1,800

13,766,300

14,087,100

12,539,400

100

50,400

0

100

(1,100)

(3,900)

268,500

325,100

283,300

3,200

1,500

1,300

(54,900)

(52,900)

(46,700)

(14,800)

0

400

200

2,200

(66,100)

(51,200)

(43,200)

61,900

91,300

43,300

5,900

100,500

57,000

69,100

47,300

202,400

273,900

240,100

47,600

60,300

(5,200)

Basic and Diluted Earnings Per Common Share:

$ 47,600

$ 69,200

$ 32,700

$ 5,300

$ 77,500

$ 45,000

$ 51,800

$ 39,300

$ 154,800

$ 213,600

$ 245,300

Basic (in dollars per share)

$ 1.56

$ 2.20

$ 1.02

$ 0.16

$ 2.40

$ 1.40

$ 1.59

$ 1.17

$ 4.90

$ 6.54

$ 6.85

Diluted (in dollars per share)

$ 1.54

$ 2.18

$ 1.01

$ 0.16

$ 2.38

$ 1.38

$ 1.58

$ 1.16

$ 4.86

$ 6.48

$ 6.78

Weighted-average shares outstanding (in thousands):

Basic (in shares)

31,594

32,674

35,816

Diluted (in shares)

31,858

32,983

36,156

Supplemental information:

Excise taxes

$ 1,933,300

$ 1,838,900

$ 1,973,100

Petroleum product sales

^[1]

11,373,800

11,858,400

10,287,900

^[1]

10,707,400

11,251,100

9,773,200

Merchandise

2,620,100

2,423,000

2,372,700

2,200,700

2,022,500

1,991,400

Other operating revenues

Revenue from Contract with Customer [Abstract]

$ 40,700

$ 81,500

$ 166,000

[1]	Years Ended December 31,(Millions of dollars except per share amounts)2019 2018 2017 Supplemental information: 1 Includes excise taxes of:$1,933.3 $1,838.9 $1,973.1

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 154.8	$ 213.6	$ 245.3
Other comprehensive income (loss), net of tax
Initial fair value	(0.1)	0.0	0.0
Realized gain (loss)	0.2	0.0	0.0
Unrealized gain (loss)	1.0	0.0	0.0
Reclassified to interest expense	(0.2)	0.0	0.0
Total	0.9	0.0	0.0
Deferred income tax expense	0.2	0.0	0.0
Other comprehensive income (loss)	0.7	0.0	0.0
Comprehensive income (loss)	$ 155.5	$ 213.6	$ 245.3

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net income	$ 154,800	$ 213,600	$ 245,300
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	152,200	134,000	116,900
Deferred and noncurrent income tax charges (benefits)	23,700	37,900	(50,400)
Loss on early debt extinguishment	14,800	0	0
Accretion of asset retirement obligations	2,100	2,000	1,800
Pretax (gains) losses from sale of assets	(100)	1,100	3,900
Net decrease (increase) in noncash operating working capital	(48,700)	2,300	(36,900)
Other operating activities - net	14,500	7,800	3,000
Net cash provided by operating activities	313,300	398,700	283,600
Investing Activities
Property additions	(204,800)	(204,300)	(258,300)
Proceeds from sale of assets	2,500	1,200	900
Other investing activities - net	(800)	(6,000)	(4,700)
Net cash required by investing activities	(203,100)	(209,100)	(262,100)
Financing Activities
Purchase of treasury stock	(165,800)	(144,400)	(206,000)
Repayments of debt	(573,400)	(21,300)	(131,400)
Borrowings of debt	743,800	0	338,800
Early debt extinguishment costs	(10,400)	0	0
Debt issuance costs	(4,100)	0	(1,100)
Amounts related to share-based compensation	(4,500)	(9,400)	(5,600)
Net cash required by financing activities	(14,400)	(175,100)	(5,300)
Net change in cash, cash equivalents, and restricted cash	95,800	14,500	16,200
Cash, cash equivalents, and restricted cash at January 1	184,500	170,000	153,800
Cash, cash equivalents, and restricted cash at December 31	280,300	184,500	170,000
Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash, cash equivalents, and restricted cash	$ 280,300	$ 170,000	$ 170,000

Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	APIC	Retained Earnings	AOCI
Balance at Dec. 31, 2016	$ 697.0	$ 0.5	$ (608.0)	$ 555.3	$ 749.2	$ 0.0
Balance (in shares) at Dec. 31, 2016		46,767,164
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	245.3				245.3
Purchase of treasury stock	(206.0)		(206.0)
Issuance of common stock	0.0	$ 0.0
Issuance of treasury stock	0.1		7.5	(7.4)
Amounts related to share-based compensation	(5.6)			(5.6)
Share-based compensation expense	7.6			7.6
Balance at Dec. 31, 2017	738.4	$ 0.5	(806.5)	549.9	994.5	0.0
Balance (in shares) at Dec. 31, 2017		46,767,164
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	213.6				213.6
Purchase of treasury stock	(144.4)		(144.4)
Issuance of common stock	0.0	$ 0.0
Issuance of treasury stock			10.6	(10.6)
Amounts related to share-based compensation	(9.4)			(9.4)
Share-based compensation expense	9.1			9.1
Balance at Dec. 31, 2018	$ 807.3	$ 0.5	(940.3)	539.0	1,208.1	0.0
Balance (in shares) at Dec. 31, 2018	46,767,164	46,767,164
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 154.8				154.8
Gain on interest rate hedge, net of tax	0.7					0.7
Purchase of treasury stock	(165.8)		(165.8)
Issuance of common stock	0.0	$ 0.0
Issuance of treasury stock			6.3	(6.3)
Amounts related to share-based compensation	(4.5)			(4.5)
Share-based compensation expense	10.5			10.5
Balance at Dec. 31, 2019	$ 803.0	$ 0.5	$ (1,099.8)	$ 538.7	$ 1,362.9	$ 0.7
Balance (in shares) at Dec. 31, 2019	46,767,164	46,767,164

Description of Business and Basis of Presentation	12 Months Ended
Description of Business and Basis of Presentation	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation The business of Murphy USA Inc. and its subsidiaries (“Murphy USA” or the “Company”) primarily consists of the U.S. retail marketing business that was separated from its former parent company, Murphy Oil Corporation (“Murphy Oil”), plus other assets, liabilities and operating expenses of Murphy Oil that were associated with supporting the activities of the U.S. retail marketing operations. Murphy USA was incorporated in March 2013. The separation was approved by the Murphy Oil board of directors on August 7, 2013, and was completed on August 30, 2013 through the distribution of 100% of the outstanding capital stock of Murphy USA to holders of Murphy Oil common stock on the record date of August 21, 2013. Following the separation, Murphy USA is an independent, publicly traded company, and Murphy Oil retains no ownership interest in Murphy USA. Murphy USA markets refined products through a network of retail gasoline stores and unbranded wholesale customers. Murphy USA’s owned retail stores are almost all located in close proximity to Walmart stores in 26 states and use the brand name Murphy USA®. Murphy USA also markets gasoline and other products at standalone stores under the Murphy Express brand. At December 31, 2019, Murphy USA had a total of 1,489 Company stores. The Company also has certain product supply and wholesale assets, including product distribution terminals and pipeline positions.

Significant Accounting Policies	12 Months Ended
Significant Accounting Policies	Dec. 31, 2019
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies PRINCIPLES OF CONSOLIDATION – These consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and include the accounts of Murphy USA Inc. and its subsidiaries for all periods presented. All significant intercompany accounts and transactions within the consolidated financial statements have been eliminated. REVENUE RECOGNITION – Revenue is recognized when obligations under the terms of a contract with our customers are satisfied; generally, this occurs with the transfer of control of our petroleum products, convenience merchandise, Renewable Identification Numbers ("RINs") and other assets to our third-party customers. Revenue is measured as the amounts of consideration we expect to receive in exchange for transferring goods or providing services. Excise and sales tax that we collect where we have determined we are the principal in the transaction have been recorded as revenue on a jurisdiction-by-jurisdiction basis. The Company enters into buy/sell and similar arrangements when petroleum products are held at one location but are needed at a different location. The Company often pays or receives funds related to the buy/sell arrangement based on location or quality differences. The Company accounts for such transactions on a net basis in its Consolidated Income Statements. See Note 3 "Revenues" for additional information. SHIPPING AND HANDLING COSTS – Costs incurred for the shipping and handling of motor fuel are included in Petroleum product cost of goods sold in the Consolidated Income Statements. Costs incurred for the shipping and handling of convenience store merchandise are included in Merchandise cost of goods sold in the Consolidated Income Statements. TAXES COLLECTED FROM CUSTOMERS AND REMITTED TO GOVERNMENT AUTHORITIES – Excise and other taxes collected on sales of refined products and remitted to governmental agencies are included in operating revenues and operating expenses in the Consolidated Income Statements. Excise taxes on petroleum products collected and remitted were $1.9 billion in 2019, $1.8 billion in 2018, and $2.0 billion in 2017. CASH EQUIVALENTS – Short-term investments, which include government securities, money market funds and other instruments with government securities as collateral, that have a maturity of three months or less from the date of purchase are classified as cash equivalents. ACCOUNTS RECEIVABLE – The Company’s accounts receivable are recorded at the invoiced amount and do not bear interest. The accounts receivable primarily consists of amounts owed to the Company from credit card companies and by customers for wholesale sales of refined petroleum products. The allowance for doubtful accounts is the Company’s best estimate of the amount of probable credit losses on these receivables. The Company reviews this allowance for adequacy at least quarterly and bases its assessment on a combination of current information about its customers and historical write-off experience. Any trade accounts receivable balances written off are charged against the allowance for doubtful accounts. The Company has not experienced any significant credit-related losses in the past three years. INVENTORIES – Inventories of most finished products are valued at the lower of cost, generally applied on a last-in, first-out (“LIFO”) basis, or market. Any increments to LIFO inventory volumes are valued based on the first purchase price for these volumes during the year. Merchandise inventories held for resale are carried at average cost. Materials and supplies are valued at the lower of average cost or estimated value. VENDOR ALLOWANCES AND REBATES – Murphy USA receives payments for vendor allowances, volume rebates and other related payments from various suppliers of its convenience store merchandise. Vendor allowances for price markdowns are credited to merchandise cost of goods sold during the period the related markdown is recognized. Volume rebates of merchandise are recorded as reductions to merchandise cost of goods sold when the merchandise qualifying for the rebate is sold. Slotting and stocking allowances received from a vendor are recorded as a reduction to cost of sales over the period covered by the agreement. PROPERTY, PLANT AND EQUIPMENT – Additions to property, plant and equipment, including renewals and betterments, are capitalized and recorded at cost. Certain marketing facilities are primarily depreciated using the composite straight-line method with depreciable lives ranging from 16 to 25 years. Gasoline stations, improvements to gasoline stations and other assets are depreciated over 3 to 50 years by individual unit on the straight-line method. The Company capitalizes interest costs as a component of construction in progress on individually significant projects based on the weighted average interest rates incurred on its long-term borrowings. Total interest cost capitalized in 2019 was $1.4 million, $2.2 million in 2018 and $3.8 million in 2017. The Company has undertaken like-kind exchange ("LKE") transactions under the Federal tax code in an effort to acquire and sell real and personal property in a tax efficient manner. The Company generally enters into forward transactions, in which property is sold and the proceeds are reinvested by acquiring similar property; and reverse transactions, in which property is acquired and similar property is subsequently sold. A qualified LKE intermediary is used to facilitate these LKE transactions. Proceeds from forward LKE transactions are held by the intermediary and are classified as restricted cash on the Company's balance sheet because the funds must be reinvested in similar properties. If the acquisition of suitable LKE properties is not completed within 180 days of the sale of the Company-owned property, the proceeds are distributed to the Company by the intermediary and are reclassified as available cash and applicable income taxes are determined. An exchange accommodation titleholder, a type of variable interest entity, is used to facilitate reverse like-kind exchanges. The acquired assets are held by the exchange accommodation titleholder until the exchange transactions are complete. If the Company determines that it is the primary beneficiary of the exchange accommodation titleholder, the replacements assets held by the exchange accommodation titleholder are consolidated and recorded in Property, Plant and Equipment on the Consolidated Balance Sheets. The unspent proceeds that are held in trust with the intermediary are recorded as noncurrent assets in the Consolidated Balance Sheet as the cash was restricted for the acquisition of property, plant and equipment. At December 31, 2019 and December 31, 2018, the Company had no open LKE transactions with an intermediary. IMPAIRMENT OF ASSETS – Long-lived assets, which include property and equipment and finite-lived intangible assets, are tested for recoverability whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. A long-lived asset is not recoverable if its carrying amount exceeds the sum of the undiscounted cash flows expected to result from its use and eventual disposition. If a long-lived asset is not recoverable, an impairment loss is recognized for the amount by which the carrying amount of the long-lived asset exceeds its fair value, with fair value determined based on discounted estimated net cash flows or other appropriate methods. ASSET RETIREMENT OBLIGATIONS – The Company records a liability for asset retirement obligations (“ARO”) equal to the fair value of the estimated cost to retire an asset. The ARO liability is initially recorded in the period in which the obligation meets the definition of a liability, which is generally when the asset is placed in service. The ARO liability is estimated using existing regulatory requirements and anticipated future inflation rates. When the liability is initially recorded, the Company increases the carrying amount of the related long-lived asset by an amount equal to the original liability. The liability is increased over time to reflect the change in its present value, and the capitalized cost is depreciated over the useful life of the related long-lived asset. The Company reevaluates the adequacy of its recorded ARO liability at least annually. Actual costs of asset retirements such as dismantling service stations and site restoration are charged against the related liability. Any difference between costs incurred upon settlement of an asset retirement obligation and the recorded liability is recognized as a gain or loss in the Company’s Consolidated Income Statements. ENVIRONMENTAL LIABILITIES – A liability for environmental matters is established when it is probable that an environmental obligation exists and the cost can be reasonably estimated. If there is a range of reasonably estimated costs, the most likely amount will be recorded, or if no amount is most likely, the minimum of the range is used. Related expenditures are charged against the liability. Environmental remediation liabilities have not been discounted for the time value of future expected payments. Environmental expenditures that have future economic benefit are capitalized. INCOME TAXES – The Company accounts for income taxes using the asset and liability method. Under this method, income taxes are provided for amounts currently payable and for amounts deferred as tax assets and liabilities based on differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities. Deferred income taxes are measured using the enacted tax rates that are assumed will be in effect when the differences reverse. The Company routinely assesses the realizability of deferred tax assets based on available positive and negative evidence including assumptions of future taxable income, tax planning strategies and other pertinent factors. A deferred tax asset valuation allowance is recorded when evidence indicates that it is more likely than not that all or a portion of these deferred tax assets will not be realized in a future period. The accounting principles for income tax uncertainties permit recognition of income tax benefits only when they are more likely than not to be realized. The Company has elected to classify any interest expense and penalties related to the underpayment of income taxes in Income tax expense in the Consolidated Income Statements. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES – The fair value of a derivative instrument is recognized as an asset or liability in the Company’s Consolidated Balance Sheets. Upon entering into a derivative contract, the Company may designate the derivative as either a fair value hedge or a cash flow hedge, or decide that the contract is not a hedge, and therefore, recognize changes in the fair value of the contract in earnings. The Company documents the relationship between the derivative instrument designated as a hedge and the hedged items as well as its objective for risk management and strategy for use of the hedging instrument to manage the risk. Derivative instruments designated as fair value or cash flow hedges are linked to specific assets and liabilities or to specific firm commitments or forecasted transactions. The Company assesses at inception and on an ongoing basis whether a derivative instrument accounted for as a hedge is highly effective in offsetting changes in the fair value or cash flows of the hedged item. A derivative that is not a highly effective hedge does not qualify for hedge accounting. The change in the fair value of a qualifying fair value hedge is recorded in earnings along with the gain or loss on the hedged item. The effective portion of the change in the fair value of a qualifying cash flow hedge is recorded in Accumulated other comprehensive income (AOCI) in the consolidated Balance Sheets until the hedged item is recognized currently in earnings. If a derivative instrument no longer qualifies as a cash flow hedge and the underlying forecasted transaction is no longer probable of occurring, hedge accounting is discontinued and the gain or loss recorded in Accumulated other comprehensive income is recognized immediately in earnings. See Note 12 and Note 15 for further information about the Company’s derivatives. STOCK-BASED COMPENSATION – The fair value of awarded stock options, restricted stock, restricted stock units and performance stock units is determined based on a combination of management assumptions for awards issued. The Company uses the Black-Scholes option pricing model for computing the fair value of stock options. The primary assumptions made by management included the expected life of the stock option award and the expected volatility of the Company’s common stock prices. The Company uses both historical data and current information to support its assumptions. Stock option expense is recognized on a straight-line basis over the requisite service period of three years. The Company uses a Monte Carlo valuation model to determine the fair value of performance-based stock units that are based on performance compared against a peer group and the related expense is recognized over the three-year requisite service period. Management estimates the number of all award that will not vest and adjusts its compensation expense accordingly. Differences between estimated and actual vested amounts are accounted for as an adjustment to expense when known. See Note 10 for a discussion of the basis of allocation of such costs. USE OF ESTIMATES – In preparing the financial statements of the Company in conformity with U.S. GAAP, management has made a number of estimates and assumptions related to the reporting of assets, liabilities, revenues, and expenses and the disclosure of contingent assets and liabilities. Actual results may differ from the estimates. On an ongoing basis, we review our estimates based on currently available information. Changes in facts and circumstances may result in revised estimates.

Revenues

12 Months Ended

Dec. 31, 2019

Revenues

Revenue Recognition

The following table disaggregates our revenue by major source for the years ended December 31, 2019, 2018, and 2017.



	Years Ended December 31,
(Millions of dollars)	2019		2018		2017
Marketing Segment
Petroleum product sales (at retail) ¹	$	10,184.0	$	10,459.2	$	9,041.5
Petroleum product sales (at wholesale) ¹	1,189.8		1,399.2		1,246.4
Total petroleum product sales	11,373.8		11,858.4		10,287.9
Merchandise sales	2,620.1		2,423.0		2,372.6
Other operating revenues:
RINs	34.8		75.2		160.3
Other revenues ²	5.6		5.7		5.4
Total marketing segment revenues	14,034.3		14,362.3		$	12,826.2
Corporate and Other Assets	0.3		0.6		$	0.4
Total revenues	$	14,034.6	$	14,362.9	$	12,826.6

¹ Includes excise and sales taxes that remain eligible for inclusion under Topic 606

² Primarily includes collection allowance on excise and sales taxes and other miscellaneous items

The Company adopted ASC Topic 606, "Revenue from Contracts with Customers" as of January 1, 2018 using the modified retrospective method applied to those contracts which were not completed as of January 1, 2018. Results for reporting periods beginning after January 1, 2018 are presented under Topic 606, while prior period amounts are not adjusted and continue to be reported in accordance with our historical accounting policies under Topic 605. The impact of the excise and sales taxes collected and remitted to government authorities included in petroleum product sales that would have been recognized under previous revenue recognition guidance would have increased petroleum product sales (at retail) by $26.3 million in 2019 and $25.4 million in 2018, petroleum product sales (at wholesale) by $165.6 million in 2019 and $171.2 million in 2018, for a total increase in petroleum product sales of $191.9 million and $196.5 million in 2019 and 2018, respectively.

Marketing segment

Petroleum product sales (at retail). For our retail store locations, the revenue related to petroleum product sales is recognized as the fuel is pumped to our customers. The transaction price at the pump typically includes some portion of sales or excise taxes as levied in the respective jurisdictions. Those taxes that are collected for remittance to governmental entities on a pass through basis are not recognized as revenue and they are recorded to a liability account until they are paid. Our customers typically use a mixture of cash, checks, credit cards and debit cards to pay for our products as they are received. We have accounts receivable from the various credit/debit card providers at any point in time related to product sales made on credit cards and debit cards. These receivables are typically collected in two to seven days, depending on the terms with the particular credit/debit card providers. Payment fees retained by the credit/debit card providers are recorded as station and other operating expenses.

Petroleum product sales (at wholesale). Our sales of petroleum products at wholesale are generally recorded as revenue when the deliveries have occurred and legal ownership of the product has transferred to the customer. Title transfer for bulk refined product sales typically occurs at pipeline custody points and upon trucks loading at product terminals. For bulk pipeline sales, we record receivables from customers that are generally collected within a week from custody transfer date. For our rack product sales, the majority of our customers' accounts are drafted by us within 10 days from product transfer.

Merchandise sales. For our retail store locations, the revenue related to merchandise sales is recognized as the customer completes their purchase at our locations. The transaction price typically includes some portion of sales

tax as levied in the respective jurisdictions. Those taxes that are collected for remittance to governmental entities on a pass through basis are not recognized as revenue and they are recorded to a liability account until they are paid. As noted above, a mixture of payment types are used for these revenues and the same terms for credit/debit card receivables are realized.

The most significant judgment with respect to merchandise sales revenue is determining whether we are the principal or agent for some categories of merchandise such as lottery tickets, lotto tickets, newspapers and other small categories of merchandise. For scratch-off lottery tickets, we have determined we are the principal in the majority of the jurisdictions and therefore we record those sales on a gross basis. We have some categories of merchandise (such as lotto tickets) where we are the agent and the revenues recorded for those transactions are our net commission only.

In June 2018 the Company initiated a loyalty pilot program through a limited number of its retail locations and was rolled out chain-wide in March 2019. The customers earn rewards based on their spending or other promotional activities. This program creates a performance obligation which requires us to defer a portion of sales revenue to the loyalty program participants until they redeem their rewards. The rewards may be redeemed for free or discounted merchandise or cash discounts on fuel purchases. Earned rewards expire after an account is inactive for a period of 90 days. We recognize loyalty revenue when a customer redeems an earned reward. Deferred revenue associated with Murphy Rewards is included in Trade accounts payable and accrued liabilities in our Consolidated Balance Sheet. The deferred revenues recorded in 2019 and 2018 were immaterial.

RINs sales. For the sale of RINs, we recognize revenue when the RIN is transferred to the counter-party and the sale is completed. Receivables from our counter-parties related to the RIN sales are typically collected within five days of the sale.

Other revenues. Items reported as other operating revenues include collection allowances for excise and sales tax and other miscellaneous items and are recognized as revenue when the transaction is completed.

Accounts receivable

Trade accounts receivable on the balance sheet represents both receivables related to contracts with customers and other trade receivables. At December 31, 2019 and December 31, 2018, we had $96.0 million and $79.4 million of receivables, respectively, related to contracts with customers recorded. All of the trade accounts receivable related to contracts with customers outstanding at the end of each period were collected during the succeeding quarter. These receivables were generally related to credit and debit card transactions along with short term bulk and wholesale sales from our customers, which have a very short settlement window.

Inventories

12 Months Ended

Dec. 31, 2019

Inventory Disclosure [Abstract]

Inventories

Inventories consisted of the following:



	December 31,
(Millions of dollars)	2019			2018
Finished products - FIFO basis	$	259.2		$	219.4
Less LIFO reserve - finished products	(160.8		)	(115.5		)
Finished products - LIFO basis	98.4			103.9
Store merchandise for resale	123.0			107.2
Materials and supplies	6.2			10.4
Total inventories	$	227.6		$	221.5

At December 31, 2019 and 2018, the replacement cost (market value) of last-in, first-out (LIFO) inventories exceeded the LIFO carrying value by $160.8 million and $115.5 million, respectively.

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2019

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment



		December 31, 2019				December 31, 2018
(Millions of dollars)	Estimated Useful Life	Cost		Net		Cost		Net
Land		$	598.6	$	598.6	$	591.9	$	591.9
Pipeline and terminal facilities	16 to 25 years	77.5		43.7		73.1		41.6
Retail gasoline stations	3 to 50 years	2,034.4		1,073.6		1,890.6		1,018.5
Buildings	20 to 45 years	60.5		44.9		55.0		41.8
Other	3 to 20 years	115.5		46.5		111.8		54.4
		$	2,886.5	$	1,807.3	$	2,722.4	$	1,748.2

Depreciation expense of $151.2 million, $132.5 million and $115.0 million was recorded for the years ended December 31, 2019, 2018 and 2017, respectively.

Accounts Payable and Accrued Liabilities

12 Months Ended

Dec. 31, 2019

Payables and Accruals [Abstract]

Accounts Payable and Accrued Liabilities

Trade accounts payable and accrued liabilities consisted of the following:



	December 31,
(Millions of dollars)	2019		2018
Trade accounts payable	$	280.8	$	274.9
Excise taxes/withholdings payable	86.2		89.7
Accrued insurance obligations	24.4		21.8
Accrued taxes other than income	25.6		26.6
Other	49.2		43.9
Accounts payable and accrued liabilities	$	466.2	$	456.9

Long-Term Debt

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Long-Term Debt

Long-term debt consisted of the following:



	December 31,
(Millions of dollars)	2019			2018
6.00% senior notes due 2023 (net of unamortized discount of $4.1 at 2018)	$	—		$	495.9
5.625% senior notes due 2027 (net of unamortized discount of $2.7 at 2019 and $3.1 at 2018)	297.3			296.9
4.75 % senior notes due 2029 (net of unamortized discount of $6.1 at 2019)	493.9			—
Term loan due 2020 (effective interest rate of 5.0% at 2018 )	—			72.0
Term loan due 2023 (effective interest rate of 4.3% at 2019)	250.0			—
Capitalized lease obligations, vehicles, due through 2022	2.4			2.3
Unamortized debt issuance costs	(5.5		)	(3.8		)
Total long-term debt	1,038.1			863.3
Less current maturities	38.8			21.2
Total long-term debt, net of current	$	999.3		$	842.1

Senior Notes

On April 25, 2017, Murphy Oil USA, Inc., our primary operating subsidiary, issued $300 million of 5.625% Senior Notes due 2027 (the "2027 Senior Notes") under its existing shelf registration statement. The 2027 Senior Notes

are fully and unconditionally guaranteed by Murphy USA, and are guaranteed by certain 100% owned subsidiaries that guarantee our credit facilities. The indenture governing the 2027 Senior Notes contains restrictive covenants that limit, among other things, the ability of Murphy USA, Murphy Oil USA, Inc. and the restricted subsidiaries to incur additional indebtedness or liens, dispose of assets, make certain restricted payments or investments, enter into transactions with affiliates or merge with or into other entities.

On September 13, 2019, Murphy Oil USA, Inc., consummated a partial tender offer on its 6.00% $500 million Senior Notes due 2023 (the “2023 Senior Notes”). Following the completion of the tender offer, Murphy Oil USA, Inc. called the remaining 2023 Senior Notes and satisfied and discharged the indenture governing the 2023 Senior Notes. We paid a total of $514.5 million which included a call premium and all applicable accrued and unpaid interest. The call premium and unamortized debt discount and issuance costs were reported as Loss on early debt extinguishment in the consolidated income statements for the period ended September 30, 2019.

On September 13, 2019, Murphy Oil USA, Inc., issued $500 million of 4.75% Senior Notes due 2029 (the “2029 Senior Notes”). The net proceeds from the issuance of the 2029 Senior Notes were used to fund, in part, the tender offer and redemption of the 2023 Senior Notes. The 2029 Senior Notes are fully and unconditionally guaranteed by Murphy USA, and are guaranteed by certain 100% owned subsidiaries that guarantee our credit facilities. The indenture governing the 2029 Senior Notes contains restrictive covenants that are essentially identical to the covenants for the 2027 Senior Notes.

The 2027 and 2029 Senior Notes and the guarantees rank equally with all of our and the guarantors’ existing and future senior unsecured indebtedness and effectively junior to our and the guarantors’ existing and future secured indebtedness (including indebtedness with respect to the credit facilities) to the extent of the value of the assets securing such indebtedness. The 2027 and 2029 Senior Notes are structurally subordinated to all of the existing and future third-party liabilities, including trade payables, of our existing and future subsidiaries that do not guarantee the notes.

Credit Facilities and Term Loan

In August 2019, we amended and extended our existing credit agreement. The effective date of the agreement was extended to August, 2024. The credit agreement provides for a committed $325 million asset-based loan (ABL) facility (with availability subject to the borrowing base described below) and a $200 million term loan facility with an additional $50 million available until December 31, 2019. It also provides for a $150 million uncommitted incremental facility. On August 27, 2019, Murphy Oil USA, Inc. borrowed $200 million under the term loan facility that has a four-year term and prepaid the remaining balance of the prior term loan of $57 million. On December 31, 2019, we borrowed the additional $50 million term loan, and at December 31, 2019 had an outstanding balance of $250 million. The term loan is due August 2023 and requires quarterly principal payments of $12.5 million beginning April 1, 2020. As of December 31, 2019, we had zero outstanding under our ABL facility.

The borrowing base is expected, at any time of determination, to be an amount (net of reserves) equal to the sum of:


•	100% of eligible cash at such time, plus


•	90% of eligible credit card receivables at such time, plus


•	90% of eligible investment grade accounts, plus


•	85% of eligible other accounts, plus


•	80% of eligible product supply/wholesale refined products inventory at such time, plus


•	75% of eligible retail refined products inventory at such time, plus

the lesser of (i) 70% of the average cost of eligible retail merchandise inventory at such time and (ii) 85% of the net orderly liquidation value of eligible retail merchandise inventory at such time.

The ABL facility includes a $100 million sublimit for the issuance of letters of credit. Letters of credit issued under the ABL facility reduce availability under the ABL facility.

Interest payable on the credit facilities is based on either:


•	the London interbank offered rate, adjusted for statutory reserve requirements (the “Adjusted LIBO Rate”); or


•	the Alternate Base Rate, which is defined as the highest of (a) the prime rate, (b) the federal funds effective rate from time to time plus 0.50% per annum and (c) the one-month Adjusted LIBO Rate plus 1.00% per annum,

plus, (A) in the case Adjusted LIBO Rate borrowings, (i) with respect to the ABL facility, spreads ranging from 1.50% to 2.00% per annum depending on a total debt to EBITDA ratio under the ABL facility or (ii) with respect to the term facility, spreads ranging from 2.50% to 2.75% per annum depending on a total debt to EBITDA ratio and (B) in the case of Alternate Base Rate borrowings, (i) with respect to the ABL facility, spreads ranging from 0.50% to 1.00% per annum depending on a total debt to EBITDA ratio under the ABL facility or (ii) with respect to the term facility, spreads ranging from 1.50% to 1.75% per annum depending on a total debt to EBITDA ratio.

The interest rate period with respect to the Adjusted LIBO Rate interest rate option can be set at one-, two-, three-, or six-months as selected by us in accordance with the terms of the credit agreement.

The credit agreement contains certain covenants that limit, among other things, the ability of us and our subsidiaries to incur additional indebtedness or liens, to make certain investments, to enter into sale-leaseback transactions, to make certain restricted payments, to enter into consolidations, mergers or sales of material assets and other fundamental changes, to transact with affiliates, to enter into agreements restricting the ability of subsidiaries to incur liens or pay dividends, or to make certain accounting changes. In addition, the credit agreement requires us to maintain a minimum fixed charge coverage ratio of a minimum of 1.0 to 1.0 when availability for at least three consecutive business days is less than the greater of (a) 17.5% of the lesser of the aggregate ABL facility commitments and the borrowing base and (b) $70,000,000 (including as of the most recent fiscal quarter end on the first date when availability is less than such amount) as well as a maximum secured debt to EBITDA ratio of 4.5 to 1.0 at any time when term facility commitments or term loans thereunder are outstanding. As of December 31, 2019, our fixed charge coverage ratio was 0.93 however, we had more than $100 million of availability under the ABL facility at that date so the fixed charge coverage rate currently has no impact on our operations or liquidity. Our secured debt to EBITDA ratio as of December 31, 2019 was 0.58 to 1.0.

The credit agreement contains restrictions on certain payments, including dividends, when availability under the credit agreement is less than or equal to the greater of $100 million and 25% of the lesser of the revolving commitments and the borrowing base and our fixed charge coverage ratio is less than 1.0 to 1.0 (unless availability under the credit agreement is greater than $100 million and 40% of the lesser of the revolving commitments and the borrowing base). As of December 31, 2019, our ability to make restricted payments was not limited as our availability under the borrowing base was more than $100 million, while our fixed charge coverage ratio under our credit agreement was less than 1.0 to 1.0. As of December 31, 2019, the Company had a shortfall of approximately $30.6 million of our net income and retained earnings subject to such restrictions before the fixed charge coverage ratio would exceed 1.0 to 1.0.

All obligations under the credit agreement are guaranteed by Murphy USA and the subsidiary guarantors party thereto, and all obligations under the credit agreement, including the guarantees of those obligations, are secured by certain assets of Murphy USA, Murphy Oil USA, Inc. and the guarantors party thereto.

Asset Retirement Obligations (ARO)

12 Months Ended

Dec. 31, 2019

Asset Retirement Obligation Disclosure [Abstract]

Asset Retirement Obligations (ARO)

The majority of the ARO recognized by the Company at December 31, 2019 and 2018 related to the estimated costs to dismantle and abandon certain of its retail gasoline stations. The Company has not recorded an ARO for certain of its marketing assets because sufficient information is presently not available to estimate a range of potential settlement dates for the obligation. These assets are consistently being upgraded and are expected to be operational into the foreseeable future. In these cases, the obligation will be initially recognized in the period in which sufficient information exists to estimate the obligation.

A reconciliation of the beginning and ending aggregate carrying amount of the ARO is shown in the following table.



	December 31,
(Millions of dollars)	2019			2018
Balance at beginning of period	$	30.7		$	28.2
Accretion expense	2.1			2.0
Settlement of liabilities	(0.4		)	(0.3		)
Liabilities incurred	0.4			0.8
Balance at end of period	$	32.8		$	30.7

The estimation of future ARO is based on a number of assumptions requiring professional judgment. The Company cannot predict the type of revisions to these assumptions that may be required in future periods due to the lack of availability of additional information.

Income Taxes

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Income Taxes

The components of income before income taxes for each of the three years ended December 31, 2019 and income tax expense (benefit) attributable thereto were as follows:



	Years Ended December 31,
(Millions of dollars)	2019		2018		2017
Income (loss) before income taxes	$	202.4	$	273.9	$	240.1
Income tax expense (benefit)
Federal - Current	$	15.6	18.4		39.2
Federal - Deferred	21.7		31.0		(50.7		)
State - Current and deferred	10.3		10.9		6.3
Total	$	47.6	$	60.3	$	(5.2	)

The following table reconciles income taxes based on the U.S. statutory tax rate to the Company’s income tax expense (benefit).



	Years Ended December 31,
(Millions of dollars)	2019			2018			2017
Income tax expense based on the U.S. statutory tax rate	$	42.5		$	57.5		$	84.0
State income taxes, net of federal benefit	8.6			8.3			3.0
Effect of U.S. tax law change	—			—			(88.9		)
Federal credits	(2.3		)	(2.0		)	(1.0		)
Other, net	(1.2		)	(3.5		)	(2.3		)
Total	$	47.6		$	60.3		$	(5.2	)

An analysis of the Company’s deferred tax assets and deferred tax liabilities at December 31, 2019 and 2018 showing the tax effects of significant temporary differences is as follows:



	December 31,
(Millions of dollars)	2019			2018
Deferred tax assets
Property costs and asset retirement obligations	$	3.7		$	3.3
Employee benefits	6.1			6.3
Operating leases liability	25.0			—
Other deferred tax assets	2.1			2.6
Total gross deferred tax assets	36.9			12.2
Deferred tax liabilities
Accumulated depreciation and amortization	(191.2		)	(171.6		)
State deferred taxes	(27.9		)	(25.9		)
Operating leases right of use assets	(24.8		)	—
Other deferred tax liabilities	(9.7		)	(6.9		)
Total gross deferred tax liabilities	(253.6		)	(204.4		)
Net deferred tax liabilities	$	(216.7	)	$	(192.2	)

In management’s judgment, the net deferred tax assets in the preceding table will more likely than not be realized as reductions of future taxable income or by utilizing available tax planning strategies.

In December 2017, the Tax Cuts and Jobs Act ("the Act") was enacted, which made major changes to the Federal income tax system for corporations and individuals. Two key corporate provisions of the Act that impacted the Company in 2017 were the reduction of the Federal corporate income tax rate from 35% to 21% and the increase of Federal bonus depreciation from 50% to 100% on certain qualifying assets retroactive to September 27, 2017. As a result, the Company calculated the impact of the Act in its year-end income tax provision in accordance with its understanding of the Act and guidance available as of the date of the filing and as a result recorded $88.9 million as a tax benefit in the fourth quarter of 2017, the period in which the legislation was enacted. The provisional amount related primarily to the remeasurement of certain deferred tax assets and liabilities based on the rates of which they are expected to reverse in the future.

In conjunction with the effectiveness of the Act, the SEC issued Staff Accounting Bulletin No. 118 ("SAB 118") to address the implications of U.S. GAAP in situations where the registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Act. In accordance with SAB 118, the Company made its best estimate and recorded provisional amounts related to certain equity and fixed asset temporary differences based on available information as of December 31, 2017. These amounts were finalized in the fourth quarter of 2018 and with immaterial adjustments being recorded as a component of tax expense.

As of December 31, 2019, the earliest year remaining open for Federal audit and/or settlement is 2016 and for the states it ranges from 2014-2018. Although the Company believes that recorded liabilities for unsettled issues are adequate, additional gains or losses could occur in future periods from resolution of outstanding unsettled matters.

The FASB’s rules for accounting for income tax uncertainties clarify the criteria for recognizing uncertain income tax benefits and require additional disclosures about uncertain tax positions. Under U.S. GAAP the financial statement recognition of the benefit for a tax position is dependent upon the benefit being more likely than not to be sustainable upon audit by the applicable taxing authority. If this threshold is met, the tax benefit is then measured and recognized at the largest amount that is greater than 50 percent likely of being realized upon ultimate settlement. Liabilities associated with uncertain income tax positions are included in Deferred Credits and Other Liabilities in the Consolidated Balance Sheets.

A reconciliation of the beginning and ending amount of the consolidated liability for unrecognized income tax benefits during the year ended December 31, 2019 and 2018 is shown in the following table.



	Year Ended December 31,
(Millions of dollars)	2019			2018
Balance at January 1	$	0.7		$	4.4
Additions for tax positions related to prior years	0.5			—
Additions for tax positions related to current year	—			0.2
Settlements with taxing authorities	(0.6		)	(3.9		)
Expiration of statutes of limitation	—			—
Balance at December 31	$	0.6		$	0.7

All additions or reductions to the above liability affect the Company’s effective tax rate in the respective period of change. The Company accounts for any applicable interest and penalties on uncertain tax positions as a component of income tax expense. Income tax expense for the years ended December 31, 2019, 2018 and 2017 included interest and penalties of none, $(1.6) million, and $0.4 million, respectively, associated with uncertain tax positions.

During the next twelve months, the Company currently expects to add immaterial amounts to the liability for uncertain taxes for 2020 events. Although existing liabilities could be reduced by settlement with taxing authorities or lapse due to statute of limitations, the Company believes that the changes in its unrecognized tax benefits due to these events will not have a material impact on the Consolidated Income Statement during 2020.

Total excess tax benefits recognized in the twelve months ended December 31, 2019, 2018 and 2017 were $0.1 million, $2.5 million, and $2.2 million respectively.

Incentive Plans

12 Months Ended

Dec. 31, 2019

Share-based Payment Arrangement [Abstract]

Incentive Plans

2013 Long-Term Incentive Plan

Effective August 30, 2013, certain of our employees began to participate in the Murphy USA 2013 Long-Term Incentive Plan, which was subsequently amended and restated effective as of February 8, 2017 (the “MUSA 2013 Plan”). The MUSA 2013 Plan authorizes the Executive Compensation Committee of our Board of Directors (“the Committee”) to grant non-qualified or incentive stock options, stock appreciation rights, stock awards (including restricted stock and restricted stock unit awards), cash awards, and performance awards to our employees. No more than 5.5 million shares of common stock may be delivered under the MUSA 2013 Plan and no more than 1 million shares of common stock may be awarded to any one employee, subject to adjustment for changes in capitalization. The maximum cash amount payable pursuant to any “performance-based” award to any participant in any calendar year is $5.0 million.

During the period from August 30, 2013 to December 31, 2019, the Company granted a total of 2,339,812 awards from the MUSA 2013 Plan which leaves 3,160,188 remaining shares to be granted in future years (after consideration of the amendments made to the MUSA 2013 Plan in February 2014 by the Board of Directors). At present, the Company expects to issue all shares that vest out of existing treasury shares rather than issuing new common shares.

2013 Stock Plan for Non-employee Directors

Effective August 8, 2013, Murphy USA adopted the 2013 Murphy USA Stock Plan for Non-employee Directors (the “Directors Plan”). The directors for Murphy USA are compensated with a mixture of cash payments and equity-based awards. Awards under the Directors Plan may be in the form of restricted stock, restricted stock units, stock options, or a combination thereof. An aggregate of 500,000 shares of common stock shall be available for issuance of grants under the Directors Plan. Since 2013, 123,629 time-based restricted stock units have been granted under the terms of the Directors Plan which leaves 376,371 shares available to be granted in the future.

Amounts recognized in the financial statements by the Company with respect to all share-based plans are shown in the following table.



	Years Ended December 31,
(Millions of dollars)	2019		2018		2017
Compensation charged against income before income tax benefit	$	10.5	$	9.2	$	7.5
Related income tax benefit recognized in income	$	2.2	$	1.9	$	2.6

As of December 31, 2019, there was $14.1 million in compensation costs to be expensed over approximately the next 1.8 years related to unvested share-based compensation arrangements granted by the Company. Employees who have stock options are required to net settle their options in shares, after applicable statutory withholding taxes are considered, upon each stock option exercise. Therefore, no cash is received upon exercise. Total income tax benefits realized from tax deductions related to stock option exercises under share-based payment arrangements were $0.1 million, $2.1 million, and $0.6 million for the years ended December 31, 2019, 2018, and 2017, respectively.

STOCK OPTIONS – The Committee fixes the option price of each option granted at no less than fair market value (FMV) on the date of the grant and fixes the option term at no more than 7 years from such date.

In February 2019, the Committee granted nonqualified stock options to certain employees of the Company.

Following are the assumptions used by the Company to value the original awards:



	Years Ended December 31,
	2019			2018			2017
Fair value per option grant	$	20.48		$	17.32		$	15.45
Assumptions
Dividend yield	—			—			—
Expected volatility	26.8		%	27.0		%	26		%
Risk-free interest rate	2.5		%	2.43		%	1.65		%
Expected life (years)	4.5			3.9			4.2
Stock price at valuation date	$	76.15		$	71.00		$	65.75

Changes in options outstanding for Company employees during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Options	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (Millions of Dollars)
Outstanding at December 31, 2018	310,362		65.71
Granted	99,400		76.15
Exercised	(12,662	)	56.63
Forfeited	(4,800	)	76.15
Outstanding at December 31, 2019	392,300		$	68.52	4.3	$	19.0

Exercisable at December 31, 2019	174,300		$	64.00	3.0	$	9.2

Additional information about stock options outstanding at December 31, 2019 is shown below:



	Options Outstanding		Options Exercisable
Range of Exercise Prices per Option	No. of Options	Avg. Life Remaining in Years	No. of Options	Avg. Life Remaining in Years
$39.46 to $49.99	3,900	1.1	3,900	1.1
$50.00 to $59.99	71,000	3.1	71,000	3.1
$60.00 to $69.99	90,550	4.1	43,550	4.1
$70.00 to $79.99	226,850	4.8	55,850	2.1
	392,300	4.3	174,300	3.0

RESTRICTED STOCK UNITS (MUSA 2013 Plan) – The Committee has granted time based restricted stock units (RSUs) as part of the compensation plan for its executives and certain other employees since its inception. The awards granted in the current year were under the MUSA 2013 Plan, are valued at the grant date fair value, and vest over 3 years.

Changes in restricted stock units outstanding for Company employees during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Employee RSUs	Number of units		Weighted Average Grant Date Fair Value		Total Fair Value (Millions of Dollars)
Outstanding at December 31, 2018	193,478		$	64.02
Granted	74,118		$	80.85
Vested and issued	(54,313	)	$	60.41	$	4.2
Forfeited	(14,368	)	$	73.63
Outstanding at December 31, 2019	198,915		$	70.58	$	23.3

PERFORMANCE-BASED RESTRICTED STOCK UNITS (MUSA 2013 Plan) – In February 2019, the Committee awarded performance-based restricted stock units (performance units) to certain employees. Half of the performance units vest based on a 3-year return on average capital employed (ROACE) calculation and the other half vest based on a 3-year total shareholder return (TSR) calculation that compares MUSA to a group of 19 peer companies. The portion of the awards that vest based on TSR qualify as a market condition and must be valued using a Monte Carlo valuation model. For the TSR portion of the awards, the fair value was determined to be $100.65 per unit. For the ROACE portion of the awards, the valuation was based on the grant date fair value of $76.15 per unit and the number of awards will be periodically assessed to determine the probability of vesting.

Changes in performance-based restricted stock units outstanding for Company employees during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Employee PSU's	Number of Units		Weighted Average Grant Date Fair Value		Total Fair Value (Millions of Dollars)
Outstanding at December 31, 2018	124,412		$	76.58
Granted	81,513		$	88.40
Vested and issued	(72,125	)	$	73.55	$	5.5
Forfeited	(2,600	)	$	88.40
Outstanding at December 31, 2019	131,200		$	82.98	$	15.4

RESTRICTED STOCK UNITS (Directors Plan) – The Committee has also granted time based RSUs to the non-employee directors of the Company as part of their overall compensation package for being a member of the Board of Directors. These awards typically vest at the end of three years.

Changes in restricted stock units outstanding for Company non-employee directors during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Director RSU's	Number of Units		Weighted Average Grant Date Fair Value		Total Fair Value (Millions of Dollars)
Outstanding at December 31, 2018	41,017		$	64.27
Granted	13,086		$	76.63
Vested and issued	(20,496	)	$	61.65	$	1.6
Forfeited	—
Outstanding at December 31, 2019	33,607		$	70.68	$	3.9

Employee and Retiree Benefit Plans	12 Months Ended
Employee and Retiree Benefit Plans	Dec. 31, 2019
Retirement Benefits [Abstract]
Employee and Retiree Benefit Plans	Employee and Retiree Benefit Plans THRIFT PLAN – Most full-time employees of the Company may participate in defined contribution savings plans by contributing up to a specified percentage of their base pay. The Company matches contributions at 100% of each employee’s contribution with a maximum match of 6%. In addition, the Company makes profit sharing contributions on an annual basis. Eligible employees receive a stated percentage of their base and incentive pay of 5%, 7%, or 9% determined on a formula that is based on a combination of age and years of service. The Company’s combined expenses related for this plan were $12.9 million in 2019, $9.7 million in 2018 and $12.1 million in 2017. PROFIT SHARING PLAN – Eligible part-time employees may participate in the Company’s noncontributory profit sharing plan. Each year, the Company may make a discretionary employer contribution in an amount determined and authorized at the discretion of the Board of Directors. Eligible employees receive an allocation based on their compensation earned for the year the contribution is allocated. The Company’s expenses related to this plan were $1.5 million in 2019, $(0.8) million in 2018 and $2.2 million in 2017.

Financial Instruments and Risk Management	12 Months Ended
Financial Instruments and Risk Management	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments and Risk Management	Financial Instruments and Risk Management DERIVATIVE INSTRUMENTS — The Company makes limited use of derivative instruments to manage certain risks related to commodity prices and interest rates. The use of derivative instruments for risk management is covered by operating policies and is closely monitored by the Company’s senior management. The Company does not hold any derivatives for speculative purposes and it does not use derivatives with leveraged or complex features. Derivative instruments are traded primarily with creditworthy major financial institutions or over national exchanges such as the New York Mercantile Exchange (“NYMEX”). For accounting purposes, the company has not designated commodity derivative contracts as hedges, and therefore, it recognizes all gains and losses on these derivative contracts in its Consolidated Statement of Income. Certain interest rate derivative contracts were accounted for as hedges and gain or loss associated with recording the fair value of these contracts was deferred in AOCI until the anticipated transactions occur. As of December 31, 2019, all current commodity derivative activity is immaterial. At December 31, 2019 and 2018 cash deposits of $1.0 million related to commodity derivative contracts were reported in Prepaid expenses and other current assets in the Consolidated Balance Sheets. These cash deposits have not been used to reduce the reported net liabilities on the derivative contracts at December 31, 2019 and 2018. Interest Rate Risks Under hedge accounting rules, the Company deferred the net benefit associated with the interest rate swap entered into to manage the variability in interest payments for the variable-rate debt in association with $150 million of our outstanding term loan dated August 27, 2019. The effective date of the hedge was September 27, 2019, and under the swap the Company pays fixed rate interest and receives one month LIBOR to hedge the floating interest rate of the outstanding debt. During the year ended December 31, 2019, $0.2 million of realized gain on the interest rate swaps was credited to interest expense in the Consolidated Statements of Income. The remaining benefit pre-tax deferred on these contracts at December 31, 2019 was $0.9 million, which is recorded, net of income taxes, of $0.2 million, in AOCI in the Consolidated Balance Sheets.

Earnings Per Share

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Earnings Per Share

Basic earnings per common share is computed by dividing net income available to common stockholders by the weighted average of common shares outstanding during the period. Diluted earnings per common share adjusts basic earnings per common share for the effects of stock options and restricted stock in the periods where such items are dilutive.

On August 30, 2013, 46,743,316 shares of our common stock were distributed to the shareholders of Murphy Oil in connection with the separation. For comparative purposes, we have assumed this amount to be outstanding as of the beginning of each prior period prior to the separation presented in the calculation of weighted average shares outstanding.

On July 24, 2019, the Board of Directors approved an up to $400 million share repurchase program to be executed over the two-year period ending July 2021. Prior to the July authorization, the Company had continued to conduct repurchases under quarterly allocations in line with recent past practice. During 2019, total purchases were made of 1,898,023 common shares for $165.8 million,or $87.35 per share, of which 1,393,626 common shares for $125.0 million were made under the July 2019 authorization, leaving approximately $275.0 million available until July 2021. Previous authorizations for common share repurchases include May 2014, in which 1,040,636 common shares were acquired for an average price (including brokerage fees) of $48.07 per share, October 2014, in which 4,169,349 common shares were repurchased for an average price of $59.96 per share, January 2016, in which 7,489,388 common shares for an average price of $66.76 per share, and after completion of the 2016 program, an additional 379,054 common shares at an average price of $77.20 were repurchased in 2017. During 2018 the Company acquired 1,994,632 common shares at an average price of $72.39.

The following table provides a reconciliation of basic and diluted earnings per share computations for the years ended December 31, 2019, 2018 and 2017 (in millions, except per share amounts):



	Years ended December 31,
(Millions of dollars except per share amounts)	2019		2018		2017
Earnings per common share:
Net income per share - basic
Net income attributable to common stockholders	$	154.8	$	213.6	$	245.3

Weighted average common shares outstanding (in thousands)	31,594		32,674		35,816
Earnings per common share	$	4.90	$	6.54	$	6.85

Earnings per common share - assuming dilution:
Net income per share - diluted
Net income attributable to common stockholders	$	154.8	$	213.6	$	245.3
Weighted average common shares outstanding (in thousands)	31,594		32,674		35,816
Common equivalent shares:
Share-based awards	264		309		340
Weighted average common shares outstanding - assuming dilution (in thousands)	31,858		32,983		36,156

Earnings per common share assuming dilution	$	4.86	$	6.48	$	6.78

We have excluded from the earnings-per-share calculation certain stock options and shares that are considered to be anti-dilutive under the treasury stock method. For the reported periods, the number of time-based restrictive stock units, performance based units and non-qualified stock options that are excluded due to their anti-dilutive nature is immaterial.

Other Financial Information

12 Months Ended

Dec. 31, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Other Financial Information

CASH FLOW DISCLOSURES — Cash income taxes paid (collected), net of refunds, were $26.9 million, $17.4 million and $51.7 million for the three years ended December 31, 2019, 2018 and 2017, respectively. Interest paid, net of amounts capitalized, was $56.6 million, $50.4 million and $41.5 million for the years ended December 31, 2019, 2018 and 2017, respectively.

CHANGES IN WORKING CAPITAL -



(Millions of dollars)	2019			2018			2017
Accounts receivable	$	(33.4	)	$	86.6		$	(41.7	)
Inventories	(6.1		)	(39.0		)	(16.3		)
Prepaid expenses and other current assets	(3.3		)	11.4			(5.2		)
Accounts payable and accrued liabilities	(5.9		)	(56.7		)	26.9
Income taxes payable	—			—			(0.6		)
Net decrease (increase) in noncash operating working capital	$	(48.7	)	$	2.3		$	(36.9	)

Assets and Liabilities Measure at Fair Value

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Assets and Liabilities Measure at Fair Value

Assets and Liabilities Measured at Fair Value

The Company carries certain assets and liabilities at fair value in its Consolidated Balance Sheets. The fair value hierarchy is based on the quality of inputs used to measure fair value, with Level 1 being the highest quality and Level 3 being the lowest quality. Level 1 inputs are quoted prices in active markets for identical assets or liabilities. Level 2 inputs are observable inputs other than quoted prices included within Level 1. Level 3 inputs are unobservable inputs which reflect assumptions about pricing by market participants.

At the balance sheet date, the fair value of commodity derivatives contracts was determined using NYMEX quoted values but were immaterial. The carrying value of the Company’s Cash and cash equivalents, Accounts receivable-trade, Trade accounts payable, interest rate swap contracts and accrued liabilities approximates fair value.

The following table presents the carrying amounts and estimated fair values of financial instruments held by the Company at December 31, 2019 and 2018. The fair value of a financial instrument is the amount at which the instrument could be exchanged in a current transaction between willing parties. The table excludes Cash and cash equivalents, Accounts receivable-trade, and Trade accounts payable and accrued liabilities, all of which had fair values approximating carrying amounts. The fair value of Current and Long-term debt was estimated based on rates offered to the Company at that time for debt of the same maturities. The Company has off-balance sheet exposures relating to certain financial guarantees and letters of credit. The fair value of these, which represents fees associated with obtaining the instruments, was nominal.



	December 31, 2019						December 31, 2018
	Carrying						Carrying
(Millions of dollars)	Amount			Fair Value			Amount			Fair Value
Financial liabilities
Current and long-term debt	$	(1,038.1	)	$	(1,069.4	)	$	(863.3	)	$	(866.7	)

Quarterly Financial Information Disclosure [Abstract]

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Commitments	12 Months Ended
Commitments	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments	Commitments The Company leases land, gasoline stations, and other facilities under operating leases. During the next five years, expected future rental payments under all operating leases are approximately $14.9 million in 2020, $14.3 million in 2021, $13.5 million in 2022, $13.0 million in 2023, and $12.2 million in 2024. Rental expense for noncancelable operating leases, including contingent payments when applicable, was $21.6 million in 2019, $15.2 million in 2018 and $14.0 million in 2017. Commitments for capital expenditures were approximately $246.9 million at December 31, 2019, including $202.9 million approved for potential construction of future Murphy USA and Murphy Express gasoline stations (including land) at year-end, along with $39.2 million for improvements of existing stations, to be financed with our operating cash flow and/or incurrence of indebtedness. The Company has certain take-or-pay contracts primarily to supply our terminals with a noncancelable remaining term of 1.7 years. At December 31, 2019, our minimum annual payments under our take-or-pay contracts are estimated to be $7.9 million in 2020 and $4.9 million in 2021.

Contingencies	12 Months Ended
Contingencies	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies The Company’s operations and earnings have been and may be affected by various forms of governmental action. Examples of such governmental action include, but are by no means limited to: tax increases and retroactive tax claims; import and export controls; price controls; allocation of supplies of crude oil and petroleum products and other goods; laws and regulations intended for the promotion of safety and the protection and/or remediation of the environment; governmental support for other forms of energy; and laws and regulations affecting the Company’s relationships with employees, suppliers, customers, stockholders and others. Because governmental actions are often motivated by political considerations, may be taken without full consideration of their consequences, and may be taken in response to actions of other governments, it is not practical to attempt to predict the likelihood of such actions, the form the actions may take or the effect such actions may have on the Company. ENVIRONMENTAL MATTERS AND LEGAL MATTERS — Murphy USA is subject to numerous federal, state and local laws and regulations dealing with the environment. Violation of such environmental laws, regulations and permits can result in the imposition of significant civil and criminal penalties, injunctions and other sanctions. A discharge of hazardous substances into the environment could, to the extent such event is not insured, subject the Company to substantial expense, including both the cost to comply with applicable regulations and claims by neighboring landowners and other third parties for any personal injury, property damage and other losses that might result. The Company currently owns or leases, and has in the past owned or leased, properties at which hazardous substances have been or are being handled. Although the Company believes it has used operating and disposal practices that were standard in the industry at the time, hazardous substances may have been disposed of or released on or under the properties owned or leased by the Company or on or under other locations where they have been taken for disposal. In addition, many of these properties have been operated by third parties whose management of hazardous substances was not under the Company’s control. Under existing laws, the Company could be required to remediate contaminated property (including contaminated groundwater) or to perform remedial actions to prevent future contamination. Certain of these contaminated properties are in various stages of negotiation, investigation, and/or cleanup, and the Company is investigating the extent of any related liability and the availability of applicable defenses. With the sale of the U.S. refineries in 2011, Murphy Oil retained certain liabilities related to environmental matters. Murphy Oil also obtained insurance covering certain levels of environmental exposures. With respect to the previously owned refinery properties, Murphy Oil retained those liabilities in the Separation and Distribution agreement that was entered into related to the separation on August 30, 2013. With respect to any remaining potential liabilities, the Company believes costs related to these sites will not have a material adverse effect on Murphy USA’s net income, financial position or liquidity in a future period. Certain environmental expenditures are likely to be recovered by the Company from other sources, primarily environmental funds maintained by certain states. Since no assurance can be given that future recoveries from other sources will occur, the Company has not recorded a benefit for likely recoveries at December 31, 2019, however certain jurisdictions provide reimbursement for these expenses which have been considered in recording the net exposure. The U.S. Environmental Protection Agency (EPA) currently considers the Company a Potentially Responsible Party (PRP) at one Superfund site. As to the site, the potential total cost to all parties to perform necessary remedial work at this site may be substantial. However, based on current negotiations and available information, the Company believes that it is a de minimis party as to ultimate responsibility at the Superfund site. Accordingly, the Company has not recorded a liability for remedial costs at the Superfund site at December 31, 2019. The Company could be required to bear a pro rata share of costs attributable to nonparticipating PRPs or could be assigned additional responsibility for remediation at this site or other Superfund sites. The Company believes that its share of the ultimate costs to clean-up this site will be immaterial and will not have a material adverse effect on its net income, financial position or liquidity in a future period. Based on information currently available to the Company, the amount of future remediation costs to be incurred to address known contamination sites is not expected to have a material adverse effect on the Company’s future net income, cash flows or liquidity. However, there is the possibility that additional environmental expenditures could be required to address contamination, including as a result of discovering additional contamination or the imposition of new or revised requirements applicable to known contamination. Murphy USA is engaged in a number of other legal proceedings, all of which the Company considers routine and incidental to its business. Based on information currently available to the Company, the ultimate resolution of those other legal matters is not expected to have a material adverse effect on the Company’s net income, financial condition or liquidity in a future period. INSURANCE — The Company maintains insurance coverage at levels that are customary and consistent with industry standards for companies of similar size. Murphy USA maintains statutory workers compensation insurance with a deductible of $1.0 million per occurrence, general liability insurance with a deductible of $3.0 million per occurrence, and auto liability insurance with a deductible of $0.3 million per occurrence. As of December 31, 2019, there were a number of outstanding claims that are of a routine nature. The estimated incurred but unpaid liabilities relating to these claims are included in Trade account payables and accrued liabilities on the Consolidated Balance Sheets. While the ultimate outcome of these claims cannot presently be determined, management believes that the accrued liability of $21.8 million will be sufficient to cover the related liability and that the ultimate disposition of these claims will have no material effect on the Company’s financial position and results of operations. The Company has obtained insurance coverage as appropriate for the business in which it is engaged, but may incur losses that are not covered by insurance or reserves, in whole or in part, and such losses could adversely affect our results of operations and financial position. TAX MATTERS — Murphy USA is subject to extensive tax liabilities imposed by multiple jurisdictions, including income taxes, indirect taxes (excise/duty, sales/use and gross receipts taxes), payroll taxes, franchise taxes, withholding taxes and ad valorem taxes. New tax laws and regulations and changes in existing tax laws and regulations are continuously being enacted or proposed that could result in increased expenditures for tax liabilities in the future. Many of these liabilities are subject to periodic audits by the respective taxing authority. Subsequent changes to our tax liabilities because of these audits may subject us to interest and penalties. OTHER MATTERS — In the normal course of its business, the Company is required under certain contracts with various governmental authorities and others to provide financial guarantees or letters of credit that may be drawn upon if the Company fails to perform under those contracts. At December 31, 2019, the Company had contingent liabilities of $17.0 million on outstanding letters of credit. The Company has not accrued a liability in its balance sheet related to these financial guarantees and letters of credit because it is believed that the likelihood of having these drawn is remote.

Lease Accounting

12 Months Ended

Dec. 31, 2019

Leases [Abstract]

Lease Accounting

Leases

In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)" (“ASU 2016-02”). ASU 2016-02 amended the existing accounting standards for lease accounting by recognizing lease assets and lease liabilities on the balance sheet for those leases classified as operating leases under current GAAP. ASU 2016-02 requires that a lessee should recognize a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term on the balance sheet. We adopted ASU 2016-02 as of January 1, 2019, using the modified retrospective approach. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed us to carry forward the historical lease classification. We also elected the practical expedient related to land easements, allowing us to carry forward our accounting treatment for land easements on existing agreements. In addition, we elected the hindsight practical expedient to determine the lease term for existing leases. Our election of the hindsight practical expedient resulted in the shortening of lease terms for certain existing leases and the useful lives of corresponding leasehold improvements. In our application of hindsight, we evaluated the performance of the leased stores and the associated markets in relation to our overall real estate strategies, which resulted in the determination that renewal options would not be reasonably certain in determining the expected lease term. Adoption of the new standard resulted in the recording of additional net lease assets and lease liabilities of approximately $110.4 million and $110.7 million, respectively. The standard did not materially impact our consolidated net earnings and had no impact on cash flows.

The Company determines if an arrangement is a lease or contains a lease at inception. Operating lease right-of-use assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Leases with an initial term of 12 months or less are not recorded on the balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. The Company's leases have remaining lease terms of approximately 1 year to 20 years, which may include the option to extend the lease when it is reasonably certain the Company will exercise the option. Most leases include one or more options to renew, with renewal terms that can extend the lease term from five to 20 years or more. The exercise of lease renewal options is at the Company's sole discretion. Due to the uncertainties of future markets, economic factors, technology changes, demographic shifts and behavior, environmental regulatory requirements and other information that impacts decisions as to station location, management has determined that it was not reasonably certain to exercise contract options and they are not included in the lease term. Additionally, short-term leases and leases with variable lease costs are immaterial. The Company reviews all options to extend, terminate, or otherwise modify its lease agreements to determine if changes are required to the right of use assets and liabilities.

As the implicit interest rate is not readily determinable in most of the Company's lease agreements, the Company uses its estimated secured incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments.

Lessor — We have various arrangements for certain spaces for food service and vending equipment under which we are the lessor. These leases meet the criteria for operating lease classification. Lease income associated with these leases is immaterial.

Lessee —We lease land for 215 stations, one terminal, a hangar and various equipment. Our lease agreements do not contain any material residual value guarantees and approximately 102 sites leased from Walmart contain restrictive covenants, though the restrictions are deemed to have an immaterial impact.

Leases are reflected in the following balance sheet accounts:



(Millions of dollars)	Classification	December 31, 2019		December 31, 2018
Assets
Operating (Right-of-use)	Other Assets	$	124.2	$	—
Finance	Property, plant, and equipment, at cost, less accumulated depreciation of $2.2 in 2019 and$1.8 in 2018	3.0		2.9
Total leased assets		$	127.2	$	2.9

Liabilities
Current
Operating	Trade accounts payable and accrued liabilities	$	6.8	$	—
Finance	Current maturities of long-term debt	1.2		1.2
Noncurrent
Operating	Deferred credits and other liabilities	118.5		—
Finance	Long-term debt, including capitalized lease obligations	1.2		1.1
Total lease liabilities		$	127.7	$	2.3

Lease Cost:



		Year Ended December 31,
(Millions of dollars)	Classification	2019
Operating lease cost	Station and other operating expenses	$	14.5
Finance lease cost
Amortization of leased assets	Depreciation & amortization expense	1.2
Interest on lease liabilities	Interest expense	0.1
Net lease costs		$	15.8

Cash flow information:



	Year Ended December 31,
(Millions of dollars)	2019
Cash paid for amounts included in the measurement of liabilities
Operating cash flows required by operating leases	$	13.8
Operating cash flows required by finance leases	$	0.1
Financing cash flows required by finance leases	$	1.4

Maturity of Lease Liabilities:



(Millions of dollars)	Operating leases		Finance leases
2020	$	14.9	$	1.3
2021	14.3		0.9
2022	13.5		0.3
2023	13.0		—
2024	12.2		—
After 2024	148.9		—
Total lease payments	216.8		2.5
less: interest	91.5		0.1
Present value of lease liabilities	$	125.3	$	2.4

The Company adopted ASU 2016-02 on January 1, 2019, and as required, the following disclosure is provided for periods prior to adoption. Future annual minimum lease payments and capital lease commitments as of December 31, 2018 were as follows:



(Millions of dollars)	Operating leases		Capital leases
2019	$	13.7	$	1.5
2020	13.3		1.1
2021	12.5		0.6
2022	11.7		0.1
2023	11.1		—
After 2023	122.6		—
Total lease payments	184.9		3.3
less: interest	—		0.2
Present value of minimum payments	$	184.9	$	3.1

Lease Term and Discount Rate:



	Year Ended December 31,
	2019
Weighted average remaining lease term (years)
Finance leases	2.0
Operating leases	15.6
Weighted average discount rate
Finance leases	4.8	%
Operating leases	6.0	%

Lease Accounting

Leases

In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)" (“ASU 2016-02”). ASU 2016-02 amended the existing accounting standards for lease accounting by recognizing lease assets and lease liabilities on the balance sheet for those leases classified as operating leases under current GAAP. ASU 2016-02 requires that a lessee should recognize a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term on the balance sheet. We adopted ASU 2016-02 as of January 1, 2019, using the modified retrospective approach. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed us to carry forward the historical lease classification. We also elected the practical expedient related to land easements, allowing us to carry forward our accounting treatment for land easements on existing agreements. In addition, we elected the hindsight practical expedient to determine the lease term for existing leases. Our election of the hindsight practical expedient resulted in the shortening of lease terms for certain existing leases and the useful lives of corresponding leasehold improvements. In our application of hindsight, we evaluated the performance of the leased stores and the associated markets in relation to our overall real estate strategies, which resulted in the determination that renewal options would not be reasonably certain in determining the expected lease term. Adoption of the new standard resulted in the recording of additional net lease assets and lease liabilities of approximately $110.4 million and $110.7 million, respectively. The standard did not materially impact our consolidated net earnings and had no impact on cash flows.

The Company determines if an arrangement is a lease or contains a lease at inception. Operating lease right-of-use assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Leases with an initial term of 12 months or less are not recorded on the balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. The Company's leases have remaining lease terms of approximately 1 year to 20 years, which may include the option to extend the lease when it is reasonably certain the Company will exercise the option. Most leases include one or more options to renew, with renewal terms that can extend the lease term from five to 20 years or more. The exercise of lease renewal options is at the Company's sole discretion. Due to the uncertainties of future markets, economic factors, technology changes, demographic shifts and behavior, environmental regulatory requirements and other information that impacts decisions as to station location, management has determined that it was not reasonably certain to exercise contract options and they are not included in the lease term. Additionally, short-term leases and leases with variable lease costs are immaterial. The Company reviews all options to extend, terminate, or otherwise modify its lease agreements to determine if changes are required to the right of use assets and liabilities.

As the implicit interest rate is not readily determinable in most of the Company's lease agreements, the Company uses its estimated secured incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments.

Lessor — We have various arrangements for certain spaces for food service and vending equipment under which we are the lessor. These leases meet the criteria for operating lease classification. Lease income associated with these leases is immaterial.

Lessee —We lease land for 215 stations, one terminal, a hangar and various equipment. Our lease agreements do not contain any material residual value guarantees and approximately 102 sites leased from Walmart contain restrictive covenants, though the restrictions are deemed to have an immaterial impact.

Leases are reflected in the following balance sheet accounts:



(Millions of dollars)	Classification	December 31, 2019		December 31, 2018
Assets
Operating (Right-of-use)	Other Assets	$	124.2	$	—
Finance	Property, plant, and equipment, at cost, less accumulated depreciation of $2.2 in 2019 and$1.8 in 2018	3.0		2.9
Total leased assets		$	127.2	$	2.9

Liabilities
Current
Operating	Trade accounts payable and accrued liabilities	$	6.8	$	—
Finance	Current maturities of long-term debt	1.2		1.2
Noncurrent
Operating	Deferred credits and other liabilities	118.5		—
Finance	Long-term debt, including capitalized lease obligations	1.2		1.1
Total lease liabilities		$	127.7	$	2.3

Lease Cost:



		Year Ended December 31,
(Millions of dollars)	Classification	2019
Operating lease cost	Station and other operating expenses	$	14.5
Finance lease cost
Amortization of leased assets	Depreciation & amortization expense	1.2
Interest on lease liabilities	Interest expense	0.1
Net lease costs		$	15.8

Cash flow information:



	Year Ended December 31,
(Millions of dollars)	2019
Cash paid for amounts included in the measurement of liabilities
Operating cash flows required by operating leases	$	13.8
Operating cash flows required by finance leases	$	0.1
Financing cash flows required by finance leases	$	1.4

Maturity of Lease Liabilities:



(Millions of dollars)	Operating leases		Finance leases
2020	$	14.9	$	1.3
2021	14.3		0.9
2022	13.5		0.3
2023	13.0		—
2024	12.2		—
After 2024	148.9		—
Total lease payments	216.8		2.5
less: interest	91.5		0.1
Present value of lease liabilities	$	125.3	$	2.4

The Company adopted ASU 2016-02 on January 1, 2019, and as required, the following disclosure is provided for periods prior to adoption. Future annual minimum lease payments and capital lease commitments as of December 31, 2018 were as follows:



(Millions of dollars)	Operating leases		Capital leases
2019	$	13.7	$	1.5
2020	13.3		1.1
2021	12.5		0.6
2022	11.7		0.1
2023	11.1		—
After 2023	122.6		—
Total lease payments	184.9		3.3
less: interest	—		0.2
Present value of minimum payments	$	184.9	$	3.1

Lease Term and Discount Rate:



	Year Ended December 31,
	2019
Weighted average remaining lease term (years)
Finance leases	2.0
Operating leases	15.6
Weighted average discount rate
Finance leases	4.8	%
Operating leases	6.0	%

Recent Accounting and Reporting Rules	12 Months Ended
Recent Accounting and Reporting Rules	Dec. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting and Reporting Rules	Recent Accounting and Reporting Rules In August 2018, the FASB issued ASU 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract". This ASU aligns the accounting treatment for capitalizing implementation costs incurred by customers in cloud computing arrangements in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. This guidance is effective for the Company on January 1, 2020. Early adoption is permitted. The amendments in this update should be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. The Company has assessed the effect that this ASU will have on our financial position, results of operations, and disclosures and this update will not have a material impact on the Company's consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments." ASU 2016-13 was subsequently modified by ASU 2018-19, ASU 2019-04, ASU 2019-05, and ASU 2019-11. This ASU changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining life, which will result in timelier recognition of losses. ASU 2016-13 and the associated modifications will be effective for the Company on January 1, 2020. The Company has assessed the effect that this ASU will have on our financial position, results of operations, and disclosures and this update will not have a material impact on the Company's consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes," which removes certain exceptions for: recognizing deferred taxes on investments, performing intraperiod allocation and calculating income taxes for interim periods. The ASU also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. This ASU if effective for the Company for the year beginning January 1, 2021, and early adoption is permitted. The Company is currently assessing the effect that this ASU will have on our financial position, results of operations, and disclosures but does not expect this update to have a material impact on the Company's consolidated financial statements.

Business Segments

12 Months Ended

Dec. 31, 2019

Segment Reporting [Abstract]

Business Segments

Our operations include the sale of retail motor fuel products and convenience merchandise along with the wholesale and bulk sale capabilities of our product supply and wholesale group. As the primary purpose of the product supply and wholesale group is to support our retail operations and provide fuel for their daily operation, the bulk and wholesale fuel sales are secondary to the support functions played by these groups. As such, they are all treated as one segment for reporting purposes as they sell the same products. This Marketing segment contains essentially all of the revenue generating activities of the Company. Results not included in the reportable segment include Corporate and Other Assets. The reportable segment was determined based on information reviewed by the Chief Operating Decision Maker.



Segment Information				Corporate and
(Millions of dollars)	Marketing			Other Assets		Consolidated
Year ended December 31, 2019
Segment income (loss)	$	215.0		(60.2	)	$	154.8
Revenues from external customers	14,034.3			0.3		14,034.6
Interest income	—			3.2		3.2
Interest expense	(0.1		)	(54.8	)	(54.9		)
Loss on early debt extinguishment	—			(14.8	)	(14.8		)
Income tax expense (benefit)	66.3			(18.7	)	47.6
Significant noncash charges (credits)
Depreciation and amortization	138.9			13.3		152.2
Accretion of asset retirement obligations	2.1			—		2.1
Debt extinguishment costs	—			4.4		4.4
Deferred and noncurrent income taxes (benefits)	32.9			(9.2	)	23.7
Additions to property, plant and equipment	155.5			59.1		214.6
Total assets at year-end	$	2,304.7		382.5		$	2,687.2



Segment Information				Corporate and
(Millions of dollars)	Marketing			Other Assets		Consolidated
Year ended December 31, 2018
Segment income (loss)	$	214.2		(0.6	)	$	213.6
Revenues from external customers	14,362.3			0.6		14,362.9
Interest income	—			1.5		1.5
Interest expense	(0.1		)	(52.8	)	(52.9		)
Income tax expense (benefit)	69.5			(9.2	)	60.3
Significant noncash charges (credits)
Depreciation and amortization	124.5			9.5		134.0
Accretion of asset retirement obligations	2.0			—		2.0
Deferred and noncurrent income taxes (benefits)	39.0			(1.1	)	37.9
Additions to property, plant and equipment	169.2			24.6		193.8
Total assets at year-end	$	2,012.0		348.8		$	2,360.8



Segment Information				Corporate and
(Millions of dollars)	Marketing			Other Assets		Consolidated
Year ended December 31, 2017
Segment income (loss)	$	295.3		(50.0	)	$	245.3
Revenues from external customers	12,826.2			0.4		12,826.6
Interest income	—			1.3		1.3
Interest expense	(0.1		)	(46.6	)	(46.7		)
Income tax expense (benefit)	(2.9		)	(2.3	)	(5.2		)
Significant noncash charges (credits)
Depreciation and amortization	110.5			6.4		116.9
Accretion of asset retirement obligations	1.8			—		1.8
Deferred and noncurrent income taxes (benefits)	(61.3		)	10.9		(50.4		)
Additions to property, plant and equipment	234.0			39.7		273.7
Total assets at year-end	$	2,023.4		307.6		$	2,331.0

Guarantor Subsidiaries

12 Months Ended

Dec. 31, 2019

Guarantor Subsidiaries [Abstract]

Guarantor Subsidiaries

Certain of the Company’s 100% owned, domestic subsidiaries (the “Guarantor Subsidiaries”) fully and unconditionally guarantee, on a joint and several basis, certain of the outstanding indebtedness of the Company, including the 5.625% senior notes due 2027 and the 4.75% senior notes due 2029. The following consolidating schedules present financial information on a consolidated basis in conformity with the SEC’s Regulation S-X Rule 3-10(d):

CONSOLIDATING BALANCE SHEET



(Millions of dollars)	December 31, 2019
Assets	Parent Company			Issuer		Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Current assets
Cash and cash equivalents	$	—		$	279.4	$	0.9		$	—		$	—		$	280.3
Accounts receivable—trade, less allowance for doubtful accounts of $1.2 in 2019	—			173.0		(0.1		)	—			—			172.9
Inventories, at lower of cost or market	—			227.6		—			—			—			227.6
Prepaid expenses and other current assets	—			29.6		0.4			—			—			30.0
Total current assets	—			709.6		1.2			—			—			710.8
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019	—			1,799.1		8.2			—			—			1,807.3
Investments in subsidiaries	2,591.8			143.9		—			—			(2,735.7		)	—
Other assets	—			169.1		—			—			—			169.1
Total assets	$	2,591.8		$	2,821.7	$	9.4		$	—		$	(2,735.7	)	$	2,687.2
Liabilities and Stockholders' Equity
Current liabilities
Current maturities of long-term debt	$	—		$	38.8	$	—		$	—		$	—		$	38.8
Inter-company accounts payable	(0.1		)	196.1		(41.7		)	(154.3		)	—			—
Trade accounts payable and accrued liabilities	—			466.2		—			—			—			466.2
Total current liabilities	(0.1		)	701.1		(41.7		)	(154.3		)	—			505.0
Long-term debt, including capitalized lease obligations	—			999.3		—			—			—			999.3
Deferred income taxes	—			216.7		—			—			—			216.7
Asset retirement obligations	—			32.8		—			—			—			32.8
Deferred credits and other liabilities	—			130.4		—			—			—			130.4
Total liabilities	(0.1		)	2,080.3		(41.7		)	(154.3		)	—			1,884.2
Stockholders' Equity
Preferred Stock, par $0.01 (authorized 20,000,000 shares, none outstanding)	—			—		—			—			—			—
Common Stock, par $0.01 (authorized 200,000,000 shares, 46,767,164 shares issued at December 31, 2019)	0.5			—		0.1			—			(0.1		)	0.5
Treasury stock (16,307,048 shares held at December 31, 2019)	(1,099.8		)	—		—			—			—			(1,099.8		)
Additional paid in capital (APIC)	1,188.8			578.8		52.0			87.5			(1,368.4		)	538.7
Retained earnings	2,502.4			161.9		(1.0		)	66.8			(1,367.2		)	1,362.9
Accumulated other comprehensive income (AOCI)	—			0.7		—			—			—			0.7
Total stockholders' equity	2,591.9			741.4		51.1			154.3			(2,735.7		)	803.0
Total liabilities and stockholders' equity	$	2,591.8		$	2,821.7	$	9.4		$	—		$	(2,735.7	)	$	2,687.2

CONSOLIDATING BALANCE SHEET



(Millions of dollars)	December 31, 2018
Assets	Parent Company			Issuer		Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Current assets
Cash and cash equivalents	$	—		$	184.0	$	0.5		$	—		$	—		$	184.5
Accounts receivable—trade, less allowance for doubtful accounts of $1.1 in 2018	—			138.8		—			—			—			138.8
Inventories, at lower of cost or market	—			221.5		—			—			—			221.5
Prepaid expenses and other current assets	—			25.1		0.2			—			—			25.3
Total current assets	—			569.4		0.7			—			—			570.1
Property, plant and equipment, at cost less accumulated depreciation and amortization of $974.2 in 2018	—			1,745.9		2.3			—			—			1,748.2
Investments in subsidiaries	2,437.0			144.4		—			—			(2,581.4		)	—
Other assets	—			42.5		—			—			—			42.5
Total assets	$	2,437.0		$	2,502.2	$	3.0		$	—		$	(2,581.4	)	$	2,360.8
Liabilities and Stockholders' Equity
Current liabilities
Current maturities of long-term debt	$	—		$	21.2	$	—		$	—		$	—		$	21.2
Inter-company accounts payable	(0.1		)	203.0		(48.6		)	(154.3		)	—			—
Trade accounts payable and accrued liabilities	—			456.9		—			—			—			456.9
Total current liabilities	(0.1		)	681.1		(48.6		)	(154.3		)	—			478.1
Long-term debt, including capitalized lease obligations	—			842.1		—			—			—			842.1
Deferred income taxes	—			192.2		—			—			—			192.2
Asset retirement obligations	—			30.7		—			—			—			30.7
Deferred credits and other liabilities	—			10.4		—			—			—			10.4
Total liabilities	(0.1		)	1,756.5		(48.6		)	(154.3		)	—			1,553.5
Stockholders' Equity
Preferred Stock, par $0.01 (authorized 20,000,000 shares, none outstanding)	—			—		—			—			—			—
Common Stock, par $0.01 (authorized 200,000,000 shares, 46,767,164 shares issued at December 31, 2018)	0.5			—		0.1			—			(0.1		)	0.5
Treasury stock (14,505,681 shares held at December 31, 2018)	(940.3		)	—		—			—			—			(940.3		)
Additional paid in capital (APIC)	1,195.1			572.8		52.0			87.5			(1,368.4		)	539.0
Retained earnings	2,181.8			172.9		(0.5		)	66.8			(1,212.9		)	1,208.1
Accumulated other comprehensive income (AOCI)	—			—		—			—			—			—
Total stockholders' equity	2,437.1			745.7		51.6			154.3			(2,581.4		)	807.3
Total liabilities and stockholders' equity	$	2,437.0		$	2,502.2	$	3.0		$	—		$	(2,581.4	)	$	2,360.8

CONSOLIDATING INCOME STATEMENT AND COMPREHENSIVE INCOME



(Millions of dollars)	Year ended December 31, 2019
Operating Revenues	Parent Company		Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Petroleum product sales	$	—	$	11,373.8		$	—		$	—	$	—		$	11,373.8
Merchandise sales	—		2,620.1			—			—		—			2,620.1
Other operating revenues	—		40.7			—			—		—			40.7
Total operating revenues	—		14,034.6			—			—		—			14,034.6
Operating expenses
Petroleum product cost of goods sold	—		10,707.4			—			—		—			10,707.4
Merchandise cost of goods sold	—		2,200.7			—			—		—			2,200.7
Station and other operating expenses	—		559.3			—			—		—			559.3
Depreciation and amortization	—		152.1			0.1			—		—			152.2
Selling, general and administrative	—		144.6			—			—		—			144.6
Accretion of asset retirement obligations	—		2.1			—			—		—			2.1
Total operating expenses	—		13,766.2			0.1			—		—			13,766.3
Net settlement proceeds	—		0.1			—			—		—			0.1
Gain (loss) on sale of assets	—		0.1			—			—		—			0.1
Income from operations	—		268.6			(0.1		)	—		—			268.5
Other income (expense)
Interest income	—		3.2			—			—		—			3.2
Interest expense	—		(54.9		)	—			—		—			(54.9		)
Loss on early debt extinguishment	—		(14.8		)	—			—		—			(14.8		)
Other nonoperating income/expense	165.8		(164.8		)	(0.6		)	—		—			0.4
Total other income (expense)	165.8		(231.3		)	(0.6		)	—		—			(66.1		)
Income before income taxes	165.8		37.3			(0.7		)	—		—			202.4
Income tax expense (benefit)	—		47.8			(0.2		)	—		—			47.6
Income (loss)	165.8		(10.5		)	(0.5		)	—		—			154.8
Equity earnings in affiliates, net of tax	154.8		(0.5		)	—			—		(154.3		)	—
Net income (loss)	$	320.6	$	(11.0	)	$	(0.5	)	$	—	$	(154.3	)	$	154.8
Other comprehensive income	—		0.7			—			—		—			0.7
Comprehensive income (loss)	$	320.6	$	(10.3	)	$	(0.5	)	$	—	$	(154.3	)	$	155.5

CONSOLIDATING INCOME STATEMENT AND COMPREHENSIVE INCOME



(Millions of dollars)	Year ended December 31, 2018
Operating Revenues	Parent Company		Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Petroleum product sales	$	—	$	11,858.4		$	—		$	—	$	—		$	11,858.4
Merchandise sales	—		2,423.0			—			—		—			2,423.0
Ethanol sales and other	—		81.5			—			—		—			81.5
Total operating revenues	—		14,362.9			—			—		—			14,362.9
Operating Expenses
Petroleum product cost of goods sold	—		11,251.1			—			—		—			11,251.1
Merchandise cost of goods sold	—		2,022.5			—			—		—			2,022.5
Station and other operating expenses	—		541.3			—			—		—			541.3
Depreciation and amortization	—		134.0			—			—		—			134.0
Selling, general and administrative	—		136.2			—			—		—			136.2
Accretion of asset retirement obligations	—		2.0			—			—		—			2.0
Total operating expenses	—		14,087.1			—			—		—			14,087.1
Net settlement proceeds			50.4											50.4
Gain (loss) on sale of assets	—		(1.1		)	—			—		—			(1.1		)
Income from operations	—		325.1			—			—		—			325.1
Other income (expense)
Interest income	—		1.5			—			—		—			1.5
Interest expense	—		(52.9		)	—			—		—			(52.9		)
Other nonoperating income	973.7		(972.9		)	(0.6		)	—		—			0.2
Total other income (expense)	973.7		(1,024.3		)	(0.6		)	—		—			(51.2		)
Income before income taxes	973.7		(699.2		)	(0.6		)	—		—			273.9
Income tax expense (benefit)	—		60.4			(0.1		)	—		—			60.3
Income	973.7		(759.6		)	(0.5		)	—		—			213.6
Equity earnings in affiliates, net of tax	213.6		(0.5		)	—			—		(213.1		)	—
Net income (loss)	$	1,187.3	$	(760.1	)	$	(0.5	)	$	—	$	(213.1	)	$	213.6
Other comprehensive income	—		—			—			—		—			—
Comprehensive income (loss)	$	1,187.3	$	(760.1	)	$	(0.5	)	$	—	$	(213.1	)	$	213.6

CONSOLIDATING INCOME STATEMENT AND COMPREHENSIVE INCOME



(Millions of dollars)	Year ended December 31, 2017
Operating Revenues	Parent Company		Issuer			Guarantor Subsidiaries		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Petroleum product sales	$	—	$	10,287.9		$	—	$	—	$	—		$	10,287.9
Merchandise sales	—		2,372.7			—		—		—			2,372.7
Ethanol sales and other	—		166.0			—		—		—			166.0
Total operating revenues	—		12,826.6			—		—		—			12,826.6
Operating expenses
Petroleum product cost of goods sold	—		9,773.2			—		—		—			9,773.2
Merchandise cost of goods sold	—		1,991.4			—		—		—			1,991.4
Station and other operating expenses	—		514.9			—		—		—			514.9
Depreciation and amortization	—		116.9			—		—		—			116.9
Selling, general and administrative	—		141.2			—		—		—			141.2
Accretion of asset retirement obligations	—		1.8			—		—		—			1.8
Total operating expenses	—		12,539.4			—		—		—			12,539.4
Gain (loss) on sale of assets	—		(3.9		)	—		—		—			(3.9		)
Income from operations	—		283.3			—		—		—			283.3
Other income (expense)
Interest income	—		1.3			—		—		—			1.3
Interest expense	—		(46.7		)	—		—		—			(46.7		)
Other nonoperating income	—		2.2			—		—		—			2.2
Total other income (expense)	—		(43.2		)	—		—		—			(43.2		)
Income before income taxes	—		240.1			—		—		—			240.1
Income tax expense (benefit)	—		(5.2		)	—		—		—			(5.2		)
Income	—		245.3			—		—		—			245.3
Equity earnings in affiliates, net of tax	245.3		—			—		—		(245.3		)	—
Net income (loss)	$	245.3	$	245.3		$	—	$	—	$	(245.3	)	$	245.3
Other comprehensive income	—		—			—		—		—			—
Comprehensive income (loss)	$	245.3	$	245.3		$	—	$	—	$	(245.3	)	$	245.3

CONSOLIDATING STATEMENT OF CASH FLOWS



(Millions of dollars)	Year ended December 31, 2019
Operating Activities	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Net income (loss)	$	320.6		$	(11.0	)	$	(0.5	)	$	—	$	(154.3	)	$	154.8
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	—			152.1			0.1			—		—			152.2
Deferred and noncurrent income tax charges (benefits)	—			23.7			—			—		—			23.7
Accretion of asset retirement obligations	—			2.1			—			—		—			2.1
(Gain) loss from sale of assets	—			(0.1		)	—			—		—			(0.1		)
Net decrease (increase) in noncash operating working capital	—			(48.6		)	(0.1		)	—		—			(48.7		)
Equity in earnings	(154.8		)	0.5			—			—		154.3			—
Loss on early debt extinguishment	—			14.8			—			—		—			14.8
Other operating activities - net	—			14.5			—			—		—			14.5
Net cash provided by (required by) operating activities	165.8			148.0			(0.5		)	—		—			313.3
Investing Activities
Property additions	—			(198.8		)	(6.0		)	—		—			(204.8		)
Proceeds from sale of assets	—			2.5			—			—		—			2.5
Other investing activities - net	—			(0.8		)	—			—		—			(0.8		)
Net cash provided by (required by) investing activities	—			(197.1		)	(6.0		)	—		—			(203.1		)
Financing Activities
Purchase of treasury stock	(165.8		)	—			—			—		—			(165.8		)
Repayments of debt	—			(573.4		)	—			—		—			(573.4		)
Borrowings of debt	—			743.8			—			—		—			743.8
Early debt extinguishment costs	—			(10.4		)	—			—		—			(10.4		)
Debt issuance costs	—			(4.1		)	—			—		—			(4.1		)
Amounts related to share-based compensation	—			(4.5		)	—			—		—			(4.5		)
Net distributions to parent	—			(6.9		)	6.9			—		—			—
Net cash provided by (required by) financing activities	(165.8		)	144.5			6.9			—		—			(14.4		)
Net change in cash, cash equivalents, and restricted cash	—			95.4			0.4			—		—			95.8
Cash, cash equivalents, and restricted cash at January 1	—			184.0			0.5			—		—			184.5
Cash, cash equivalents, and restricted cash at December 31	$	—		$	279.4		$	0.9		$	—	$	—		$	280.3

Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and Cash equivalents at beginning of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5
Restricted cash at beginning of period	—			—			—			—		—			—
Cash, cash equivalents, and restricted cash at beginning of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5

Cash and cash equivalents at end of period	$	—		$	279.4		$	0.9		$	—	$	—		$	280.3
Restricted cash at end of period	—			—			—			—		—			—
Cash, cash equivalents, and restricted cash at end of period	$	—		$	279.4		$	0.9		$	—	$	—		$	280.3

CONSOLIDATING STATEMENT OF CASH FLOWS



(Millions of dollars)	Year ended December 31, 2018
Operating Activities	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Net income (loss)	$	1,187.3		$	(760.1	)	$	(0.5	)	$	—	$	(213.1	)	$	213.6
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	—			134.0			—			—		—			134.0
Deferred and noncurrent income tax charges (credits)	—			37.9			—			—		—			37.9
Accretion of asset retirement obligations	—			2.0			—			—		—			2.0
(Gains) loss from sale of assets	—			1.1			—			—		—			1.1
Net decrease (increase) in noncash operating working capital	—			2.4			(0.1		)	—		—			2.3
Equity in earnings	(213.6		)	0.5			—			—		213.1			—
Other operating activities - net	—			7.8			—			—		—			7.8
Net cash provided by (required by) operating activities	973.7			(574.4		)	(0.6		)	—		—			398.7
Investing Activities
Property additions	—			(203.1		)	(1.2		)	—		—			(204.3		)
Proceeds from sale of assets	—			1.2			—			—		—			1.2
Other investing activities - net	—			(6.0		)	—			—		—			(6.0		)
Net cash provided by (required by) investing activities	—			(207.9		)	(1.2		)	—		—			(209.1		)
Financing Activities
Purchase of treasury stock	(144.4		)	—			—			—		—			(144.4		)
Repayments of debt	—			(21.3		)	—			—		—			(21.3		)
Borrowings of debt	—			—			—			—		—			—
Debt issuance costs	—			—			—			—		—			—
Amounts related to share-based compensation	—			(9.4		)	—			—		—			(9.4		)
Net distributions to parent	(829.3		)	827.1			2.2			—		—			—
Net cash provided by (required by) financing activities	(973.7		)	796.4			2.2			—		—			(175.1		)
Net change in cash, cash equivalents, and restricted cash	—			14.1			0.4			—		—			14.5
Cash, cash equivalents, and restricted cash at January 1	—			169.9			0.1			—		—			170.0
Cash, cash equivalents, and restricted cash at December 31	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5

Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents at beginning of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0
Restricted cash at beginning of period	—			—			—			—		—			—
Cash, cash equivalents and restricted cash at beginning of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0

Cash and cash equivalents at end of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5
Restricted cash at end of period	—			—			—			—		—			—
Cash, cash equivalents and restricted cash at end of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5

CONSOLIDATING STATEMENT OF CASH FLOWS



(Millions of dollars)	Year ended December 31, 2017
Operating Activities	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Net income (loss)	$	245.3		$	245.3		$	—		$	—	$	(245.3	)	$	245.3
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	—			116.9			—			—		—			116.9
Deferred and noncurrent income tax charges (credits)	—			(50.4		)	—			—		—			(50.4		)
Accretion of asset retirement obligations	—			1.8			—			—		—			1.8
(Gains) loss from sale of assets	—			3.9			—			—		—			3.9
Net decrease (increase) in noncash operating working capital	—			(36.9		)	—			—		—			(36.9		)
Equity in earnings	(245.3		)	—			—			—		245.3			—
Other operating activities - net	—			3.0			—			—		—			3.0
Net cash provided by (required by) operating activities	—			283.6			—			—		—			283.6
Investing Activities
Property additions	—			(257.1		)	(1.2		)	—		—			(258.3		)
Proceeds from sale of assets	—			0.9			—			—		—			0.9
Other investing activities - net	—			(4.7		)	—			—		—			(4.7		)
Net cash provided by (required by) investing activities	—			(260.9		)	(1.2		)	—		—			(262.1		)
Financing Activities
Purchase of treasury stock	(206.0		)	—			—			—		—			(206.0		)
Repayments of debt	—			(131.4		)	—			—		—			(131.4		)
Borrowings of debt	—			338.8			—			—		—			338.8
Debt issuance costs	—			(1.1		)	—			—		—			(1.1		)
Amounts related to share-based compensation	—			(5.6		)	—			—		—			(5.6		)
Net distributions to parent	206.0			(207.3		)	1.3			—		—			—
Net cash provided by (required by) financing activities	—			(6.6		)	1.3			—		—			(5.3		)
Net change in cash, cash equivalents, and restricted cash	—			16.1			0.1			—		—			16.2
Cash, cash equivalents and restricted cash at January 1	—			153.8			—			—		—			153.8
Cash, cash equivalents and restricted cash at December 31	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0

Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents at beginning of period	$	—		$	153.8		$	—		$	—	$	—		$	153.8
Restricted cash at beginning of period	—			—			—			—		—			—
Cash, cash equivalents and restricted cash at beginning of period	$	—		$	153.8		$	—		$	—	$	—		$	153.8

Cash and cash equivalents at end of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0
Restricted cash at end of period	—			—			—			—		—			$	—
Cash, cash equivalents and restricted cash at end of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0

CONSOLIDATING STATEMENT OF CHANGES IN EQUITY



(Millions of dollars)	Year ended December 31, 2019
Statement of Stockholders' Equity	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Common Stock
Balance as of December 31, 2018	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Issuance of common stock	—			—			—			—		—			—
Balance as of December 31, 2019	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Treasury Stock
Balance as of December 31, 2018	$	(940.3	)	$	—		$	—		$	—	$	—		$	(940.3	)
Issuance of treasury stock	6.3			—			—			—		—			6.3
Purchase of treasury stock	(165.8		)	—			—			—		—			(165.8		)
Balance as of December 31, 2019	$	(1,099.8	)	$	—		$	—		$	—	$	—		$	(1,099.8	)
APIC
Balance as of December 31, 2018	$	1,195.1		$	572.8		$	52.0		$	87.5	$	(1,368.4	)	$	539.0
Issuance of treasury stock	(6.3		)	—			—			—		—			(6.3		)
Amounts related to share-based compensation	—			(4.5		)	—			—		—			(4.5		)
Share-based compensation expense	—			10.5			—			—		—			10.5
Balance as of December 31, 2019	$	1,188.8		$	578.8		$	52.0		$	87.5	$	(1,368.4	)	$	538.7
Retained Earnings
Balance as of December 31, 2018	$	2,181.8		$	172.9		$	(0.5	)	$	66.8	$	(1,212.9	)	$	1,208.1
Net income	320.6			(11.0		)	(0.5		)	—		(154.3		)	154.8
Balance as of December 31, 2019	$	2,502.4		$	161.9		$	(1.0	)	$	66.8	$	(1,367.2	)	$	1,362.9
AOCI
Balance as of December 31, 2018	$	—		$	—		$	—		$	—	$	—		$	—
Other comprehensive income	—			0.7			—			—		—			0.7
Balance as of December 31, 2019	$	—		$	0.7		$	—		$	—	$	—		$	0.7

CONSOLIDATING STATEMENTS OF CHANGES IN EQUITY



(Millions of dollars)	Year ended December 31, 2018
Statement of Stockholders' Equity	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Common Stock
Balance as of December 31, 2017	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Issuance of common stock	—			—			—			—		—			—
Balance as of December 31, 2018	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Treasury Stock
Balance as of December 31, 2017	$	(806.5	)	$	—		$	—		$	—	$	—		$	(806.5	)
Issuance of treasury stock	10.6			—			—			—		—			10.6
Purchase of treasury stock	(144.4		)	—			—			—		—			(144.4		)
Balance as of December 31, 2018	$	(940.3	)	$	—		$	—		$	—	$	—		$	(940.3	)
APIC
Balance as of December 31, 2017	$	1,205.7		$	573.1		$	52.0		$	87.5	$	(1,368.4	)	$	549.9
Issuance of treasury stock	(10.6		)	—			—			—		—			(10.6		)
Amounts related to share-based compensation	—			(9.4		)	—			—		—			(9.4		)
Share-based compensation expense	—			9.1			—			—		—			9.1
Balance as of December 31, 2018	$	1,195.1		$	572.8		$	52.0		$	87.5	$	(1,368.4	)	$	539.0
Retained Earnings
Balance as of December 31, 2017	$	994.5		$	933.0		$	—		$	66.8	$	(999.8	)	$	994.5
Net income	1,187.3			(760.1		)	(0.5		)	—		(213.1		)	213.6
Balance as of December 31, 2018	$	2,181.8		$	172.9		$	(0.5	)	$	66.8	$	(1,212.9	)	$	1,208.1
AOCI
Balance as of December 31, 2017	$	—		$	—		$	—		$	—	$	—		$	—
Other comprehensive income	—			—			—			—		—			—
Balance as of December 31, 2018	$	—		$	—		$	—		$	—	$	—		$	—

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY



(Millions of dollars)	Year ended December 31, 2017
Statement of Stockholders' Equity	Parent Company			Issuer			Guarantor Subsidiaries		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Common Stock
Balance as of December 31, 2016	$	0.5		$	—		$	0.1	$	—	$	(0.1	)	$	0.5
Issuance of common stock	—			—			—		—		—			—
Balance as of December 31, 2017	$	0.5		$	—		$	0.1	$	—	$	(0.1	)	$	0.5
Treasury Stock
Balance as of December 31, 2016	$	(608.0	)	$	—		$	—	$	—	$	—		$	(608.0	)
Issuance of treasury stock	7.5			—			—		—		—			7.5
Purchase of treasury stock	(206.0		)	—			—		—		—			(206.0		)
Balance as of December 31, 2017	$	(806.5	)	$	—		$	—	$	—	$	—		$	(806.5	)
APIC
Balance as of December 31, 2016	$	1,213.1		$	571.1		$	52.0	$	87.5	$	(1,368.4	)	$	555.3
Issuance of treasury stock	(7.4		)	—			—		—		—			(7.4		)
Amounts related to share-based compensation	—			(5.6		)	—		—		—			(5.6		)
Share-based compensation expense	—			7.6			—		—		—			7.6
Balance as of December 31, 2017	$	1,205.7		$	573.1		$	52.0	$	87.5	$	(1,368.4	)	$	549.9
Retained Earnings
Balance as of December 31, 2016	$	749.2		$	687.7		$	—	$	66.8	$	(754.5	)	$	749.2
Net income	245.3			245.3			—		—		(245.3		)	245.3
Balance as of December 31, 2017	$	994.5		$	933.0		$	—	$	66.8	$	(999.8	)	$	994.5
AOCI
Balance as of December 31, 2016	$	—		$	—		$	—	$	—	$	—		$	—
Other comprehensive income	—			—			—		—		—			—
Balance as of December 31, 2017	$	—		$	—		$	—	$	—	$	—		$	—

Supplemental Quarterly Information (Unaudited)

12 Months Ended

Dec. 31, 2019

Supplemental Quarterly Information (Unaudited)



	First		Second		Third		Fourth
(Millions of dollars except per share amounts)	Quarter		Quarter		Quarter		Quarter		Year
Year Ended December 31, 2019
Sales and other operating revenues	$	3,116.4	$	3,800.4	$	3,657.6	$	3,460.2	$	14,034.6
Income (loss) from continuing operations before income taxes	$	5.9	$	43.3	$	91.3	$	61.9	$	202.4
Income (loss) from continuing operations	$	5.3	$	32.7	$	69.2	$	47.6	$	154.8
Net income (loss)	$	5.3	$	32.7	$	69.2	$	47.6	$	154.8
Income (loss) from continuing operations (per Common share)
Basic	$	0.16	$	1.02	$	2.20	$	1.56	$	4.90
Diluted	$	0.16	$	1.01	$	2.18	$	1.54	$	4.86
Net income (loss) (per Common share)
Basic	$	0.16	$	1.02	$	2.20	$	1.56	$	4.90
Diluted	$	0.16	$	1.01	$	2.18	$	1.54	$	4.86

Year Ended December 31, 2018
Sales and other operating revenues	$	3,244.2	$	3,829.0	$	3,788	$	3,501.7	$	14,362.9
Income (loss) from continuing operations before income taxes	$	47.3	$	69.1	$	57.0	$	100.5	$	273.9
Income (loss) from continuing operations	$	39.3	$	51.8	$	45.0	$	77.5	$	213.6
Net income (loss)	$	39.3	$	51.8	$	45.0	$	77.5	$	213.6
Income (loss) from continuing operations (per Common share)
Basic	$	1.17	$	1.59	$	1.40	$	2.40	$	6.54
Diluted	$	1.16	$	1.58	$	1.38	$	2.38	$	6.48
Net income (loss) (per Common share)
Basic	$	1.17	$	1.59	$	1.40	$	2.40	$	6.54
Diluted	$	1.16	$	1.58	$	1.38	$	2.38	$	6.48

Schedule II - Valuation And Qualifying Accounts

12 Months Ended

Dec. 31, 2019

SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]

Schedule II - Valuation And Qualifying Accounts

SCHEDULE II – VALUATION AND QUALIFYING ACCOUNTS

Murphy USA Inc.

Valuation Accounts and Reserves



(Millions of dollars)	Balance at January 1,		Charged (Credited) to Expense		Deductions		Balance at December 31,

2019
Deducted from assets accounts
Allowance for doubtful accounts	$	1.1	0.1				1.2

2018
Deducted from assets accounts
Allowance for doubtful accounts	$	1.1	0.5		(0.5	)	1.1

2017
Deducted from assets accounts
Allowance for doubtful accounts	$	1.9	(0.8	)	—		1.1

Significant Accounting Policies (Policies)	12 Months Ended
Significant Accounting Policies (Policies)	Dec. 31, 2019
Accounting Policies [Abstract]
Principles of Consolidation	PRINCIPLES OF CONSOLIDATION – These consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and include the accounts of Murphy USA Inc. and its subsidiaries for all periods presented. All significant intercompany accounts and transactions within the consolidated financial statements have been eliminated.
Revenue Recognition, Shipping and Handling Costs and Vendor Allowances and Rebates	VENDOR ALLOWANCES AND REBATES – Murphy USA receives payments for vendor allowances, volume rebates and other related payments from various suppliers of its convenience store merchandise. Vendor allowances for price markdowns are credited to merchandise cost of goods sold during the period the related markdown is recognized. Volume rebates of merchandise are recorded as reductions to merchandise cost of goods sold when the merchandise qualifying for the rebate is sold. Slotting and stocking allowances received from a vendor are recorded as a reduction to cost of sales over the period covered by the agreement. REVENUE RECOGNITION – Revenue is recognized when obligations under the terms of a contract with our customers are satisfied; generally, this occurs with the transfer of control of our petroleum products, convenience merchandise, Renewable Identification Numbers ("RINs") and other assets to our third-party customers. Revenue is measured as the amounts of consideration we expect to receive in exchange for transferring goods or providing services. Excise and sales tax that we collect where we have determined we are the principal in the transaction have been recorded as revenue on a jurisdiction-by-jurisdiction basis. The Company enters into buy/sell and similar arrangements when petroleum products are held at one location but are needed at a different location. The Company often pays or receives funds related to the buy/sell arrangement based on location or quality differences. The Company accounts for such transactions on a net basis in its Consolidated Income Statements. See Note 3 "Revenues" for additional information. SHIPPING AND HANDLING COSTS – Costs incurred for the shipping and handling of motor fuel are included in Petroleum product cost of goods sold in the Consolidated Income Statements. Costs incurred for the shipping and handling of convenience store merchandise are included in Merchandise cost of goods sold in the Consolidated Income Statements. Petroleum product sales (at retail). For our retail store locations, the revenue related to petroleum product sales is recognized as the fuel is pumped to our customers. The transaction price at the pump typically includes some portion of sales or excise taxes as levied in the respective jurisdictions. Those taxes that are collected for remittance to governmental entities on a pass through basis are not recognized as revenue and they are recorded to a liability account until they are paid. Our customers typically use a mixture of cash, checks, credit cards and debit cards to pay for our products as they are received. We have accounts receivable from the various credit/debit card providers at any point in time related to product sales made on credit cards and debit cards. These receivables are typically collected in two to seven days, depending on the terms with the particular credit/debit card providers. Payment fees retained by the credit/debit card providers are recorded as station and other operating expenses. Petroleum product sales (at wholesale). Our sales of petroleum products at wholesale are generally recorded as revenue when the deliveries have occurred and legal ownership of the product has transferred to the customer. Title transfer for bulk refined product sales typically occurs at pipeline custody points and upon trucks loading at product terminals. For bulk pipeline sales, we record receivables from customers that are generally collected within a week from custody transfer date. For our rack product sales, the majority of our customers' accounts are drafted by us within 10 days from product transfer. Merchandise sales. For our retail store locations, the revenue related to merchandise sales is recognized as the customer completes their purchase at our locations. The transaction price typically includes some portion of sales tax as levied in the respective jurisdictions. Those taxes that are collected for remittance to governmental entities on a pass through basis are not recognized as revenue and they are recorded to a liability account until they are paid. As noted above, a mixture of payment types are used for these revenues and the same terms for credit/debit card receivables are realized. The most significant judgment with respect to merchandise sales revenue is determining whether we are the principal or agent for some categories of merchandise such as lottery tickets, lotto tickets, newspapers and other small categories of merchandise. For scratch-off lottery tickets, we have determined we are the principal in the majority of the jurisdictions and therefore we record those sales on a gross basis. We have some categories of merchandise (such as lotto tickets) where we are the agent and the revenues recorded for those transactions are our net commission only. In June 2018 the Company initiated a loyalty pilot program through a limited number of its retail locations and was rolled out chain-wide in March 2019. The customers earn rewards based on their spending or other promotional activities. This program creates a performance obligation which requires us to defer a portion of sales revenue to the loyalty program participants until they redeem their rewards. The rewards may be redeemed for free or discounted merchandise or cash discounts on fuel purchases. Earned rewards expire after an account is inactive for a period of 90 days. We recognize loyalty revenue when a customer redeems an earned reward. Deferred revenue associated with Murphy Rewards is included in Trade accounts payable and accrued liabilities in our Consolidated Balance Sheet. The deferred revenues recorded in 2019 and 2018 were immaterial. RINs sales. For the sale of RINs, we recognize revenue when the RIN is transferred to the counter-party and the sale is completed. Receivables from our counter-parties related to the RIN sales are typically collected within five days of the sale. Other revenues. Items reported as other operating revenues include collection allowances for excise and sales tax and other miscellaneous items and are recognized as revenue when the transaction is completed. The Company adopted ASC Topic 606, "Revenue from Contracts with Customers" as of January 1, 2018 using the modified retrospective method applied to those contracts which were not completed as of January 1, 2018. Results for reporting periods beginning after January 1, 2018 are presented under Topic 606, while prior period amounts are not adjusted and continue to be reported in accordance with our historical accounting policies under Topic 605.
Taxes Collected from Customers and Remitted to Government Authorities	TAXES COLLECTED FROM CUSTOMERS AND REMITTED TO GOVERNMENT AUTHORITIES – Excise and other taxes collected on sales of refined products and remitted to governmental agencies are included in operating revenues and operating expenses in the Consolidated Income Statements.
Cash Equivalents	CASH EQUIVALENTS – Short-term investments, which include government securities, money market funds and other instruments with government securities as collateral, that have a maturity of three months or less from the date of purchase are classified as cash equivalents.
Accounts Receivable	ACCOUNTS RECEIVABLE – The Company’s accounts receivable are recorded at the invoiced amount and do not bear interest. The accounts receivable primarily consists of amounts owed to the Company from credit card companies and by customers for wholesale sales of refined petroleum products. The allowance for doubtful accounts is the Company’s best estimate of the amount of probable credit losses on these receivables. The Company reviews this allowance for adequacy at least quarterly and bases its assessment on a combination of current information about its customers and historical write-off experience. Any trade accounts receivable balances written off are charged against the allowance for doubtful accounts. The Company has not experienced any significant credit-related losses in the past three years.
Inventories	INVENTORIES – Inventories of most finished products are valued at the lower of cost, generally applied on a last-in, first-out (“LIFO”) basis, or market. Any increments to LIFO inventory volumes are valued based on the first purchase price for these volumes during the year. Merchandise inventories held for resale are carried at average cost. Materials and supplies are valued at the lower of average cost or estimated value.
Property, Plant and Equipment	PROPERTY, PLANT AND EQUIPMENT – Additions to property, plant and equipment, including renewals and betterments, are capitalized and recorded at cost. Certain marketing facilities are primarily depreciated using the composite straight-line method with depreciable lives ranging from 16 to 25 years. Gasoline stations, improvements to gasoline stations and other assets are depreciated over 3 to 50 years by individual unit on the straight-line method. The Company capitalizes interest costs as a component of construction in progress on individually significant projects based on the weighted average interest rates incurred on its long-term borrowings. Total interest cost capitalized in 2019 was $1.4 million, $2.2 million in 2018 and $3.8 million in 2017. The Company has undertaken like-kind exchange ("LKE") transactions under the Federal tax code in an effort to acquire and sell real and personal property in a tax efficient manner. The Company generally enters into forward transactions, in which property is sold and the proceeds are reinvested by acquiring similar property; and reverse transactions, in which property is acquired and similar property is subsequently sold. A qualified LKE intermediary is used to facilitate these LKE transactions. Proceeds from forward LKE transactions are held by the intermediary and are classified as restricted cash on the Company's balance sheet because the funds must be reinvested in similar properties. If the acquisition of suitable LKE properties is not completed within 180 days of the sale of the Company-owned property, the proceeds are distributed to the Company by the intermediary and are reclassified as available cash and applicable income taxes are determined. An exchange accommodation titleholder, a type of variable interest entity, is used to facilitate reverse like-kind exchanges. The acquired assets are held by the exchange accommodation titleholder until the exchange transactions are complete. If the Company determines that it is the primary beneficiary of the exchange accommodation titleholder, the replacements assets held by the exchange accommodation titleholder are consolidated and recorded in Property, Plant and Equipment on the Consolidated Balance Sheets. The unspent proceeds that are held in trust with the intermediary are recorded as noncurrent assets in the Consolidated Balance Sheet as the cash was restricted for the acquisition of property, plant and equipment.
Impairment of Assets	IMPAIRMENT OF ASSETS – Long-lived assets, which include property and equipment and finite-lived intangible assets, are tested for recoverability whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. A long-lived asset is not recoverable if its carrying amount exceeds the sum of the undiscounted cash flows expected to result from its use and eventual disposition. If a long-lived asset is not recoverable, an impairment loss is recognized for the amount by which the carrying amount of the long-lived asset exceeds its fair value, with fair value determined based on discounted estimated net cash flows or other appropriate methods.
Asset Retirement Obligations	ASSET RETIREMENT OBLIGATIONS – The Company records a liability for asset retirement obligations (“ARO”) equal to the fair value of the estimated cost to retire an asset. The ARO liability is initially recorded in the period in which the obligation meets the definition of a liability, which is generally when the asset is placed in service. The ARO liability is estimated using existing regulatory requirements and anticipated future inflation rates. When the liability is initially recorded, the Company increases the carrying amount of the related long-lived asset by an amount equal to the original liability. The liability is increased over time to reflect the change in its present value, and the capitalized cost is depreciated over the useful life of the related long-lived asset. The Company reevaluates the adequacy of its recorded ARO liability at least annually. Actual costs of asset retirements such as dismantling service stations and site restoration are charged against the related liability. Any difference between costs incurred upon settlement of an asset retirement obligation and the recorded liability is recognized as a gain or loss in the Company’s Consolidated Income Statements.
Environmental Liabilities	ENVIRONMENTAL LIABILITIES – A liability for environmental matters is established when it is probable that an environmental obligation exists and the cost can be reasonably estimated. If there is a range of reasonably estimated costs, the most likely amount will be recorded, or if no amount is most likely, the minimum of the range is used. Related expenditures are charged against the liability. Environmental remediation liabilities have not been discounted for the time value of future expected payments. Environmental expenditures that have future economic benefit are capitalized.
Income Taxes	INCOME TAXES – The Company accounts for income taxes using the asset and liability method. Under this method, income taxes are provided for amounts currently payable and for amounts deferred as tax assets and liabilities based on differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities. Deferred income taxes are measured using the enacted tax rates that are assumed will be in effect when the differences reverse. The Company routinely assesses the realizability of deferred tax assets based on available positive and negative evidence including assumptions of future taxable income, tax planning strategies and other pertinent factors. A deferred tax asset valuation allowance is recorded when evidence indicates that it is more likely than not that all or a portion of these deferred tax assets will not be realized in a future period. The accounting principles for income tax uncertainties permit recognition of income tax benefits only when they are more likely than not to be realized. The Company has elected to classify any interest expense and penalties related to the underpayment of income taxes in Income tax expense in the Consolidated Income Statements.
Derivative Instruments and Hedging Activities	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES – The fair value of a derivative instrument is recognized as an asset or liability in the Company’s Consolidated Balance Sheets. Upon entering into a derivative contract, the Company may designate the derivative as either a fair value hedge or a cash flow hedge, or decide that the contract is not a hedge, and therefore, recognize changes in the fair value of the contract in earnings. The Company documents the relationship between the derivative instrument designated as a hedge and the hedged items as well as its objective for risk management and strategy for use of the hedging instrument to manage the risk. Derivative instruments designated as fair value or cash flow hedges are linked to specific assets and liabilities or to specific firm commitments or forecasted transactions. The Company assesses at inception and on an ongoing basis whether a derivative instrument accounted for as a hedge is highly effective in offsetting changes in the fair value or cash flows of the hedged item. A derivative that is not a highly effective hedge does not qualify for hedge accounting. The change in the fair value of a qualifying fair value hedge is recorded in earnings along with the gain or loss on the hedged item. The effective portion of the change in the fair value of a qualifying cash flow hedge is recorded in Accumulated other comprehensive income (AOCI) in the consolidated Balance Sheets until the hedged item is recognized currently in earnings. If a derivative instrument no longer qualifies as a cash flow hedge and the underlying forecasted transaction is no longer probable of occurring, hedge accounting is discontinued and the gain or loss recorded in Accumulated other comprehensive income is recognized immediately in earnings.
Stock-Based Compensation	STOCK-BASED COMPENSATION – The fair value of awarded stock options, restricted stock, restricted stock units and performance stock units is determined based on a combination of management assumptions for awards issued. The Company uses the Black-Scholes option pricing model for computing the fair value of stock options. The primary assumptions made by management included the expected life of the stock option award and the expected volatility of the Company’s common stock prices. The Company uses both historical data and current information to support its assumptions. Stock option expense is recognized on a straight-line basis over the requisite service period of three years. The Company uses a Monte Carlo valuation model to determine the fair value of performance-based stock units that are based on performance compared against a peer group and the related expense is recognized over the three-year requisite service period. Management estimates the number of all award that will not vest and adjusts its compensation expense accordingly. Differences between estimated and actual vested amounts are accounted for as an adjustment to expense when known.
Use of Estimates	USE OF ESTIMATES – In preparing the financial statements of the Company in conformity with U.S. GAAP, management has made a number of estimates and assumptions related to the reporting of assets, liabilities, revenues, and expenses and the disclosure of contingent assets and liabilities. Actual results may differ from the estimates. On an ongoing basis, we review our estimates based on currently available information. Changes in facts and circumstances may result in revised estimates.
Recent Accounting and Reporting Rules	Recent Accounting and Reporting Rules In August 2018, the FASB issued ASU 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract". This ASU aligns the accounting treatment for capitalizing implementation costs incurred by customers in cloud computing arrangements in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. This guidance is effective for the Company on January 1, 2020. Early adoption is permitted. The amendments in this update should be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. The Company has assessed the effect that this ASU will have on our financial position, results of operations, and disclosures and this update will not have a material impact on the Company's consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments." ASU 2016-13 was subsequently modified by ASU 2018-19, ASU 2019-04, ASU 2019-05, and ASU 2019-11. This ASU changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining life, which will result in timelier recognition of losses. ASU 2016-13 and the associated modifications will be effective for the Company on January 1, 2020. The Company has assessed the effect that this ASU will have on our financial position, results of operations, and disclosures and this update will not have a material impact on the Company's consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes," which removes certain exceptions for: recognizing deferred taxes on investments, performing intraperiod allocation and calculating income taxes for interim periods. The ASU also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. This ASU if effective for the Company for the year beginning January 1, 2021, and early adoption is permitted. The Company is currently assessing the effect that this ASU will have on our financial position, results of operations, and disclosures but does not expect this update to have a material impact on the Company's consolidated financial statements.
Lease Accounting	The Company determines if an arrangement is a lease or contains a lease at inception. Operating lease right-of-use assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Leases with an initial term of 12 months or less are not recorded on the balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. The Company's leases have remaining lease terms of approximately 1 year to 20 years, which may include the option to extend the lease when it is reasonably certain the Company will exercise the option. Most leases include one or more options to renew, with renewal terms that can extend the lease term from five to 20 years or more. The exercise of lease renewal options is at the Company's sole discretion. Due to the uncertainties of future markets, economic factors, technology changes, demographic shifts and behavior, environmental regulatory requirements and other information that impacts decisions as to station location, management has determined that it was not reasonably certain to exercise contract options and they are not included in the lease term. Additionally, short-term leases and leases with variable lease costs are immaterial. The Company reviews all options to extend, terminate, or otherwise modify its lease agreements to determine if changes are required to the right of use assets and liabilities. As the implicit interest rate is not readily determinable in most of the Company's lease agreements, the Company uses its estimated secured incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments.

Revenues (Tables)

12 Months Ended

Dec. 31, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

The following table disaggregates our revenue by major source for the years ended December 31, 2019, 2018, and 2017.



	Years Ended December 31,
(Millions of dollars)	2019		2018		2017
Marketing Segment
Petroleum product sales (at retail) ¹	$	10,184.0	$	10,459.2	$	9,041.5
Petroleum product sales (at wholesale) ¹	1,189.8		1,399.2		1,246.4
Total petroleum product sales	11,373.8		11,858.4		10,287.9
Merchandise sales	2,620.1		2,423.0		2,372.6
Other operating revenues:
RINs	34.8		75.2		160.3
Other revenues ²	5.6		5.7		5.4
Total marketing segment revenues	14,034.3		14,362.3		$	12,826.2
Corporate and Other Assets	0.3		0.6		$	0.4
Total revenues	$	14,034.6	$	14,362.9	$	12,826.6

¹ Includes excise and sales taxes that remain eligible for inclusion under Topic 606

² Primarily includes collection allowance on excise and sales taxes and other miscellaneous items

Inventories (Tables)

12 Months Ended

Dec. 31, 2019

Inventory Disclosure [Abstract]

Summary of Inventory

Inventories consisted of the following:



	December 31,
(Millions of dollars)	2019			2018
Finished products - FIFO basis	$	259.2		$	219.4
Less LIFO reserve - finished products	(160.8		)	(115.5		)
Finished products - LIFO basis	98.4			103.9
Store merchandise for resale	123.0			107.2
Materials and supplies	6.2			10.4
Total inventories	$	227.6		$	221.5

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2019

Property, Plant and Equipment [Abstract]

Summary of Property, Plant and Equipment



		December 31, 2019				December 31, 2018
(Millions of dollars)	Estimated Useful Life	Cost		Net		Cost		Net
Land		$	598.6	$	598.6	$	591.9	$	591.9
Pipeline and terminal facilities	16 to 25 years	77.5		43.7		73.1		41.6
Retail gasoline stations	3 to 50 years	2,034.4		1,073.6		1,890.6		1,018.5
Buildings	20 to 45 years	60.5		44.9		55.0		41.8
Other	3 to 20 years	115.5		46.5		111.8		54.4
		$	2,886.5	$	1,807.3	$	2,722.4	$	1,748.2

Accounts Payable And Accrued Liabilities (Tables)

12 Months Ended

Dec. 31, 2019

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Liabilities

Trade accounts payable and accrued liabilities consisted of the following:



	December 31,
(Millions of dollars)	2019		2018
Trade accounts payable	$	280.8	$	274.9
Excise taxes/withholdings payable	86.2		89.7
Accrued insurance obligations	24.4		21.8
Accrued taxes other than income	25.6		26.6
Other	49.2		43.9
Accounts payable and accrued liabilities	$	466.2	$	456.9

Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Summary of Long-Term Debt

Long-term debt consisted of the following:



	December 31,
(Millions of dollars)	2019			2018
6.00% senior notes due 2023 (net of unamortized discount of $4.1 at 2018)	$	—		$	495.9
5.625% senior notes due 2027 (net of unamortized discount of $2.7 at 2019 and $3.1 at 2018)	297.3			296.9
4.75 % senior notes due 2029 (net of unamortized discount of $6.1 at 2019)	493.9			—
Term loan due 2020 (effective interest rate of 5.0% at 2018 )	—			72.0
Term loan due 2023 (effective interest rate of 4.3% at 2019)	250.0			—
Capitalized lease obligations, vehicles, due through 2022	2.4			2.3
Unamortized debt issuance costs	(5.5		)	(3.8		)
Total long-term debt	1,038.1			863.3
Less current maturities	38.8			21.2
Total long-term debt, net of current	$	999.3		$	842.1

Asset Retirement Obligations (ARO) (Tables)

12 Months Ended

Dec. 31, 2019

Asset Retirement Obligation Disclosure [Abstract]

Reconciliation of Beginning and Ending Aggregate Carrying Amount of Asset Retirement Obligation

A reconciliation of the beginning and ending aggregate carrying amount of the ARO is shown in the following table.



	December 31,
(Millions of dollars)	2019			2018
Balance at beginning of period	$	30.7		$	28.2
Accretion expense	2.1			2.0
Settlement of liabilities	(0.4		)	(0.3		)
Liabilities incurred	0.4			0.8
Balance at end of period	$	32.8		$	30.7

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Summary of Effective Income Tax Rates

The components of income before income taxes for each of the three years ended December 31, 2019 and income tax expense (benefit) attributable thereto were as follows:



	Years Ended December 31,
(Millions of dollars)	2019		2018		2017
Income (loss) before income taxes	$	202.4	$	273.9	$	240.1
Income tax expense (benefit)
Federal - Current	$	15.6	18.4		39.2
Federal - Deferred	21.7		31.0		(50.7		)
State - Current and deferred	10.3		10.9		6.3
Total	$	47.6	$	60.3	$	(5.2	)

Schedule of Reconciliation of Income Taxes to Statutory Rate

The following table reconciles income taxes based on the U.S. statutory tax rate to the Company’s income tax expense (benefit).



	Years Ended December 31,
(Millions of dollars)	2019			2018			2017
Income tax expense based on the U.S. statutory tax rate	$	42.5		$	57.5		$	84.0
State income taxes, net of federal benefit	8.6			8.3			3.0
Effect of U.S. tax law change	—			—			(88.9		)
Federal credits	(2.3		)	(2.0		)	(1.0		)
Other, net	(1.2		)	(3.5		)	(2.3		)
Total	$	47.6		$	60.3		$	(5.2	)

Summary of Deferred Tax Assets and Deferred Tax Liabilities

An analysis of the Company’s deferred tax assets and deferred tax liabilities at December 31, 2019 and 2018 showing the tax effects of significant temporary differences is as follows:



	December 31,
(Millions of dollars)	2019			2018
Deferred tax assets
Property costs and asset retirement obligations	$	3.7		$	3.3
Employee benefits	6.1			6.3
Operating leases liability	25.0			—
Other deferred tax assets	2.1			2.6
Total gross deferred tax assets	36.9			12.2
Deferred tax liabilities
Accumulated depreciation and amortization	(191.2		)	(171.6		)
State deferred taxes	(27.9		)	(25.9		)
Operating leases right of use assets	(24.8		)	—
Other deferred tax liabilities	(9.7		)	(6.9		)
Total gross deferred tax liabilities	(253.6		)	(204.4		)
Net deferred tax liabilities	$	(216.7	)	$	(192.2	)

Reconciliation of Beginning and Ending Liability for Uncertain Tax Positions

A reconciliation of the beginning and ending amount of the consolidated liability for unrecognized income tax benefits during the year ended December 31, 2019 and 2018 is shown in the following table.



	Year Ended December 31,
(Millions of dollars)	2019			2018
Balance at January 1	$	0.7		$	4.4
Additions for tax positions related to prior years	0.5			—
Additions for tax positions related to current year	—			0.2
Settlements with taxing authorities	(0.6		)	(3.9		)
Expiration of statutes of limitation	—			—
Balance at December 31	$	0.6		$	0.7

Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2019

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Amounts Recognized in Financial Statements with Respect to Share-Based Plans

Amounts recognized in the financial statements by the Company with respect to all share-based plans are shown in the following table.



	Years Ended December 31,
(Millions of dollars)	2019		2018		2017
Compensation charged against income before income tax benefit	$	10.5	$	9.2	$	7.5
Related income tax benefit recognized in income	$	2.2	$	1.9	$	2.6

Summary of Changes in Stock Options Outstanding

Changes in options outstanding for Company employees during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Options	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (Millions of Dollars)
Outstanding at December 31, 2018	310,362		65.71
Granted	99,400		76.15
Exercised	(12,662	)	56.63
Forfeited	(4,800	)	76.15
Outstanding at December 31, 2019	392,300		$	68.52	4.3	$	19.0

Exercisable at December 31, 2019	174,300		$	64.00	3.0	$	9.2

Summary of Additional Stock Option Information

Additional information about stock options outstanding at December 31, 2019 is shown below:



	Options Outstanding		Options Exercisable
Range of Exercise Prices per Option	No. of Options	Avg. Life Remaining in Years	No. of Options	Avg. Life Remaining in Years
$39.46 to $49.99	3,900	1.1	3,900	1.1
$50.00 to $59.99	71,000	3.1	71,000	3.1
$60.00 to $69.99	90,550	4.1	43,550	4.1
$70.00 to $79.99	226,850	4.8	55,850	2.1
	392,300	4.3	174,300	3.0

MUSA 2013 Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Valuation Assumptions

Following are the assumptions used by the Company to value the original awards:



	Years Ended December 31,
	2019			2018			2017
Fair value per option grant	$	20.48		$	17.32		$	15.45
Assumptions
Dividend yield	—			—			—
Expected volatility	26.8		%	27.0		%	26		%
Risk-free interest rate	2.5		%	2.43		%	1.65		%
Expected life (years)	4.5			3.9			4.2
Stock price at valuation date	$	76.15		$	71.00		$	65.75

Restricted Stock Units | MUSA 2013 Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Restricted Stock Unit Activity

Changes in restricted stock units outstanding for Company employees during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Employee RSUs	Number of units		Weighted Average Grant Date Fair Value		Total Fair Value (Millions of Dollars)
Outstanding at December 31, 2018	193,478		$	64.02
Granted	74,118		$	80.85
Vested and issued	(54,313	)	$	60.41	$	4.2
Forfeited	(14,368	)	$	73.63
Outstanding at December 31, 2019	198,915		$	70.58	$	23.3

Restricted Stock Units | 2013 Stock Plan For Non-Employee Directors

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Restricted Stock Unit Activity

Changes in restricted stock units outstanding for Company non-employee directors during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Director RSU's	Number of Units		Weighted Average Grant Date Fair Value		Total Fair Value (Millions of Dollars)
Outstanding at December 31, 2018	41,017		$	64.27
Granted	13,086		$	76.63
Vested and issued	(20,496	)	$	61.65	$	1.6
Forfeited	—
Outstanding at December 31, 2019	33,607		$	70.68	$	3.9

Performance Units | MUSA 2013 Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Restricted Stock Unit Activity

Changes in performance-based restricted stock units outstanding for Company employees during the period from December 31, 2018 to December 31, 2019 are presented in the following table:



Employee PSU's	Number of Units		Weighted Average Grant Date Fair Value		Total Fair Value (Millions of Dollars)
Outstanding at December 31, 2018	124,412		$	76.58
Granted	81,513		$	88.40
Vested and issued	(72,125	)	$	73.55	$	5.5
Forfeited	(2,600	)	$	88.40
Outstanding at December 31, 2019	131,200		$	82.98	$	15.4

Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Reconciliation of Basic and Diluted Earnings Per Share Computations

The following table provides a reconciliation of basic and diluted earnings per share computations for the years ended December 31, 2019, 2018 and 2017 (in millions, except per share amounts):



	Years ended December 31,
(Millions of dollars except per share amounts)	2019		2018		2017
Earnings per common share:
Net income per share - basic
Net income attributable to common stockholders	$	154.8	$	213.6	$	245.3

Weighted average common shares outstanding (in thousands)	31,594		32,674		35,816
Earnings per common share	$	4.90	$	6.54	$	6.85

Earnings per common share - assuming dilution:
Net income per share - diluted
Net income attributable to common stockholders	$	154.8	$	213.6	$	245.3
Weighted average common shares outstanding (in thousands)	31,594		32,674		35,816
Common equivalent shares:
Share-based awards	264		309		340
Weighted average common shares outstanding - assuming dilution (in thousands)	31,858		32,983		36,156

Earnings per common share assuming dilution	$	4.86	$	6.48	$	6.78

Other Financial Information (Tables)

12 Months Ended

Dec. 31, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of Changes in Operating Working Capital

CHANGES IN WORKING CAPITAL -



(Millions of dollars)	2019			2018			2017
Accounts receivable	$	(33.4	)	$	86.6		$	(41.7	)
Inventories	(6.1		)	(39.0		)	(16.3		)
Prepaid expenses and other current assets	(3.3		)	11.4			(5.2		)
Accounts payable and accrued liabilities	(5.9		)	(56.7		)	26.9
Income taxes payable	—			—			(0.6		)
Net decrease (increase) in noncash operating working capital	$	(48.7	)	$	2.3		$	(36.9	)

Assets and Liabilities Measure at Fair Value (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Carrying Amounts and Estimated Fair Value of Financial Instruments

The following table presents the carrying amounts and estimated fair values of financial instruments held by the Company at December 31, 2019 and 2018. The fair value of a financial instrument is the amount at which the instrument could be exchanged in a current transaction between willing parties. The table excludes Cash and cash equivalents, Accounts receivable-trade, and Trade accounts payable and accrued liabilities, all of which had fair values approximating carrying amounts. The fair value of Current and Long-term debt was estimated based on rates offered to the Company at that time for debt of the same maturities. The Company has off-balance sheet exposures relating to certain financial guarantees and letters of credit. The fair value of these, which represents fees associated with obtaining the instruments, was nominal.



	December 31, 2019						December 31, 2018
	Carrying						Carrying
(Millions of dollars)	Amount			Fair Value			Amount			Fair Value
Financial liabilities
Current and long-term debt	$	(1,038.1	)	$	(1,069.4	)	$	(863.3	)	$	(866.7	)

Lease Accounting (Tables)

12 Months Ended

Dec. 31, 2019

Leases [Abstract]

Lessee, Lease

Leases are reflected in the following balance sheet accounts:



(Millions of dollars)	Classification	December 31, 2019		December 31, 2018
Assets
Operating (Right-of-use)	Other Assets	$	124.2	$	—
Finance	Property, plant, and equipment, at cost, less accumulated depreciation of $2.2 in 2019 and$1.8 in 2018	3.0		2.9
Total leased assets		$	127.2	$	2.9

Liabilities
Current
Operating	Trade accounts payable and accrued liabilities	$	6.8	$	—
Finance	Current maturities of long-term debt	1.2		1.2
Noncurrent
Operating	Deferred credits and other liabilities	118.5		—
Finance	Long-term debt, including capitalized lease obligations	1.2		1.1
Total lease liabilities		$	127.7	$	2.3

Lease, Cost

Lease Term and Discount Rate:



	Year Ended December 31,
	2019
Weighted average remaining lease term (years)
Finance leases	2.0
Operating leases	15.6
Weighted average discount rate
Finance leases	4.8	%
Operating leases	6.0	%

Lease Cost:



		Year Ended December 31,
(Millions of dollars)	Classification	2019
Operating lease cost	Station and other operating expenses	$	14.5
Finance lease cost
Amortization of leased assets	Depreciation & amortization expense	1.2
Interest on lease liabilities	Interest expense	0.1
Net lease costs		$	15.8

Cash flow information:



	Year Ended December 31,
(Millions of dollars)	2019
Cash paid for amounts included in the measurement of liabilities
Operating cash flows required by operating leases	$	13.8
Operating cash flows required by finance leases	$	0.1
Financing cash flows required by finance leases	$	1.4

Maturity of Operating Lease Liability

Maturity of Lease Liabilities:



(Millions of dollars)	Operating leases		Finance leases
2020	$	14.9	$	1.3
2021	14.3		0.9
2022	13.5		0.3
2023	13.0		—
2024	12.2		—
After 2024	148.9		—
Total lease payments	216.8		2.5
less: interest	91.5		0.1
Present value of lease liabilities	$	125.3	$	2.4

Maturity of Finance Lease Liabilities

Maturity of Lease Liabilities:



(Millions of dollars)	Operating leases		Finance leases
2020	$	14.9	$	1.3
2021	14.3		0.9
2022	13.5		0.3
2023	13.0		—
2024	12.2		—
After 2024	148.9		—
Total lease payments	216.8		2.5
less: interest	91.5		0.1
Present value of lease liabilities	$	125.3	$	2.4

Schedule of Future Minimum Lease Payments for Capital Leases

Future annual minimum lease payments and capital lease commitments as of December 31, 2018 were as follows:



(Millions of dollars)	Operating leases		Capital leases
2019	$	13.7	$	1.5
2020	13.3		1.1
2021	12.5		0.6
2022	11.7		0.1
2023	11.1		—
After 2023	122.6		—
Total lease payments	184.9		3.3
less: interest	—		0.2
Present value of minimum payments	$	184.9	$	3.1

Schedule of Future Minimum Rental Payments for Operating Leases

Future annual minimum lease payments and capital lease commitments as of December 31, 2018 were as follows:



(Millions of dollars)	Operating leases		Capital leases
2019	$	13.7	$	1.5
2020	13.3		1.1
2021	12.5		0.6
2022	11.7		0.1
2023	11.1		—
After 2023	122.6		—
Total lease payments	184.9		3.3
less: interest	—		0.2
Present value of minimum payments	$	184.9	$	3.1

Business Segments (Tables)

12 Months Ended

Dec. 31, 2019

Segment Reporting [Abstract]

Summary of Information by Business Segment



Segment Information				Corporate and
(Millions of dollars)	Marketing			Other Assets		Consolidated
Year ended December 31, 2019
Segment income (loss)	$	215.0		(60.2	)	$	154.8
Revenues from external customers	14,034.3			0.3		14,034.6
Interest income	—			3.2		3.2
Interest expense	(0.1		)	(54.8	)	(54.9		)
Loss on early debt extinguishment	—			(14.8	)	(14.8		)
Income tax expense (benefit)	66.3			(18.7	)	47.6
Significant noncash charges (credits)
Depreciation and amortization	138.9			13.3		152.2
Accretion of asset retirement obligations	2.1			—		2.1
Debt extinguishment costs	—			4.4		4.4
Deferred and noncurrent income taxes (benefits)	32.9			(9.2	)	23.7
Additions to property, plant and equipment	155.5			59.1		214.6
Total assets at year-end	$	2,304.7		382.5		$	2,687.2



Segment Information				Corporate and
(Millions of dollars)	Marketing			Other Assets		Consolidated
Year ended December 31, 2018
Segment income (loss)	$	214.2		(0.6	)	$	213.6
Revenues from external customers	14,362.3			0.6		14,362.9
Interest income	—			1.5		1.5
Interest expense	(0.1		)	(52.8	)	(52.9		)
Income tax expense (benefit)	69.5			(9.2	)	60.3
Significant noncash charges (credits)
Depreciation and amortization	124.5			9.5		134.0
Accretion of asset retirement obligations	2.0			—		2.0
Deferred and noncurrent income taxes (benefits)	39.0			(1.1	)	37.9
Additions to property, plant and equipment	169.2			24.6		193.8
Total assets at year-end	$	2,012.0		348.8		$	2,360.8



Segment Information				Corporate and
(Millions of dollars)	Marketing			Other Assets		Consolidated
Year ended December 31, 2017
Segment income (loss)	$	295.3		(50.0	)	$	245.3
Revenues from external customers	12,826.2			0.4		12,826.6
Interest income	—			1.3		1.3
Interest expense	(0.1		)	(46.6	)	(46.7		)
Income tax expense (benefit)	(2.9		)	(2.3	)	(5.2		)
Significant noncash charges (credits)
Depreciation and amortization	110.5			6.4		116.9
Accretion of asset retirement obligations	1.8			—		1.8
Deferred and noncurrent income taxes (benefits)	(61.3		)	10.9		(50.4		)
Additions to property, plant and equipment	234.0			39.7		273.7
Total assets at year-end	$	2,023.4		307.6		$	2,331.0

Guarantor Subsidiaries (Tables)

12 Months Ended

Dec. 31, 2019

Guarantor Subsidiaries [Abstract]

Consolidating Balance Sheet

CONSOLIDATING BALANCE SHEET



(Millions of dollars)	December 31, 2019
Assets	Parent Company			Issuer		Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Current assets
Cash and cash equivalents	$	—		$	279.4	$	0.9		$	—		$	—		$	280.3
Accounts receivable—trade, less allowance for doubtful accounts of $1.2 in 2019	—			173.0		(0.1		)	—			—			172.9
Inventories, at lower of cost or market	—			227.6		—			—			—			227.6
Prepaid expenses and other current assets	—			29.6		0.4			—			—			30.0
Total current assets	—			709.6		1.2			—			—			710.8
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019	—			1,799.1		8.2			—			—			1,807.3
Investments in subsidiaries	2,591.8			143.9		—			—			(2,735.7		)	—
Other assets	—			169.1		—			—			—			169.1
Total assets	$	2,591.8		$	2,821.7	$	9.4		$	—		$	(2,735.7	)	$	2,687.2
Liabilities and Stockholders' Equity
Current liabilities
Current maturities of long-term debt	$	—		$	38.8	$	—		$	—		$	—		$	38.8
Inter-company accounts payable	(0.1		)	196.1		(41.7		)	(154.3		)	—			—
Trade accounts payable and accrued liabilities	—			466.2		—			—			—			466.2
Total current liabilities	(0.1		)	701.1		(41.7		)	(154.3		)	—			505.0
Long-term debt, including capitalized lease obligations	—			999.3		—			—			—			999.3
Deferred income taxes	—			216.7		—			—			—			216.7
Asset retirement obligations	—			32.8		—			—			—			32.8
Deferred credits and other liabilities	—			130.4		—			—			—			130.4
Total liabilities	(0.1		)	2,080.3		(41.7		)	(154.3		)	—			1,884.2
Stockholders' Equity
Preferred Stock, par $0.01 (authorized 20,000,000 shares, none outstanding)	—			—		—			—			—			—
Common Stock, par $0.01 (authorized 200,000,000 shares, 46,767,164 shares issued at December 31, 2019)	0.5			—		0.1			—			(0.1		)	0.5
Treasury stock (16,307,048 shares held at December 31, 2019)	(1,099.8		)	—		—			—			—			(1,099.8		)
Additional paid in capital (APIC)	1,188.8			578.8		52.0			87.5			(1,368.4		)	538.7
Retained earnings	2,502.4			161.9		(1.0		)	66.8			(1,367.2		)	1,362.9
Accumulated other comprehensive income (AOCI)	—			0.7		—			—			—			0.7
Total stockholders' equity	2,591.9			741.4		51.1			154.3			(2,735.7		)	803.0
Total liabilities and stockholders' equity	$	2,591.8		$	2,821.7	$	9.4		$	—		$	(2,735.7	)	$	2,687.2

CONSOLIDATING BALANCE SHEET



(Millions of dollars)	December 31, 2018
Assets	Parent Company			Issuer		Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Current assets
Cash and cash equivalents	$	—		$	184.0	$	0.5		$	—		$	—		$	184.5
Accounts receivable—trade, less allowance for doubtful accounts of $1.1 in 2018	—			138.8		—			—			—			138.8
Inventories, at lower of cost or market	—			221.5		—			—			—			221.5
Prepaid expenses and other current assets	—			25.1		0.2			—			—			25.3
Total current assets	—			569.4		0.7			—			—			570.1
Property, plant and equipment, at cost less accumulated depreciation and amortization of $974.2 in 2018	—			1,745.9		2.3			—			—			1,748.2
Investments in subsidiaries	2,437.0			144.4		—			—			(2,581.4		)	—
Other assets	—			42.5		—			—			—			42.5
Total assets	$	2,437.0		$	2,502.2	$	3.0		$	—		$	(2,581.4	)	$	2,360.8
Liabilities and Stockholders' Equity
Current liabilities
Current maturities of long-term debt	$	—		$	21.2	$	—		$	—		$	—		$	21.2
Inter-company accounts payable	(0.1		)	203.0		(48.6		)	(154.3		)	—			—
Trade accounts payable and accrued liabilities	—			456.9		—			—			—			456.9
Total current liabilities	(0.1		)	681.1		(48.6		)	(154.3		)	—			478.1
Long-term debt, including capitalized lease obligations	—			842.1		—			—			—			842.1
Deferred income taxes	—			192.2		—			—			—			192.2
Asset retirement obligations	—			30.7		—			—			—			30.7
Deferred credits and other liabilities	—			10.4		—			—			—			10.4
Total liabilities	(0.1		)	1,756.5		(48.6		)	(154.3		)	—			1,553.5
Stockholders' Equity
Preferred Stock, par $0.01 (authorized 20,000,000 shares, none outstanding)	—			—		—			—			—			—
Common Stock, par $0.01 (authorized 200,000,000 shares, 46,767,164 shares issued at December 31, 2018)	0.5			—		0.1			—			(0.1		)	0.5
Treasury stock (14,505,681 shares held at December 31, 2018)	(940.3		)	—		—			—			—			(940.3		)
Additional paid in capital (APIC)	1,195.1			572.8		52.0			87.5			(1,368.4		)	539.0
Retained earnings	2,181.8			172.9		(0.5		)	66.8			(1,212.9		)	1,208.1
Accumulated other comprehensive income (AOCI)	—			—		—			—			—			—
Total stockholders' equity	2,437.1			745.7		51.6			154.3			(2,581.4		)	807.3
Total liabilities and stockholders' equity	$	2,437.0		$	2,502.2	$	3.0		$	—		$	(2,581.4	)	$	2,360.8

Consolidating Income Statement

CONSOLIDATING INCOME STATEMENT AND COMPREHENSIVE INCOME



(Millions of dollars)	Year ended December 31, 2019
Operating Revenues	Parent Company		Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Petroleum product sales	$	—	$	11,373.8		$	—		$	—	$	—		$	11,373.8
Merchandise sales	—		2,620.1			—			—		—			2,620.1
Other operating revenues	—		40.7			—			—		—			40.7
Total operating revenues	—		14,034.6			—			—		—			14,034.6
Operating expenses
Petroleum product cost of goods sold	—		10,707.4			—			—		—			10,707.4
Merchandise cost of goods sold	—		2,200.7			—			—		—			2,200.7
Station and other operating expenses	—		559.3			—			—		—			559.3
Depreciation and amortization	—		152.1			0.1			—		—			152.2
Selling, general and administrative	—		144.6			—			—		—			144.6
Accretion of asset retirement obligations	—		2.1			—			—		—			2.1
Total operating expenses	—		13,766.2			0.1			—		—			13,766.3
Net settlement proceeds	—		0.1			—			—		—			0.1
Gain (loss) on sale of assets	—		0.1			—			—		—			0.1
Income from operations	—		268.6			(0.1		)	—		—			268.5
Other income (expense)
Interest income	—		3.2			—			—		—			3.2
Interest expense	—		(54.9		)	—			—		—			(54.9		)
Loss on early debt extinguishment	—		(14.8		)	—			—		—			(14.8		)
Other nonoperating income/expense	165.8		(164.8		)	(0.6		)	—		—			0.4
Total other income (expense)	165.8		(231.3		)	(0.6		)	—		—			(66.1		)
Income before income taxes	165.8		37.3			(0.7		)	—		—			202.4
Income tax expense (benefit)	—		47.8			(0.2		)	—		—			47.6
Income (loss)	165.8		(10.5		)	(0.5		)	—		—			154.8
Equity earnings in affiliates, net of tax	154.8		(0.5		)	—			—		(154.3		)	—
Net income (loss)	$	320.6	$	(11.0	)	$	(0.5	)	$	—	$	(154.3	)	$	154.8
Other comprehensive income	—		0.7			—			—		—			0.7
Comprehensive income (loss)	$	320.6	$	(10.3	)	$	(0.5	)	$	—	$	(154.3	)	$	155.5

CONSOLIDATING INCOME STATEMENT AND COMPREHENSIVE INCOME



(Millions of dollars)	Year ended December 31, 2018
Operating Revenues	Parent Company		Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Petroleum product sales	$	—	$	11,858.4		$	—		$	—	$	—		$	11,858.4
Merchandise sales	—		2,423.0			—			—		—			2,423.0
Ethanol sales and other	—		81.5			—			—		—			81.5
Total operating revenues	—		14,362.9			—			—		—			14,362.9
Operating Expenses
Petroleum product cost of goods sold	—		11,251.1			—			—		—			11,251.1
Merchandise cost of goods sold	—		2,022.5			—			—		—			2,022.5
Station and other operating expenses	—		541.3			—			—		—			541.3
Depreciation and amortization	—		134.0			—			—		—			134.0
Selling, general and administrative	—		136.2			—			—		—			136.2
Accretion of asset retirement obligations	—		2.0			—			—		—			2.0
Total operating expenses	—		14,087.1			—			—		—			14,087.1
Net settlement proceeds			50.4											50.4
Gain (loss) on sale of assets	—		(1.1		)	—			—		—			(1.1		)
Income from operations	—		325.1			—			—		—			325.1
Other income (expense)
Interest income	—		1.5			—			—		—			1.5
Interest expense	—		(52.9		)	—			—		—			(52.9		)
Other nonoperating income	973.7		(972.9		)	(0.6		)	—		—			0.2
Total other income (expense)	973.7		(1,024.3		)	(0.6		)	—		—			(51.2		)
Income before income taxes	973.7		(699.2		)	(0.6		)	—		—			273.9
Income tax expense (benefit)	—		60.4			(0.1		)	—		—			60.3
Income	973.7		(759.6		)	(0.5		)	—		—			213.6
Equity earnings in affiliates, net of tax	213.6		(0.5		)	—			—		(213.1		)	—
Net income (loss)	$	1,187.3	$	(760.1	)	$	(0.5	)	$	—	$	(213.1	)	$	213.6
Other comprehensive income	—		—			—			—		—			—
Comprehensive income (loss)	$	1,187.3	$	(760.1	)	$	(0.5	)	$	—	$	(213.1	)	$	213.6

CONSOLIDATING INCOME STATEMENT AND COMPREHENSIVE INCOME



(Millions of dollars)	Year ended December 31, 2017
Operating Revenues	Parent Company		Issuer			Guarantor Subsidiaries		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Petroleum product sales	$	—	$	10,287.9		$	—	$	—	$	—		$	10,287.9
Merchandise sales	—		2,372.7			—		—		—			2,372.7
Ethanol sales and other	—		166.0			—		—		—			166.0
Total operating revenues	—		12,826.6			—		—		—			12,826.6
Operating expenses
Petroleum product cost of goods sold	—		9,773.2			—		—		—			9,773.2
Merchandise cost of goods sold	—		1,991.4			—		—		—			1,991.4
Station and other operating expenses	—		514.9			—		—		—			514.9
Depreciation and amortization	—		116.9			—		—		—			116.9
Selling, general and administrative	—		141.2			—		—		—			141.2
Accretion of asset retirement obligations	—		1.8			—		—		—			1.8
Total operating expenses	—		12,539.4			—		—		—			12,539.4
Gain (loss) on sale of assets	—		(3.9		)	—		—		—			(3.9		)
Income from operations	—		283.3			—		—		—			283.3
Other income (expense)
Interest income	—		1.3			—		—		—			1.3
Interest expense	—		(46.7		)	—		—		—			(46.7		)
Other nonoperating income	—		2.2			—		—		—			2.2
Total other income (expense)	—		(43.2		)	—		—		—			(43.2		)
Income before income taxes	—		240.1			—		—		—			240.1
Income tax expense (benefit)	—		(5.2		)	—		—		—			(5.2		)
Income	—		245.3			—		—		—			245.3
Equity earnings in affiliates, net of tax	245.3		—			—		—		(245.3		)	—
Net income (loss)	$	245.3	$	245.3		$	—	$	—	$	(245.3	)	$	245.3
Other comprehensive income	—		—			—		—		—			—
Comprehensive income (loss)	$	245.3	$	245.3		$	—	$	—	$	(245.3	)	$	245.3

Consolidating Statement of Cash Flow

CONSOLIDATING STATEMENT OF CASH FLOWS



(Millions of dollars)	Year ended December 31, 2019
Operating Activities	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Net income (loss)	$	320.6		$	(11.0	)	$	(0.5	)	$	—	$	(154.3	)	$	154.8
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	—			152.1			0.1			—		—			152.2
Deferred and noncurrent income tax charges (benefits)	—			23.7			—			—		—			23.7
Accretion of asset retirement obligations	—			2.1			—			—		—			2.1
(Gain) loss from sale of assets	—			(0.1		)	—			—		—			(0.1		)
Net decrease (increase) in noncash operating working capital	—			(48.6		)	(0.1		)	—		—			(48.7		)
Equity in earnings	(154.8		)	0.5			—			—		154.3			—
Loss on early debt extinguishment	—			14.8			—			—		—			14.8
Other operating activities - net	—			14.5			—			—		—			14.5
Net cash provided by (required by) operating activities	165.8			148.0			(0.5		)	—		—			313.3
Investing Activities
Property additions	—			(198.8		)	(6.0		)	—		—			(204.8		)
Proceeds from sale of assets	—			2.5			—			—		—			2.5
Other investing activities - net	—			(0.8		)	—			—		—			(0.8		)
Net cash provided by (required by) investing activities	—			(197.1		)	(6.0		)	—		—			(203.1		)
Financing Activities
Purchase of treasury stock	(165.8		)	—			—			—		—			(165.8		)
Repayments of debt	—			(573.4		)	—			—		—			(573.4		)
Borrowings of debt	—			743.8			—			—		—			743.8
Early debt extinguishment costs	—			(10.4		)	—			—		—			(10.4		)
Debt issuance costs	—			(4.1		)	—			—		—			(4.1		)
Amounts related to share-based compensation	—			(4.5		)	—			—		—			(4.5		)
Net distributions to parent	—			(6.9		)	6.9			—		—			—
Net cash provided by (required by) financing activities	(165.8		)	144.5			6.9			—		—			(14.4		)
Net change in cash, cash equivalents, and restricted cash	—			95.4			0.4			—		—			95.8
Cash, cash equivalents, and restricted cash at January 1	—			184.0			0.5			—		—			184.5
Cash, cash equivalents, and restricted cash at December 31	$	—		$	279.4		$	0.9		$	—	$	—		$	280.3

Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and Cash equivalents at beginning of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5
Restricted cash at beginning of period	—			—			—			—		—			—
Cash, cash equivalents, and restricted cash at beginning of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5

Cash and cash equivalents at end of period	$	—		$	279.4		$	0.9		$	—	$	—		$	280.3
Restricted cash at end of period	—			—			—			—		—			—
Cash, cash equivalents, and restricted cash at end of period	$	—		$	279.4		$	0.9		$	—	$	—		$	280.3

CONSOLIDATING STATEMENT OF CASH FLOWS



(Millions of dollars)	Year ended December 31, 2018
Operating Activities	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Net income (loss)	$	1,187.3		$	(760.1	)	$	(0.5	)	$	—	$	(213.1	)	$	213.6
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	—			134.0			—			—		—			134.0
Deferred and noncurrent income tax charges (credits)	—			37.9			—			—		—			37.9
Accretion of asset retirement obligations	—			2.0			—			—		—			2.0
(Gains) loss from sale of assets	—			1.1			—			—		—			1.1
Net decrease (increase) in noncash operating working capital	—			2.4			(0.1		)	—		—			2.3
Equity in earnings	(213.6		)	0.5			—			—		213.1			—
Other operating activities - net	—			7.8			—			—		—			7.8
Net cash provided by (required by) operating activities	973.7			(574.4		)	(0.6		)	—		—			398.7
Investing Activities
Property additions	—			(203.1		)	(1.2		)	—		—			(204.3		)
Proceeds from sale of assets	—			1.2			—			—		—			1.2
Other investing activities - net	—			(6.0		)	—			—		—			(6.0		)
Net cash provided by (required by) investing activities	—			(207.9		)	(1.2		)	—		—			(209.1		)
Financing Activities
Purchase of treasury stock	(144.4		)	—			—			—		—			(144.4		)
Repayments of debt	—			(21.3		)	—			—		—			(21.3		)
Borrowings of debt	—			—			—			—		—			—
Debt issuance costs	—			—			—			—		—			—
Amounts related to share-based compensation	—			(9.4		)	—			—		—			(9.4		)
Net distributions to parent	(829.3		)	827.1			2.2			—		—			—
Net cash provided by (required by) financing activities	(973.7		)	796.4			2.2			—		—			(175.1		)
Net change in cash, cash equivalents, and restricted cash	—			14.1			0.4			—		—			14.5
Cash, cash equivalents, and restricted cash at January 1	—			169.9			0.1			—		—			170.0
Cash, cash equivalents, and restricted cash at December 31	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5

Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents at beginning of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0
Restricted cash at beginning of period	—			—			—			—		—			—
Cash, cash equivalents and restricted cash at beginning of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0

Cash and cash equivalents at end of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5
Restricted cash at end of period	—			—			—			—		—			—
Cash, cash equivalents and restricted cash at end of period	$	—		$	184.0		$	0.5		$	—	$	—		$	184.5

CONSOLIDATING STATEMENT OF CASH FLOWS



(Millions of dollars)	Year ended December 31, 2017
Operating Activities	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Net income (loss)	$	245.3		$	245.3		$	—		$	—	$	(245.3	)	$	245.3
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	—			116.9			—			—		—			116.9
Deferred and noncurrent income tax charges (credits)	—			(50.4		)	—			—		—			(50.4		)
Accretion of asset retirement obligations	—			1.8			—			—		—			1.8
(Gains) loss from sale of assets	—			3.9			—			—		—			3.9
Net decrease (increase) in noncash operating working capital	—			(36.9		)	—			—		—			(36.9		)
Equity in earnings	(245.3		)	—			—			—		245.3			—
Other operating activities - net	—			3.0			—			—		—			3.0
Net cash provided by (required by) operating activities	—			283.6			—			—		—			283.6
Investing Activities
Property additions	—			(257.1		)	(1.2		)	—		—			(258.3		)
Proceeds from sale of assets	—			0.9			—			—		—			0.9
Other investing activities - net	—			(4.7		)	—			—		—			(4.7		)
Net cash provided by (required by) investing activities	—			(260.9		)	(1.2		)	—		—			(262.1		)
Financing Activities
Purchase of treasury stock	(206.0		)	—			—			—		—			(206.0		)
Repayments of debt	—			(131.4		)	—			—		—			(131.4		)
Borrowings of debt	—			338.8			—			—		—			338.8
Debt issuance costs	—			(1.1		)	—			—		—			(1.1		)
Amounts related to share-based compensation	—			(5.6		)	—			—		—			(5.6		)
Net distributions to parent	206.0			(207.3		)	1.3			—		—			—
Net cash provided by (required by) financing activities	—			(6.6		)	1.3			—		—			(5.3		)
Net change in cash, cash equivalents, and restricted cash	—			16.1			0.1			—		—			16.2
Cash, cash equivalents and restricted cash at January 1	—			153.8			—			—		—			153.8
Cash, cash equivalents and restricted cash at December 31	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0

Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents at beginning of period	$	—		$	153.8		$	—		$	—	$	—		$	153.8
Restricted cash at beginning of period	—			—			—			—		—			—
Cash, cash equivalents and restricted cash at beginning of period	$	—		$	153.8		$	—		$	—	$	—		$	153.8

Cash and cash equivalents at end of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0
Restricted cash at end of period	—			—			—			—		—			$	—
Cash, cash equivalents and restricted cash at end of period	$	—		$	169.9		$	0.1		$	—	$	—		$	170.0

Consolidating Statement of Changes in Equity

CONSOLIDATING STATEMENT OF CHANGES IN EQUITY



(Millions of dollars)	Year ended December 31, 2019
Statement of Stockholders' Equity	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Common Stock
Balance as of December 31, 2018	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Issuance of common stock	—			—			—			—		—			—
Balance as of December 31, 2019	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Treasury Stock
Balance as of December 31, 2018	$	(940.3	)	$	—		$	—		$	—	$	—		$	(940.3	)
Issuance of treasury stock	6.3			—			—			—		—			6.3
Purchase of treasury stock	(165.8		)	—			—			—		—			(165.8		)
Balance as of December 31, 2019	$	(1,099.8	)	$	—		$	—		$	—	$	—		$	(1,099.8	)
APIC
Balance as of December 31, 2018	$	1,195.1		$	572.8		$	52.0		$	87.5	$	(1,368.4	)	$	539.0
Issuance of treasury stock	(6.3		)	—			—			—		—			(6.3		)
Amounts related to share-based compensation	—			(4.5		)	—			—		—			(4.5		)
Share-based compensation expense	—			10.5			—			—		—			10.5
Balance as of December 31, 2019	$	1,188.8		$	578.8		$	52.0		$	87.5	$	(1,368.4	)	$	538.7
Retained Earnings
Balance as of December 31, 2018	$	2,181.8		$	172.9		$	(0.5	)	$	66.8	$	(1,212.9	)	$	1,208.1
Net income	320.6			(11.0		)	(0.5		)	—		(154.3		)	154.8
Balance as of December 31, 2019	$	2,502.4		$	161.9		$	(1.0	)	$	66.8	$	(1,367.2	)	$	1,362.9
AOCI
Balance as of December 31, 2018	$	—		$	—		$	—		$	—	$	—		$	—
Other comprehensive income	—			0.7			—			—		—			0.7
Balance as of December 31, 2019	$	—		$	0.7		$	—		$	—	$	—		$	0.7

CONSOLIDATING STATEMENTS OF CHANGES IN EQUITY



(Millions of dollars)	Year ended December 31, 2018
Statement of Stockholders' Equity	Parent Company			Issuer			Guarantor Subsidiaries			Non-Guarantor Subsidiaries		Eliminations			Consolidated
Common Stock
Balance as of December 31, 2017	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Issuance of common stock	—			—			—			—		—			—
Balance as of December 31, 2018	$	0.5		$	—		$	0.1		$	—	$	(0.1	)	$	0.5
Treasury Stock
Balance as of December 31, 2017	$	(806.5	)	$	—		$	—		$	—	$	—		$	(806.5	)
Issuance of treasury stock	10.6			—			—			—		—			10.6
Purchase of treasury stock	(144.4		)	—			—			—		—			(144.4		)
Balance as of December 31, 2018	$	(940.3	)	$	—		$	—		$	—	$	—		$	(940.3	)
APIC
Balance as of December 31, 2017	$	1,205.7		$	573.1		$	52.0		$	87.5	$	(1,368.4	)	$	549.9
Issuance of treasury stock	(10.6		)	—			—			—		—			(10.6		)
Amounts related to share-based compensation	—			(9.4		)	—			—		—			(9.4		)
Share-based compensation expense	—			9.1			—			—		—			9.1
Balance as of December 31, 2018	$	1,195.1		$	572.8		$	52.0		$	87.5	$	(1,368.4	)	$	539.0
Retained Earnings
Balance as of December 31, 2017	$	994.5		$	933.0		$	—		$	66.8	$	(999.8	)	$	994.5
Net income	1,187.3			(760.1		)	(0.5		)	—		(213.1		)	213.6
Balance as of December 31, 2018	$	2,181.8		$	172.9		$	(0.5	)	$	66.8	$	(1,212.9	)	$	1,208.1
AOCI
Balance as of December 31, 2017	$	—		$	—		$	—		$	—	$	—		$	—
Other comprehensive income	—			—			—			—		—			—
Balance as of December 31, 2018	$	—		$	—		$	—		$	—	$	—		$	—

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY



(Millions of dollars)	Year ended December 31, 2017
Statement of Stockholders' Equity	Parent Company			Issuer			Guarantor Subsidiaries		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Common Stock
Balance as of December 31, 2016	$	0.5		$	—		$	0.1	$	—	$	(0.1	)	$	0.5
Issuance of common stock	—			—			—		—		—			—
Balance as of December 31, 2017	$	0.5		$	—		$	0.1	$	—	$	(0.1	)	$	0.5
Treasury Stock
Balance as of December 31, 2016	$	(608.0	)	$	—		$	—	$	—	$	—		$	(608.0	)
Issuance of treasury stock	7.5			—			—		—		—			7.5
Purchase of treasury stock	(206.0		)	—			—		—		—			(206.0		)
Balance as of December 31, 2017	$	(806.5	)	$	—		$	—	$	—	$	—		$	(806.5	)
APIC
Balance as of December 31, 2016	$	1,213.1		$	571.1		$	52.0	$	87.5	$	(1,368.4	)	$	555.3
Issuance of treasury stock	(7.4		)	—			—		—		—			(7.4		)
Amounts related to share-based compensation	—			(5.6		)	—		—		—			(5.6		)
Share-based compensation expense	—			7.6			—		—		—			7.6
Balance as of December 31, 2017	$	1,205.7		$	573.1		$	52.0	$	87.5	$	(1,368.4	)	$	549.9
Retained Earnings
Balance as of December 31, 2016	$	749.2		$	687.7		$	—	$	66.8	$	(754.5	)	$	749.2
Net income	245.3			245.3			—		—		(245.3		)	245.3
Balance as of December 31, 2017	$	994.5		$	933.0		$	—	$	66.8	$	(999.8	)	$	994.5
AOCI
Balance as of December 31, 2016	$	—		$	—		$	—	$	—	$	—		$	—
Other comprehensive income	—			—			—		—		—			—
Balance as of December 31, 2017	$	—		$	—		$	—	$	—	$	—		$	—

Supplemental Quarterly Information (Tables)

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information



	First		Second		Third		Fourth
(Millions of dollars except per share amounts)	Quarter		Quarter		Quarter		Quarter		Year
Year Ended December 31, 2019
Sales and other operating revenues	$	3,116.4	$	3,800.4	$	3,657.6	$	3,460.2	$	14,034.6
Income (loss) from continuing operations before income taxes	$	5.9	$	43.3	$	91.3	$	61.9	$	202.4
Income (loss) from continuing operations	$	5.3	$	32.7	$	69.2	$	47.6	$	154.8
Net income (loss)	$	5.3	$	32.7	$	69.2	$	47.6	$	154.8
Income (loss) from continuing operations (per Common share)
Basic	$	0.16	$	1.02	$	2.20	$	1.56	$	4.90
Diluted	$	0.16	$	1.01	$	2.18	$	1.54	$	4.86
Net income (loss) (per Common share)
Basic	$	0.16	$	1.02	$	2.20	$	1.56	$	4.90
Diluted	$	0.16	$	1.01	$	2.18	$	1.54	$	4.86

Year Ended December 31, 2018
Sales and other operating revenues	$	3,244.2	$	3,829.0	$	3,788	$	3,501.7	$	14,362.9
Income (loss) from continuing operations before income taxes	$	47.3	$	69.1	$	57.0	$	100.5	$	273.9
Income (loss) from continuing operations	$	39.3	$	51.8	$	45.0	$	77.5	$	213.6
Net income (loss)	$	39.3	$	51.8	$	45.0	$	77.5	$	213.6
Income (loss) from continuing operations (per Common share)
Basic	$	1.17	$	1.59	$	1.40	$	2.40	$	6.54
Diluted	$	1.16	$	1.58	$	1.38	$	2.38	$	6.48
Net income (loss) (per Common share)
Basic	$	1.17	$	1.59	$	1.40	$	2.40	$	6.54
Diluted	$	1.16	$	1.58	$	1.38	$	2.38	$	6.48

Description of Business and Basis of Presentation (Details)	Aug. 31, 2013	Aug. 30, 2013	Dec. 31, 2019 state store
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Percentage of shares of stock distributed		100.00%
Ownership interest after transaction (percent)	0.00%
Number of states in which entity operates \| state			26
Number of stores \| store			1,489

Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Excise taxes	$ 1,933.3	$ 1,838.9	$ 1,973.1
Interest costs capitalized	$ 1.4	$ 2.2	$ 3.8
LKE transaction, required term to facilitate forward agreement before proceeds are reclassified as available cash (in days)	180 days
Pipeline and terminal facilities \| Minimum
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	16 years
Pipeline and terminal facilities \| Maximum
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	25 years
Marketing Facilities \| Minimum
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	3 years
Marketing Facilities \| Maximum
Property, Plant and Equipment [Line Items]
Depreciable life (in years)	50 years
Nonqualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Restricted Stock And Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years

Revenues (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 3,460.2	$ 3,657.6	$ 3,800.4	$ 3,116.4	$ 3,501.7	$ 3,788.0	$ 3,829.0	$ 3,244.2	$ 14,034.6	$ 14,362.9	$ 12,826.6
Merchandise sales
Disaggregation of Revenue [Line Items]
Revenue									2,620.1	2,423.0	2,372.7
Operating Segment
Disaggregation of Revenue [Line Items]
Revenue									14,034.3	75.2	12,826.2
Operating Segment \| Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Revenue									10,184.0	10,459.2	9,041.5
Operating Segment \| Petroleum product sales (at wholesale)
Disaggregation of Revenue [Line Items]
Revenue									1,189.8	1,399.2	1,246.4
Operating Segment \| Total petroleum product sales
Disaggregation of Revenue [Line Items]
Revenue									11,373.8	11,858.4	10,287.9
Operating Segment \| Merchandise sales
Disaggregation of Revenue [Line Items]
Revenue									2,620.1	2,423.0	2,372.6
Operating Segment \| Renewable Identification Numbers (RINs) sales
Disaggregation of Revenue [Line Items]
Revenue									34.8		160.3
Operating Segment \| Other
Disaggregation of Revenue [Line Items]
Revenue									5.6		5.4
Operating Segment \| Marketing
Disaggregation of Revenue [Line Items]
Revenue										14,362.3
Operating Segment \| Marketing \| Other
Disaggregation of Revenue [Line Items]
Revenue										5.7
Corporate and Other Assets
Disaggregation of Revenue [Line Items]
Revenue									$ 0.3	$ 0.6	$ 0.4

Revenues (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Revenues (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 3,460,200	$ 3,657,600	$ 3,800,400	$ 3,116,400	$ 3,501,700	$ 3,788,000	$ 3,829,000	$ 3,244,200	$ 14,034,600	$ 14,362,900	$ 12,826,600
Earned rewards, expiration period									90 days
Trade accounts receivable	172,900				138,800				$ 172,900	138,800
Receivables related to contracts with customers
Disaggregation of Revenue [Line Items]
Trade accounts receivable	$ 96,000				$ 79,400				$ 96,000	79,400
Petroleum product sales, rack sales
Disaggregation of Revenue [Line Items]
Collection period									10 days
Renewable Identification Numbers (RINs) sales
Disaggregation of Revenue [Line Items]
Collection period									5 days
Minimum \| Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Collection period									2 days
Maximum \| Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Collection period									7 days
Difference between Revenue Guidance in Effect before and after Topic 606 \| Petroleum product sales (at retail)
Disaggregation of Revenue [Line Items]
Revenue									$ 26,300	25,400
Difference between Revenue Guidance in Effect before and after Topic 606 \| Petroleum product sales (at wholesale)
Disaggregation of Revenue [Line Items]
Revenue									165,600	171,200
Difference between Revenue Guidance in Effect before and after Topic 606 \| Petroleum product sales
Disaggregation of Revenue [Line Items]
Revenue									$ 191,900	$ 196,500

Inventories (Summary Of Inventory) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Finished products - FIFO basis	$ 259,200	$ 219,400
Less LIFO reserve - finished products	(160,800)	(115,500)
Finished products - LIFO basis	98,400	103,900
Store merchandise for resale	123,000	107,200
Materials and supplies	6,200	10,400
Total inventories	227,600	221,500
LIFO carrying reserve	$ 160,800	$ 115,500

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Cost	$ 2,886,500	$ 2,722,400
Net	1,807,300	1,748,200
Depreciation expense	151,200	132,500	$ 115,000
Land
Property, Plant and Equipment [Line Items]
Cost	598,600	591,900
Net	598,600	591,900
Pipeline and terminal facilities
Property, Plant and Equipment [Line Items]
Cost	77,500	73,100
Net	43,700	41,600
Retail gasoline stations
Property, Plant and Equipment [Line Items]
Cost	2,034,400	1,890,600
Net	1,073,600	1,018,500
Buildings
Property, Plant and Equipment [Line Items]
Cost	60,500	55,000
Net	44,900	41,800
Other
Property, Plant and Equipment [Line Items]
Cost	115,500	111,800
Net	$ 46,500	$ 54,400
Minimum \| Pipeline and terminal facilities
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	16 years
Minimum \| Retail gasoline stations
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	3 years
Minimum \| Buildings
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	20 years
Minimum \| Other
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	3 years
Maximum \| Pipeline and terminal facilities
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	25 years
Maximum \| Retail gasoline stations
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	50 years
Maximum \| Buildings
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	45 years
Maximum \| Other
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	20 years

Accounts Payable And Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Trade accounts payable	$ 280,800	$ 274,900
Excise taxes/withholdings payable	86,200	89,700
Accrued insurance obligations	24,400	21,800
Accrued taxes other than income	25,600	26,600
Other	49,200	43,900
Accounts payable and accrued liabilities	$ 466,200	$ 456,900

Long-Term Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 13, 2019	Dec. 31, 2018	Apr. 25, 2017
Debt Instrument [Line Items]
Capitalized lease obligations, vehicles, due through 2022	$ 2,400
Capitalized lease obligations, vehicles, due through 2022			$ 2,300
Unamortized debt issuance costs	(5,500)		(3,800)
Total long-term debt	1,038,100		863,300
Less current maturities	38,800		21,200
Total long-term debt, net of current	999,300		842,100
Senior Notes \| 6.00% senior notes due 2023 (net of unamortized discount of $4.1 at 2018)
Debt Instrument [Line Items]
Long-term debt	$ 0		495,900
Unamortized discount			4,100
Interest rate (percent)	6.00%	6.00%
Senior Notes \| 5.625% senior notes due 2027 (net of unamortized discount of $2.7 at 2019 and $3.1 at 2018)
Debt Instrument [Line Items]
Long-term debt	$ 297,300		296,900
Unamortized discount	$ 2,700		3,100
Interest rate (percent)	5.625%			5.625%
Senior Notes \| 4.75 % senior notes due 2029 (net of unamortized discount of $6.1 at 2019)
Debt Instrument [Line Items]
Long-term debt	$ 493,900		0
Unamortized discount	$ 6,100
Interest rate (percent)	4.75%	4.75%
Secured Debt \| Term loan due 2020 (effective interest rate of 5.0% at 2018 ) \| Term Loan
Debt Instrument [Line Items]
Long-term debt	$ 0		$ 72,000
Effective interest rate			5.00%
Secured Debt \| Term loan due 2023 (effective interest rate of 4.3% at 2019) \| Term Loan
Debt Instrument [Line Items]
Long-term debt	$ 250,000		$ 0
Effective interest rate			4.30%

Long-Term Debt (Narrative) (Details) - USD ($)				12 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Apr. 01, 2020	Sep. 13, 2019	Aug. 27, 2019	Dec. 31, 2019	Aug. 31, 2019	Apr. 25, 2017
Debt Instrument [Line Items]
Fixed charge coverage ratio				0.93
Fixed charge coverage ratio threshold, percentage of aggregate facility commitments and borrowing base				17.50%
Fixed charge coverage ratio threshold, amount of aggregate facility commitments and borrowing base				$ 70,000,000
Secured debt to EBITDA ratio				0.58
Shortfall of net income and retained earnings				$ 30,600,000
Minimum
Debt Instrument [Line Items]
Fixed charge coverage ratio				1.0
Period for fixed charge coverage ratio threshold (in days)				3 days
Dividend restriction threshold as amount of availability				$ 100,000,000
Dividend restriction threshold as a percentage of revolving commitments and borrowing base				25.00%
Maximum
Debt Instrument [Line Items]
Secured debt to EBITDA ratio				4.5
Dividend restriction threshold as a percentage of revolving commitments and borrowing base with consideration of fixed charge coverage ratio				40.00%
Federal Funds Rate
Debt Instrument [Line Items]
Spread over variable rate (percent)				0.50%
LIBOR
Debt Instrument [Line Items]
Spread over variable rate (percent)				1.00%
Cash
Debt Instrument [Line Items]
Percentage of asset available to borrow against				100.00%
Credit Card Receivables
Debt Instrument [Line Items]
Percentage of asset available to borrow against				90.00%
Investment Grade Accounts
Debt Instrument [Line Items]
Percentage of asset available to borrow against				90.00%
Other Accounts
Debt Instrument [Line Items]
Percentage of asset available to borrow against				85.00%
Midstream Refined Products Inventory
Debt Instrument [Line Items]
Percentage of asset available to borrow against				80.00%
Refined Retail Products Inventory
Debt Instrument [Line Items]
Percentage of asset available to borrow against				75.00%
Retail Merchandise Inventory
Debt Instrument [Line Items]
Percentage of asset available to borrow against				70.00%
Percentage of net orderly liquidation value available to borrow against				85.00%
Secured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					$ 325,000,000
Secured Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Spread over variable rate (percent)				1.50%
Secured Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Spread over variable rate (percent)				2.00%
Secured Debt \| Alternative Base Rate \| Minimum
Debt Instrument [Line Items]
Spread over variable rate (percent)				0.50%
Secured Debt \| Alternative Base Rate \| Maximum
Debt Instrument [Line Items]
Spread over variable rate (percent)				1.00%
Term Loan
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					200,000,000
Proceeds from lines of credit			$ 200,000,000
Repayments of long-term debt			$ 57,000,000
Additional term loan				$ 50,000,000
Outstanding balance				$ 250,000,000
Term Loan \| LIBOR \| Minimum
Debt Instrument [Line Items]
Spread over variable rate (percent)				2.50%
Term Loan \| LIBOR \| Maximum
Debt Instrument [Line Items]
Spread over variable rate (percent)				2.75%
Term Loan \| Alternative Base Rate \| Minimum
Debt Instrument [Line Items]
Spread over variable rate (percent)				1.50%
Term Loan \| Alternative Base Rate \| Maximum
Debt Instrument [Line Items]
Spread over variable rate (percent)				1.75%
ABL Facility
Debt Instrument [Line Items]
Additional term loan				$ 100,000,000
Outstanding under facility				$ 0
Additional Term Loan Available Until December 2019 [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					50,000,000
Incremental Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					150,000,000
Letter Of Credit
Debt Instrument [Line Items]
Line of credit facility, sublimit					$ 100,000,000
Senior Notes \| 5.625% senior notes due 2027
Debt Instrument [Line Items]
Senior notes						$ 300,000,000
Interest rate (percent)				5.625%		5.625%
Senior Notes \| 6.00% senior notes due 2023
Debt Instrument [Line Items]
Senior notes		$ 500,000,000
Interest rate (percent)		6.00%		6.00%
Repayments of long-term debt		$ 514,500,000
Senior Notes \| Senior Notes 4.75 Percent Due 2029
Debt Instrument [Line Items]
Senior notes		$ 500,000,000
Interest rate (percent)		4.75%		4.75%
Forecast \| Term Loan
Debt Instrument [Line Items]
Principal payment period	$ 12,500,000

Asset Retirement Obligations (ARO) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Asset Retirement Obligation Roll Forward
Balance at beginning of period	$ 30.7	$ 28.2
Accretion expense	2.1	2.0	$ 1.8
Settlement of liabilities	(0.4)	(0.3)
Liabilities incurred	0.4	0.8
Balance at end of period	$ 32.8	$ 30.7	$ 28.2

Income Taxes (Schedule Of Components Of Income From Continuing Operations Before Income Taxes And Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ 61.9	$ 91.3	$ 43.3	$ 5.9	$ 100.5	$ 57.0	$ 69.1	$ 47.3	$ 202.4	$ 273.9	$ 240.1
Income tax expense (benefit)
Federal - Current									15.6	18.4	39.2
Federal - Deferred									21.7	31.0	(50.7)
State - Current and deferred									10.3	10.9	6.3
Total									$ 47.6	$ 60.3	$ (5.2)

Income Taxes (Schedule Of Reconciliation Of Income Taxes To Statutory Rate) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax expense based on the U.S. statutory tax rate		$ 42.5	$ 57.5	$ 84.0
State income taxes, net of federal benefit		8.6	8.3	3.0
Effect of U.S. tax law change	$ (88.9)	0.0	0.0	(88.9)
Federal credits		(2.3)	(2.0)	(1.0)
Other, net		(1.2)	(3.5)	(2.3)
Total		$ 47.6	$ 60.3	$ (5.2)

Income Taxes (Summary Of Deferred Tax Assets And Deferred Tax Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Property costs and asset retirement obligations	$ 3.7	$ 3.3
Employee benefits	6.1	6.3
Operating leases liability	25.0
Other deferred tax assets	2.1	2.6
Total gross deferred tax assets	36.9	12.2
Deferred tax liabilities
Accumulated depreciation and amortization	(191.2)	(171.6)
State deferred taxes	(27.9)	(25.9)
Operating leases right of use assets	(24.8)
Other deferred tax liabilities	(9.7)	(6.9)
Total gross deferred tax liabilities	(253.6)	(204.4)
Net deferred tax liabilities	$ (216.7)	$ (192.2)

Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Tax benefit related to Tax Cuts and Jobs Act	$ 88,900,000	$ 0	$ 0	$ 88,900,000
Income tax expense (benefit), net benefits for interest and penalties		0	1,600,000	400,000
Accounting Standards Update 2016-09
Income Tax Contingency [Line Items]
Excess tax benefits		$ 100,000	$ 2,500,000	$ 2,200,000

Income Taxes (Reconciliation of Beginning and Ending Liability For Uncertain Tax Positions) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	$ 0.7	$ 4.4
Additions for tax positions related to prior years	0.5	0.0
Additions for tax positions related to current year	0.0	0.2
Settlements with taxing authorities	(0.6)	(3.9)
Expiration of statutes of limitation	0.0	0.0
Balance at December 31	$ 0.6	$ 0.7

Incentive Plans (Narrative) (Details)	12 Months Ended			76 Months Ended
Incentive Plans (Narrative) (Details)	Dec. 31, 2019 USD ($) $ / shares company shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) company shares	Feb. 12, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	99,400
Unrecognized compensation cost related to stock option awards \| $	$ 14,100,000			$ 14,100,000
Unrecognized compensation cost related to stock option awards, weighted average period for recognition (in years)	1 year 9 months 18 days
Total income tax benefits realized from tax deductions related to stock option exercises under share-based payment arrangements \| $	$ 100,000	$ 2,100,000	$ 600,000
2013 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for incentive plan (in shares)					5,500,000
Maximum number of shares per employee (in shares)	1,000,000
Maximum amount payable \| $	$ 5,000,000.0
Shares granted (in shares)				2,339,812
Shares available for grant (in shares)	3,160,188			3,160,188
2013 Stock Plan For Non-Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for incentive plan (in shares)	500,000			500,000
Shares available for grant (in shares)	376,371			376,371
Restricted stock units issued (in shares)				123,629
2013 Stock Plan For Non-Employee Directors \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)	13,086
Award vesting period (in years)	3 years
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 76.63
MUSA 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)	74,118
Option term (in years)	7 years
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 80.85
MUSA 2013 Plan \| Return On Average Capital Employed Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 76.15
MUSA 2013 Plan \| Total Shareholder Return Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Number of companies in total shareholder return peer comparison group \| company	19			19
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 100.65
MUSA 2013 Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years

Incentive Plans (Schedule of Share-Based Plan Amounts Recognized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Payment Arrangement [Abstract]
Compensation charged against income before income tax benefit	$ 10.5	$ 9.2	$ 7.5
Related income tax benefit recognized in income	$ 2.2	$ 1.9	$ 2.6

Incentive Plans (Summary of Valuation Assumptions) (Details) - MUSA 2013 Plan - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per option grant (in dollars per share)	$ 20.48	$ 17.32	$ 15.45
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	26.80%	27.00%	26.00%
Risk-free interest rate	2.50%	2.43%	1.65%
Expected life (in years)	4 years 6 months	3 years 10 months 24 days	4 years 2 months 12 days
Stock price at valuation date (usd per share)	$ 76.15	$ 71.00	$ 65.75

Incentive Plans (Summary of Changes in Stock Options Outstanding) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019
Number of Shares (in shares)
Beginning balance (in shares)	310,362
Granted (in shares)	99,400
Exercised (in shares)	(12,662)
Forfeited (in shares)	(4,800)
Ending balance (in shares)	392,300
Exercisable (in shares)	174,300
Average Exercise Price (in dollars per share)
Beginning balance (in dollars per share)	$ 65.71
Granted (in dollars per share)	76.15
Exercised (in dollars per share)	56.63
Forfeited (in dollars per share)	76.15
Ending balance (in dollars per share)	68.52
Shares exercisable, average exercise price (in dollars per share)	$ 64.00
Options outstanding, average remaining life (in years)	4 years 3 months 18 days
Options exercisable, average remaining life (in years)	3 years
Outstanding, aggregate intrinsic value	$ 19.0
Options exercisable, aggregate intrinsic value	$ 9.2

Incentive Plans (Summary of Additional Stock Option Information) (Details)	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	392,300
Options outstanding, average remaining life (in years)	4 years 3 months 18 days
Options exercisable (in shares)	174,300
Options exercisable, average remaining life (in years)	3 years
$39.46 to $49.99
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Lower range limit of exercise price (in dollars per share) \| $ / shares	$ 39.46
Upper range limit of exercise price (in dollars per share) \| $ / shares	$ 49.99
Options outstanding (in shares)	3,900
Options outstanding, average remaining life (in years)	1 year 1 month 6 days
Options exercisable (in shares)	3,900
Options exercisable, average remaining life (in years)	1 year 1 month 6 days
$50.00 to $59.99
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Lower range limit of exercise price (in dollars per share) \| $ / shares	$ 50.00
Upper range limit of exercise price (in dollars per share) \| $ / shares	$ 59.99
Options outstanding (in shares)	71,000
Options outstanding, average remaining life (in years)	3 years 1 month 6 days
Options exercisable (in shares)	71,000
Options exercisable, average remaining life (in years)	3 years 1 month 6 days
$60.00 to $69.99
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Lower range limit of exercise price (in dollars per share) \| $ / shares	$ 60.00
Upper range limit of exercise price (in dollars per share) \| $ / shares	$ 69.99
Options outstanding (in shares)	90,550
Options outstanding, average remaining life (in years)	4 years 1 month 6 days
Options exercisable (in shares)	43,550
Options exercisable, average remaining life (in years)	4 years 1 month 6 days
$70.00 to $79.99
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Lower range limit of exercise price (in dollars per share) \| $ / shares	$ 70.00
Upper range limit of exercise price (in dollars per share) \| $ / shares	$ 79.99
Options outstanding (in shares)	226,850
Options outstanding, average remaining life (in years)	4 years 9 months 18 days
Options exercisable (in shares)	55,850
Options exercisable, average remaining life (in years)	2 years 1 month 6 days

Incentive Plans (Summary of Restricted Stock Unit Activity) (Details) $ / shares in Units, $ in Millions	12 Months Ended	76 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
MUSA 2013 Plan
Number of units
Beginning balance (in shares)	193,478
Granted (in shares)	74,118
Vested and issued (in shares)	(54,313)
Forfeited (in shares)	(14,368)
Ending balance (in shares)	198,915	198,915
Weighted Average Grant Date Fair Value (in dollars per share)
Beginning balance (in dollars per share) \| $ / shares	$ 64.02
Granted (in dollars per share) \| $ / shares	80.85
Vested and issued (in dollars per share) \| $ / shares	60.41
Forfeited (in dollars per share) \| $ / shares	73.63
Ending balance (in dollars per share) \| $ / shares	$ 70.58	$ 70.58
Total fair value vested \| $	$ 4.2
Total fair value,outstanding \| $	$ 23.3	$ 23.3
MUSA 2013 Plan \| Performance Units
Number of units
Beginning balance (in shares)	124,412
Granted (in shares)	81,513
Vested and issued (in shares)	(72,125)
Forfeited (in shares)	(2,600)
Ending balance (in shares)	131,200	131,200
Weighted Average Grant Date Fair Value (in dollars per share)
Beginning balance (in dollars per share) \| $ / shares	$ 76.58
Granted (in dollars per share) \| $ / shares	88.40
Vested and issued (in dollars per share) \| $ / shares	73.55
Forfeited (in dollars per share) \| $ / shares	88.40
Ending balance (in dollars per share) \| $ / shares	$ 82.98	$ 82.98
Total fair value vested \| $	$ 5.5
Total fair value,outstanding \| $	$ 15.4	$ 15.4
2013 Stock Plan For Non-Employee Directors
Number of units
Granted (in shares)		123,629
2013 Stock Plan For Non-Employee Directors \| Restricted Stock Units
Number of units
Beginning balance (in shares)	41,017
Granted (in shares)	13,086
Vested and issued (in shares)	(20,496)
Forfeited (in shares)	0
Ending balance (in shares)	33,607	33,607
Weighted Average Grant Date Fair Value (in dollars per share)
Beginning balance (in dollars per share) \| $ / shares	$ 64.27
Granted (in dollars per share) \| $ / shares	76.63
Vested and issued (in dollars per share) \| $ / shares	61.65
Ending balance (in dollars per share) \| $ / shares	$ 70.68	$ 70.68
Total fair value vested \| $	$ 1.6
Total fair value,outstanding \| $	$ 3.9	$ 3.9

Employee and Retiree Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Profit Sharing Plan
Defined Contribution Plan Disclosure [Line Items]
Profit sharing contributions	$ 1.5	$ (0.8)	$ 2.2
Thrift Plan
Defined Contribution Plan Disclosure [Line Items]
Company matching contribution (percent)	100.00%
Employee's maximum contribution matched by Company (percent)	6.00%
Profit sharing percentage 1	5.00%
Profit sharing percentage 2	7.00%
Profit sharing percentage 3	9.00%
Profit sharing contributions	$ 12.9	$ 9.7	$ 12.1

Financial Instruments and Risk Management (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 27, 2019
Derivatives, Fair Value [Line Items]
Cash deposits related to commodity derivative contracts	$ 1,000,000.0	$ 1,000,000
Income (loss) reclassified to interest expense	200,000	$ 0	$ 0
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Notional amount				$ 150,000,000
Gain (loss) on cash flow hedges	900,000
Income tax	200,000
Interest Rate Swap \| Interest expense
Derivatives, Fair Value [Line Items]
Income (loss) reclassified to interest expense	$ 200,000

Earnings Per Share (Narrative) (Details) - USD ($)			1 Months Ended			3 Months Ended	12 Months Ended
Earnings Per Share (Narrative) (Details) - USD ($)	Jul. 24, 2019	Aug. 30, 2013	Jan. 31, 2019	Oct. 31, 2014	May 31, 2014	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity, Class of Treasury Stock [Line Items]
Issuance of stock at the separation and distribution (in shares)		46,743,316
Stock repurchase program, shares acquired (in shares)						379,054	1,898,023	1,994,632
Common stock acquired							$ 165,800,000	$ 144,400,000	$ 206,000,000.0
Stock repurchase program, average price per share (in dollars per share)						$ 77.20	$ 87.35	$ 72.39
July 2019 Share Purchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, shares acquired (in shares)	1,393,626
Common stock acquired	$ 125,000,000.0
Stock repurchase program, remaining amount	$ 275,000,000.0
May 2014 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, shares acquired (in shares)					1,040,636
Stock repurchase program, average price per share (in dollars per share)					$ 48.07
October 2014 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, shares acquired (in shares)				4,169,349
Stock repurchase program, average price per share (in dollars per share)				$ 59.96
January 2016 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, shares acquired (in shares)			7,489,388
Stock repurchase program, average price per share (in dollars per share)			$ 66.76
Stock repurchase program, authorized amount						$ 400,000,000			$ 400,000,000

Earnings Per Share (Reconciliation of Basic and Diluted Earnings Per Share Computations) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings per common share:
Net income	$ 47.6	$ 69.2	$ 32.7	$ 5.3	$ 77.5	$ 45.0	$ 51.8	$ 39.3	$ 154.8	$ 213.6	$ 245.3
Weighted average common shares outstanding (in thousands) (in shares)									31,594	32,674	35,816
Earnings per common share (in dollars per share)	$ 1.56	$ 2.20	$ 1.02	$ 0.16	$ 2.40	$ 1.40	$ 1.59	$ 1.17	$ 4.90	$ 6.54	$ 6.85
Earnings per common share - assuming dilution:
Net income	$ 47.6	$ 69.2	$ 32.7	$ 5.3	$ 77.5	$ 45.0	$ 51.8	$ 39.3	$ 154.8	$ 213.6	$ 245.3
Weighted average common shares outstanding (in thousands) (in shares)									31,594	32,674	35,816
Common equivalent shares:
Share-based awards (in shares)									264	309	340
Weighted average common shares outstanding - assuming dilution (in thousands) (in shares)									31,858	32,983	36,156
Earnings per common share assuming dilution (in dollars per share)	$ 1.54	$ 2.18	$ 1.01	$ 0.16	$ 2.38	$ 1.38	$ 1.58	$ 1.16	$ 4.86	$ 6.48	$ 6.78

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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+ Details

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Other Financial Information (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Income taxes paid (collected), net	$ 26.9	$ 17.4	$ 51.7
Interest paid, net of amounts capitalized	$ 56.6	$ 50.4	$ 41.5

Other Financial Information (Summary Of Changes In Operating Working Capital) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts receivable	$ (33.4)	$ 86.6	$ (41.7)
Inventories	(6.1)	(39.0)	(16.3)
Prepaid expenses and other current assets	(3.3)	11.4	(5.2)
Accounts payable and accrued liabilities	(5.9)	(56.7)	26.9
Income taxes payable	0.0	0.0	(0.6)
Net decrease (increase) in noncash operating working capital	$ (48.7)	$ 2.3	$ (36.9)

Assets and Liabilities Measure at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current and long-term debt	$ (1,038.1)	$ (863.3)
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current and long-term debt	$ (1,069.4)	$ (866.7)

Commitments (Details) - USD ($) $ in Millions	12 Months Ended
Commitments (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Expected future rental payments under operating leases in 2020	$ 14.9
Expected future rental payments under operating leases in 2021	14.3
Expected future rental payments under operating leases in 2022	13.5
Expected future rental payments under operating leases in 2023	13.0
Expected future rental payments under operating leases in 2024	12.2
Rental expense for noncancelable operating leases	$ 21.6
Rental expense for noncancelable operating leases		$ 15.2	$ 14.0
Take-Or-Pay Contracts
Other Commitments [Line Items]
Term of take-or-pay contract	1 year 8 months 12 days
Take-or-pay contract due in 2020	$ 7.9
Take-or-pay contract due in 2021	4.9
Capital Addition Purchase Commitments
Other Commitments [Line Items]
Commitments for capital expenditures	246.9
Construction in Progress
Other Commitments [Line Items]
Commitments for capital expenditures	202.9
Building Improvements
Other Commitments [Line Items]
Commitments for capital expenditures	$ 39.2

Contingencies (Details) $ in Millions	12 Months Ended
Contingencies (Details) $ in Millions	Dec. 31, 2019 USD ($) site
Commitments and Contingencies Disclosure [Abstract]
Number of Superfund sites for which company may be liable \| site	1
Workers' compensation deductible (per occurrence)	$ 1.0
General liability insurance deductible	3.0
Auto liability insurance deductible	0.3
Workers' compensation accrued liability	21.8
Outstanding letters of credit	$ 17.0

Lease Accounting (Narrative) (Details) $ in Millions	12 Months Ended
Lease Accounting (Narrative) (Details) $ in Millions	Dec. 31, 2019 USD ($) contract site	Jan. 01, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Operating leases right of use assets	$ 124.2
Present value of lease liabilities	$ 125.3
Number of leases with restrictive covenants \| site	102
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 year
Lease renewal term	5 years
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	20 years
Lease renewal term	20 years
Land
Lessee, Lease, Description [Line Items]
Number of leases \| contract	215
Terminal
Lessee, Lease, Description [Line Items]
Number of leases \| contract	1
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating leases right of use assets		$ 110.4
Present value of lease liabilities		$ 110.7

Lease Accounting (Leases Reflected on Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Operating leases right of use assets	$ 124.2
Finance	3.0	$ 2.9
Total leased assets	127.2	2.9
Accumulated depreciation	2.2	1.8
Current
Operating	6.8
Finance	1.2
Finance		1.2
Noncurrent
Operating	118.5
Finance	1.2
Finance		1.1
Total lease liabilities	$ 127.7	$ 2.3

Lease Accounting (Lease Cost) (Details) $ in Millions	12 Months Ended
Lease Accounting (Lease Cost) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 14.5
Finance lease cost
Amortization of leased assets	1.2
Interest on lease liabilities	0.1
Net lease costs	$ 15.8

Lease Accounting (Cash Flow Information) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Cash paid for amounts included in the measurement of liabilities
Operating cash flows required by operating leases	$ 13.8
Operating cash flows required by finance leases	0.1
Financing cash flows required by finance leases	$ 1.4

Lease Accounting (Maturity of Lease Liability) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating leases
2020	$ 14.9
2021	14.3
2022	13.5
2023	13.0
2024	12.2
After 2024	148.9
Total lease payments	216.8
less: interest	91.5
Present value of lease liabilities	125.3
Finance leases
2020	1.3
2021	0.9
2022	0.3
2023	0.0
2024	0.0
After 2024	0.0
Total lease payments	2.5
less: interest	0.1
Present value of lease liabilities	$ 2.4

Lease Accounting (Leases Under Topic 840) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Operating leases
2019	$ 13.7
2020	13.3
2021	12.5
2022	11.7
2023	11.1
After 2023	122.6
Total lease payments	184.9
Capital leases
2019	1.5
2020	1.1
2021	0.6
2022	0.1
2023	0.0
After 2023	0.0
Total lease payments	3.3
less: interest	0.2
Present value of minimum payments	$ 3.1

Lease Accounting (Lease Term and Discount Rate) (Details)	Dec. 31, 2019
Weighted average remaining lease term (years)
Finance leases	2 years
Operating leases	15 years 7 months 6 days
Weighted average discount rate
Finance leases	4.80%
Operating leases	6.00%

Business Segments (Summary of Information by Business Segment) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment									1
Segment Reporting Information [Line Items]
Segment income (loss)	$ 47,600	$ 69,200	$ 32,700	$ 5,300	$ 77,500	$ 45,000	$ 51,800	$ 39,300	$ 154,800	$ 213,600	$ 245,300
Revenues from external customers									14,034,600	14,362,900	12,826,600
Interest income									3,200	1,500	1,300
Interest expense									(54,900)	(52,900)	(46,700)
Loss on early debt extinguishment									(14,800)	0	0
Income tax expense (benefit)									47,600	60,300	(5,200)
Significant noncash charges (credits)
Depreciation and amortization									152,200	134,000	116,900
Accretion of asset retirement obligations									2,100	2,000	1,800
Debt extinguishment costs									4,400
Deferred and noncurrent income taxes (benefits)									23,700	37,900	(50,400)
Additions to property, plant and equipment									214,600	193,800	273,700
Total assets at year-end	2,687,200				2,360,800				2,687,200	2,360,800	2,331,000
Operating Segment \| Marketing
Segment Reporting Information [Line Items]
Segment income (loss)									215,000	214,200	295,300
Revenues from external customers									14,034,300	14,362,300	12,826,200
Interest income									0	0	0
Interest expense									(100)	(100)	(100)
Loss on early debt extinguishment									0
Income tax expense (benefit)									66,300	69,500	(2,900)
Significant noncash charges (credits)
Depreciation and amortization									138,900	124,500	110,500
Accretion of asset retirement obligations									2,100	2,000	1,800
Debt extinguishment costs									0
Deferred and noncurrent income taxes (benefits)									32,900	39,000	(61,300)
Additions to property, plant and equipment									155,500	169,200	234,000
Total assets at year-end	2,304,700				2,012,000				2,304,700	2,012,000	2,023,400
Corporate and Other Assets
Segment Reporting Information [Line Items]
Segment income (loss)									(60,200)	(600)	(50,000)
Revenues from external customers									300	600	400
Interest income									3,200	1,500	1,300
Interest expense									(54,800)	(52,800)	(46,600)
Loss on early debt extinguishment									(14,800)
Income tax expense (benefit)									(18,700)	(9,200)	(2,300)
Significant noncash charges (credits)
Depreciation and amortization									13,300	9,500	6,400
Accretion of asset retirement obligations									0	0	0
Debt extinguishment costs									4,400
Deferred and noncurrent income taxes (benefits)									(9,200)	(1,100)	10,900
Additions to property, plant and equipment									59,100	24,600	39,700
Total assets at year-end	$ 382,500				$ 348,800				$ 382,500	$ 348,800	$ 307,600

Guarantor Subsidiaries (Narrative) (Details) - Senior Notes	Dec. 31, 2019	Sep. 13, 2019	Apr. 25, 2017
5.625% senior notes due 2027
Debt Instrument [Line Items]
Interest rate (percent)	5.625%		5.625%
Senior Notes 4.75 Percent Due 2029
Debt Instrument [Line Items]
Interest rate (percent)	4.75%	4.75%

Guarantor Subsidiaries (Consolidating Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 280,300	$ 184,500	$ 170,000	$ 153,800
Accounts receivable—trade, less allowance for doubtful accounts	172,900	138,800
Inventories, at lower of cost or market	227,600	221,500
Prepaid expenses and other current assets	30,000	25,300
Total current assets	710,800	570,100
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019 and $974.2 in 2018	1,807,300
Property, plant and equipment, at cost less accumulated depreciation and amortization	1,807,300	1,748,200
Investments in subsidiaries	0	0
Other assets	169,100	42,500
Total assets	2,687,200	2,360,800	2,331,000
Current liabilities
Current maturities of long-term debt	38,800	21,200
Inter-company accounts payable	0	0
Trade accounts payable and accrued liabilities	466,200	456,900
Total current liabilities	505,000	478,100
Long-term debt, including capitalized lease obligations	999,300	842,100
Deferred income taxes	216,700	192,200
Asset retirement obligations	32,800	30,700
Deferred credits and other liabilities	130,400	10,400
Total liabilities	1,884,200	1,553,500
Stockholders' Equity
Preferred Stock, par $0.01	0	0
Common Stock, par $0.01	500	500
Treasury stock	(1,099,800)	(940,300)
Additional paid in capital (APIC)	538,700	539,000
Retained earnings	1,362,900	1,208,100
Accumulated other comprehensive income (AOCI)	700	0
Total stockholders' equity	803,000	807,300	738,400	697,000
Total liabilities and stockholders' equity	2,687,200	2,360,800
Eliminations
Current assets
Cash and cash equivalents	0	0	0	0
Accounts receivable—trade, less allowance for doubtful accounts	0	0
Inventories, at lower of cost or market	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019 and $974.2 in 2018	0
Property, plant and equipment, at cost less accumulated depreciation and amortization		0
Investments in subsidiaries	(2,735,700)	(2,581,400)
Other assets	0	0
Total assets	(2,735,700)	(2,581,400)
Current liabilities
Current maturities of long-term debt	0	0
Inter-company accounts payable	0	0
Trade accounts payable and accrued liabilities	0	0
Total current liabilities	0	0
Long-term debt, including capitalized lease obligations	0	0
Deferred income taxes	0	0
Asset retirement obligations	0	0
Deferred credits and other liabilities	0	0
Total liabilities	0	0
Stockholders' Equity
Preferred Stock, par $0.01	0	0
Common Stock, par $0.01	(100)	(100)
Treasury stock	0	0
Additional paid in capital (APIC)	(1,368,400)	(1,368,400)
Retained earnings	(1,367,200)	(1,212,900)
Accumulated other comprehensive income (AOCI)	0	0
Total stockholders' equity	(2,735,700)	(2,581,400)
Total liabilities and stockholders' equity	(2,735,700)	(2,581,400)
Parent Company \| Reportable Legal Entities
Current assets
Cash and cash equivalents	0	0	0	0
Accounts receivable—trade, less allowance for doubtful accounts	0	0
Inventories, at lower of cost or market	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019 and $974.2 in 2018	0
Property, plant and equipment, at cost less accumulated depreciation and amortization		0
Investments in subsidiaries	2,591,800	2,437,000
Other assets	0	0
Total assets	2,591,800	2,437,000
Current liabilities
Current maturities of long-term debt	0	0
Inter-company accounts payable	(100)	(100)
Trade accounts payable and accrued liabilities	0	0
Total current liabilities	(100)	(100)
Long-term debt, including capitalized lease obligations	0	0
Deferred income taxes	0	0
Asset retirement obligations	0	0
Deferred credits and other liabilities	0	0
Total liabilities	(100)	(100)
Stockholders' Equity
Preferred Stock, par $0.01	0	0
Common Stock, par $0.01	500	500
Treasury stock	(1,099,800)	(940,300)
Additional paid in capital (APIC)	1,188,800	1,195,100
Retained earnings	2,502,400	2,181,800
Accumulated other comprehensive income (AOCI)	0	0
Total stockholders' equity	2,591,900	2,437,100
Total liabilities and stockholders' equity	2,591,800	2,437,000
Issuer \| Reportable Legal Entities
Current assets
Cash and cash equivalents	279,400	184,000	169,900	153,800
Accounts receivable—trade, less allowance for doubtful accounts	173,000	138,800
Inventories, at lower of cost or market	227,600	221,500
Prepaid expenses and other current assets	29,600	25,100
Total current assets	709,600	569,400
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019 and $974.2 in 2018	1,799,100
Property, plant and equipment, at cost less accumulated depreciation and amortization		1,745,900
Investments in subsidiaries	143,900	144,400
Other assets	169,100	42,500
Total assets	2,821,700	2,502,200
Current liabilities
Current maturities of long-term debt	38,800	21,200
Inter-company accounts payable	196,100	203,000
Trade accounts payable and accrued liabilities	466,200	456,900
Total current liabilities	701,100	681,100
Long-term debt, including capitalized lease obligations	999,300	842,100
Deferred income taxes	216,700	192,200
Asset retirement obligations	32,800	30,700
Deferred credits and other liabilities	130,400	10,400
Total liabilities	2,080,300	1,756,500
Stockholders' Equity
Preferred Stock, par $0.01	0	0
Common Stock, par $0.01	0	0
Treasury stock	0	0
Additional paid in capital (APIC)	578,800	572,800
Retained earnings	161,900	172,900
Accumulated other comprehensive income (AOCI)	700	0
Total stockholders' equity	741,400	745,700
Total liabilities and stockholders' equity	2,821,700	2,502,200
Guarantor Subsidiaries \| Reportable Legal Entities
Current assets
Cash and cash equivalents	900	500	100	0
Accounts receivable—trade, less allowance for doubtful accounts	(100)	0
Inventories, at lower of cost or market	0	0
Prepaid expenses and other current assets	400	200
Total current assets	1,200	700
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019 and $974.2 in 2018	8,200
Property, plant and equipment, at cost less accumulated depreciation and amortization		2,300
Investments in subsidiaries	0	0
Other assets	0	0
Total assets	9,400	3,000
Current liabilities
Current maturities of long-term debt	0	0
Inter-company accounts payable	(41,700)	(48,600)
Trade accounts payable and accrued liabilities	0	0
Total current liabilities	(41,700)	(48,600)
Long-term debt, including capitalized lease obligations	0	0
Deferred income taxes	0	0
Asset retirement obligations	0	0
Deferred credits and other liabilities	0	0
Total liabilities	(41,700)	(48,600)
Stockholders' Equity
Preferred Stock, par $0.01	0	0
Common Stock, par $0.01	100	100
Treasury stock	0	0
Additional paid in capital (APIC)	52,000	52,000
Retained earnings	(1,000)	(500)
Accumulated other comprehensive income (AOCI)	0	0
Total stockholders' equity	51,100	51,600
Total liabilities and stockholders' equity	9,400	3,000
Non-Guarantor Subsidiaries \| Reportable Legal Entities
Current assets
Cash and cash equivalents	0	0	$ 0	$ 0
Accounts receivable—trade, less allowance for doubtful accounts	0	0
Inventories, at lower of cost or market	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,079.2 in 2019 and $974.2 in 2018	0
Property, plant and equipment, at cost less accumulated depreciation and amortization		0
Investments in subsidiaries	0	0
Other assets	0	0
Total assets	0	0
Current liabilities
Current maturities of long-term debt	0	0
Inter-company accounts payable	(154,300)	(154,300)
Trade accounts payable and accrued liabilities	0	0
Total current liabilities	(154,300)	(154,300)
Long-term debt, including capitalized lease obligations	0	0
Deferred income taxes	0	0
Asset retirement obligations	0	0
Deferred credits and other liabilities	0	0
Total liabilities	(154,300)	(154,300)
Stockholders' Equity
Preferred Stock, par $0.01	0	0
Common Stock, par $0.01	0	0
Treasury stock	0	0
Additional paid in capital (APIC)	87,500	87,500
Retained earnings	66,800	66,800
Accumulated other comprehensive income (AOCI)	0	0
Total stockholders' equity	154,300	154,300
Total liabilities and stockholders' equity	$ 0	$ 0

Guarantor Subsidiaries (Consolidating Balance Sheet Information) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Guarantor Subsidiaries [Abstract]
Accounts receivable - trade, allowance for doubtful accounts	$ 1.2	$ 1.1
Accumulated depreciation and amortization	$ 1,079.2
Accumulated depreciation and amortization		$ 974.2
Preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock shares authorized (in shares)	20,000,000	20,000,000
Preferred stock shares outstanding (in shares)	0	0
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock shares authorized (in shares)	200,000,000	200,000,000
Common stock shares issued (in shares)	46,767,164	46,767,164
Treasury stock (in shares)	16,307,048	14,505,681

Guarantor Subsidiaries (Consolidating Income Statement and Comprehensive Income) (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2019

Sep. 30, 2019

Jun. 30, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2018

Jun. 30, 2018

Mar. 31, 2018

Dec. 31, 2019

Dec. 31, 2018

Dec. 31, 2017

$ 3,460,200

$ 3,657,600

$ 3,800,400

$ 3,116,400

$ 3,501,700

$ 3,788,000

$ 3,829,000

$ 3,244,200

$ 14,034,600

$ 14,362,900

$ 12,826,600

559,300

541,300

514,900

152,200

134,000

116,900

144,600

136,200

141,200

2,100

2,000

1,800

13,766,300

14,087,100

12,539,400

100

50,400

0

100

(1,100)

(3,900)

268,500

325,100

283,300

3,200

1,500

1,300

(54,900)

(52,900)

(46,700)

(14,800)

0

400

200

2,200

(66,100)

(51,200)

(43,200)

61,900

91,300

43,300

5,900

100,500

57,000

69,100

47,300

202,400

273,900

240,100

47,600

60,300

(5,200)

47,600

69,200

32,700

5,300

77,500

45,000

51,800

39,300

154,800

213,600

245,300

0

$ 47,600

$ 69,200

$ 32,700

$ 5,300

$ 77,500

$ 45,000

$ 51,800

$ 39,300

154,800

213,600

245,300

700

0

155,500

213,600

245,300

Eliminations

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

(154,300)

(213,100)

(245,300)

(154,300)

(213,100)

(245,300)

0

Parent Company | Reportable Legal Entities

(154,300)

(213,100)

(245,300)

0

0

0

0

0

0

0

0

0

0

0

0

165,800

973,700

0

165,800

973,700

0

165,800

973,700

0

0

165,800

973,700

0

154,800

213,600

245,300

320,600

1,187,300

245,300

0

Issuer | Reportable Legal Entities

320,600

1,187,300

245,300

14,034,600

14,362,900

12,826,600

559,300

541,300

514,900

152,100

134,000

116,900

144,600

136,200

141,200

2,100

2,000

1,800

13,766,200

14,087,100

12,539,400

100

50,400

100

(1,100)

(3,900)

268,600

325,100

283,300

3,200

1,500

1,300

(54,900)

(52,900)

(46,700)

(14,800)

(164,800)

(972,900)

2,200

(231,300)

(1,024,300)

(43,200)

37,300

(699,200)

240,100

47,800

60,400

(5,200)

(10,500)

(759,600)

245,300

(500)

0

(11,000)

(760,100)

245,300

700

0

Guarantor Subsidiaries | Reportable Legal Entities

(10,300)

(760,100)

245,300

0

0

100

0

0

0

100

0

0

0

(100)

0

0

0

0

(600)

0

(600)

0

(700)

(600)

0

(200)

(100)

0

(500)

0

0

(500)

0

0

Non-Guarantor Subsidiaries | Reportable Legal Entities

(500)

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Petroleum product sales

^[1]

11,373,800

11,858,400

10,287,900

Petroleum product sales | Eliminations

^[1]

10,707,400

11,251,100

9,773,200

0

Petroleum product sales | Parent Company | Reportable Legal Entities

0

0

Petroleum product sales | Issuer | Reportable Legal Entities

0

11,373,800

11,858,400

10,287,900

Petroleum product sales | Guarantor Subsidiaries | Reportable Legal Entities

10,707,400

11,251,100

9,773,200

0

Petroleum product sales | Non-Guarantor Subsidiaries | Reportable Legal Entities

0

0

0

Merchandise

2,620,100

2,423,000

2,372,700

Merchandise | Eliminations

2,200,700

2,022,500

1,991,400

0

Merchandise | Parent Company | Reportable Legal Entities

0

0

Merchandise | Issuer | Reportable Legal Entities

0

2,620,100

2,423,000

2,372,700

Merchandise | Guarantor Subsidiaries | Reportable Legal Entities

2,200,700

2,022,500

1,991,400

0

Merchandise | Non-Guarantor Subsidiaries | Reportable Legal Entities

0

0

0

Other operating revenues

Other operating revenues | Eliminations

40,700

81,500

166,000

Other operating revenues | Parent Company | Reportable Legal Entities

0

Other operating revenues | Issuer | Reportable Legal Entities

0

Other operating revenues | Guarantor Subsidiaries | Reportable Legal Entities

40,700

81,500

166,000

Other operating revenues | Non-Guarantor Subsidiaries | Reportable Legal Entities

0