Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2019	Apr. 15, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Entity Registrant Name	TimkenSteel Corporation
Entity Central Index Key	0001598428
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		44,765,909

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net sales	$ 371.0	$ 380.8
Cost of products sold	341.9	359.7
Gross Profit	29.1	21.1
Selling, general and administrative expenses	23.3	24.7
Operating Income (Loss)	5.8	(3.6)
Interest expense	4.2	4.6
Other income, net	(2.7)	(6.4)
Income (Loss) Before Income Taxes	4.3	(1.8)
Provision for income taxes	0.1	0.1
Net Income (Loss)	$ 4.2	$ (1.9)
Per Share Data:
Basic earnings (loss) per share (in dollars per share)	$ 0.09	$ (0.04)
Diluted earnings (loss) per share (in dollars per share)	$ 0.09	$ (0.04)

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 4.2	$ (1.9)
Other comprehensive income, net of tax:
Foreign currency translation adjustments	0.4	0.8
Pension and postretirement liability adjustments	0.1	0.1
Other comprehensive income, net of tax	0.5	0.9
Comprehensive Income (Loss), net of tax	$ 4.7	$ (1.0)

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

+ References + Details

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current Assets
Cash and cash equivalents	$ 7.8	$ 21.6
Accounts receivable, net of allowances (2019 - $1.5 million; 2018 - $1.7 million)	151.3	163.4
Inventories, net	324.3	296.8
Deferred charges and prepaid expenses	3.4	3.5
Other current assets	7.4	6.1
Total Current Assets	494.2	491.4
Property, Plant and Equipment, Net	661.1	674.4
Operating lease right-of-use assets	15.9
Pension assets	12.7	10.5
Intangible assets, net	17.7	17.8
Other non-current assets	3.1	3.5
Total Assets	1,204.7	1,197.6
Current Liabilities
Accounts payable	129.9	160.6
Salaries, wages and benefits	26.6	36.8
Accrued pension and postretirement costs	3.0	3.0
Current operating lease liabilities	5.9	0.0
Other current liabilities	20.3	20.4
Total Current Liabilities	185.7	220.8
Non-Current Liabilities
Convertible notes, net	75.2	74.1
Credit Agreement	140.0	115.0
Non-current operating lease liabilities	10.0
Accrued pension and postretirement costs	241.3	240.0
Deferred income taxes	0.6	0.8
Other non-current liabilities	10.6	11.7
Total Liabilities	663.4	662.4
Shareholders’ Equity
Preferred shares, without par value; authorized 10.0 million shares, none issued	0.0	0.0
Common shares, without par value; authorized 200.0 million shares; issued 2019 and 2018 - 45.7 million shares	0.0	0.0
Additional paid-in capital	841.2	846.3
Retained deficit	(265.0)	(269.2)
Treasury shares - 2019 - 1.0 million; 2018 - 1.1 million	(26.5)	(33.0)
Accumulated other comprehensive loss	(8.4)	(8.9)
Total Shareholders’ Equity	541.3	535.2
Total Liabilities and Shareholders’ Equity	$ 1,204.7	$ 1,197.6

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowances for accounts receivable	$ 1.5	$ 1.7
Preferred shares, authorized (in shares)	10,000,000.0	10,000,000.0
Preferred shares, issued (in shares)	0	0
Common shares, authorized (in shares)	200,000,000.0	200,000,000.0
Common shares, issued (in shares)	45,700,000	45,700,000
Treasury shares (in shares)	1,000,000	1,100,000

Consolidated Statements of Shareholder's Equity (Unaudited) - USD ($) $ in Millions	Total	Common Shares	Additional Paid-in Capital	Retained Earnings (Deficit)	Treasury Shares	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2017		44,445,747
Beginning balance at Dec. 31, 2017	$ 560.7		$ 843.7	$ (238.0)	$ (37.4)	$ (7.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(1.9)			(1.9)
Other comprehensive income	0.9					0.9
Stock-based compensation expense	2.2		2.2
Stock option activity	0.1		0.1
Issuance of treasury shares (in shares)		121,012
Issuance of treasury shares			(3.4)	(0.1)	3.5
Shares surrendered for taxes (in shares		(37,533)
Shares surrendered for taxes	(0.7)				(0.7)
Ending balance (in shares) at Mar. 31, 2018		44,529,226
Ending balance at Mar. 31, 2018	562.0		842.6	(239.3)	(34.6)	(6.7)
Beginning balance (in shares) at Dec. 31, 2018		44,584,668
Beginning balance at Dec. 31, 2018	535.2		846.3	(269.2)	(33.0)	(8.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	4.2			4.2
Other comprehensive income	0.5					0.5
Stock-based compensation expense	2.2		2.2
Stock option activity	0.2		0.2
Issuance of treasury shares (in shares)		261,130
Issuance of treasury shares			(7.5)		7.5
Shares surrendered for taxes (in shares		(79,889)
Shares surrendered for taxes	(1.0)				(1.0)
Ending balance (in shares) at Mar. 31, 2019		44,765,909
Ending balance at Mar. 31, 2019	$ 541.3		$ 841.2	$ (265.0)	$ (26.5)	$ (8.4)

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Activities
Net income (loss)	$ 4.2	$ (1.9)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	17.8	18.5
Amortization of deferred financing fees and debt discount	1.3	1.8
Deferred income taxes	(0.2)	(0.3)
Stock-based compensation expense	2.2	2.2
Pension and postretirement expense (benefit), net	1.8	(1.4)
Pension and postretirement contributions and payments	(2.4)	(2.5)
Changes in operating assets and liabilities:
Accounts receivable, net	12.1	(31.3)
Inventories, net	(27.5)	(28.8)
Accounts payable	(30.7)	35.7
Other accrued expenses	(11.4)	(13.2)
Deferred charges and prepaid expenses	0.1	0.4
Other, net	(0.9)	1.4
Net Cash Used by Operating Activities	(33.6)	(19.4)
Investing Activities
Capital expenditures	(4.4)	(2.2)
Net Cash Used by Investing Activities	(4.4)	(2.2)
Financing Activities
Proceeds from exercise of stock options	0.2	0.1
Shares surrendered for employee taxes on stock compensation	(1.0)	(0.7)
Refunding Bonds repayments	0.0	(30.2)
Repayments on credit agreements	(5.0)	(65.0)
Borrowings on credit agreements	30.0	130.0
Debt issuance costs	0.0	(1.7)
Net Cash Provided by Financing Activities	24.2	32.5
Effect of exchange rate changes on cash	0.0	0.0
Decrease (Increase) In Cash and Cash Equivalents	(13.8)	10.9
Cash and cash equivalents at beginning of period	21.6	24.5
Cash and Cash Equivalents at End of Period	$ 7.8	$ 35.4

Company and Basis of Presentation	3 Months Ended
Company and Basis of Presentation	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Company and Basis of Presentation	Basis of Presentation The accompanying Unaudited Consolidated Financial Statements have been prepared by TimkenSteel Corporation (the Company or TimkenSteel) in accordance with generally accepted accounting principles in the United States (U.S. GAAP) for interim financial information. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) and disclosures considered necessary for a fair presentation have been included. For further information, refer to TimkenSteel’s Audited Consolidated Financial Statements and Notes included in its Annual Report on Form 10-K for the year ended December 31, 2018.

Recent Accounting Pronouncements

3 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Recent Accounting Pronouncements

Adoption of New Accounting Standards

The Company adopted the following Accounting Standard Updates (ASU) in the first quarter of 2019, all of which were effective as of January 1, 2019. The adoption of these standards had no impact on the Unaudited Consolidated Financial Statements or the related Notes to the Unaudited Consolidated Financial Statements.



Standards Adopted	Description
ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting	The standard provides an expanded scope of Topic 718, to include share-based payment transactions for acquiring goods and services from nonemployees.
ASU 2018-02, Reporting Comprehensive Income: Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income	The standard permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of tax reform to retained earnings.
ASU 2017-11, Distinguishing Liabilities from Equity; Derivatives and Hedging	The standard eliminates the requirement to consider “down round” features when determining whether certain equity-linked financial instruments or embedded features are indexed to an entity’s own stock.

On January 1, 2019, the Company adopted ASU 2016-02, “Leases (Topics 842),” which requires lessees to recognize lease liabilities and right-of-use assets on the balance sheet for not only finance (previously capital) leases but also operating leases. The standard also requires additional quantitative and qualitative disclosures. The Company adopted the standard using the modified retrospective transition approach without adjusting comparative periods.

The Company elected certain of the practical expedients permitted under the transition guidance within the new standard as follows:


•	A package of practical expedients to not reassess:


◦	Whether a contract is or contains a lease


◦	Lease classification


◦	Initial direct costs


•	A practical expedient to not reassess certain land easements

The Company has implemented internal controls and lease accounting software to enable the quantification of the expected impact on the Unaudited Consolidated Balance Sheets and to facilitate the calculations of the related accounting entries and disclosures. Adoption of the lease standard resulted in recognition of right-to-use assets and lease liabilities of $16.0 million as of January 1, 2019. Adoption of the lease standard had no impact on the Company’s debt-covenant compliance under its current agreements. Also, the standard did not materially affect the Company’s results of operations or its cash flows. Refer to “Note 9 - Leases” for additional information.

Accounting Standards Issued But Not Yet Adopted

The Company has considered the recent ASUs issued by the Financial Accounting Standards Board summarized below:



Standard Pending Adoption	Description	Effective Date	Anticipated Impact
ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40)	The standard aligns the requirements for capitalizing implementation costs in cloud computing software arrangements with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20)	The standard eliminates, modifies and adds disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans.	January 1, 2021	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2018-13, Fair Value Measurement (Topic 820)	The standard eliminates, modifies and adds disclosure requirements for fair value measurements.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2016-13, Measurement of Credit Losses on Financial Instruments	The standard changes how entities will measure credit losses for most financial assets, including trade and other receivables and replaces the current incurred loss approach with an expected loss model.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.

Inventories

3 Months Ended

Mar. 31, 2019

Inventory Disclosure [Abstract]

Inventories

The components of inventories, net of reserves as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019			December 31, 2018
Manufacturing supplies		$52.5			$46.9
Raw materials	51.8			35.2
Work in process	170.6			155.7
Finished products	132.5			142.8
Gross inventory	407.4			380.6
Allowance for surplus and obsolete inventory	(5.1		)	(5.1		)
LIFO reserve	(78.0		)	(78.7		)
Total Inventories, net		$324.3			$296.8

Inventories are valued at the lower of cost or market, with approximately 74% valued by the last in, first out (LIFO) method, and the remaining inventories, including manufacturing supplies inventory as well as international (outside the United States) inventories, valued by first-in, first-out, average cost or specific identification methods.

An actual valuation of the inventory under the LIFO method can be made only at the end of each year based on the inventory levels and costs at that time. Accordingly, interim LIFO calculations must be based on management’s estimates of expected year-end inventory levels and costs. Because these calculations are subject to many factors beyond management’s control, annual results may differ from interim results as they are subject to the final year-end LIFO inventory valuation.

TimkenSteel projects its LIFO reserve will decrease for the year ending December 31, 2019 due primarily to lower anticipated manufacturing costs.

Property, Plant and Equipment

3 Months Ended

Mar. 31, 2019

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

The components of property, plant and equipment, net as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019			December 31, 2018
Land		$14.1			$14.1
Buildings and improvements	426.0			424.4
Machinery and equipment	1,414.1			1,404.2
Construction in progress	18.8			28.5
Subtotal	1,873.0			1,871.2
Less allowances for depreciation	(1,211.9		)	(1,196.8		)
Property, Plant and Equipment, net		$661.1			$674.4

Total depreciation expense was $16.4 million and $17.0 million for the three months ended March 31, 2019 and 2018, respectively.

Intangible Assets

3 Months Ended

Mar. 31, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

The components of intangible assets, net as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019						December 31, 2018
	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
Customer relationships		$6.3		$4.7		$1.6		$6.3		$4.6		$1.7
Technology use	9.0		6.7		2.3		9.0		6.5		2.5
Capitalized software	62.6		48.8		13.8		61.6		48.0		13.6
Total Intangible Assets		$77.9		$60.2		$17.7		$76.9		$59.1		$17.8

Financing Arrangements

3 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Financing Arrangements

For a detailed discussion of the Company's long-term debt and credit arrangements, refer to “Note 6 - Financing Arrangements” in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2018.

Convertible Notes

The components of the Convertible Notes as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019			December 31, 2018
Principal		$86.3			$86.3
Less: Debt issuance costs, net of amortization	(1.1		)	(1.2		)
Less: Debt discount, net of amortization	(10.0		)	(11.0		)
Convertible notes, net		$75.2			$74.1

The initial value of the principal amount recorded as a liability at the date of issuance was $66.9 million, using an effective interest rate of 12.0%. The remaining $19.4 million of principal amount was allocated to the conversion feature and recorded as a component of shareholders’ equity at the date of issuance. This amount represents a discount to the debt to be amortized through interest expense using the effective interest method through the maturity of the Convertible Notes.

Transaction costs were allocated to the liability and equity components based on their relative values. Transaction costs attributable to the liability component of $2.4 million are amortized to interest expense over the term of the Convertible Notes, and transaction costs attributable to the equity component of $0.7 million are included in shareholders’ equity.

The following table sets forth total interest expense recognized related to the Convertible Notes:



	Three Months Ended March 31,
	2019		2018
Contractual interest expense		$1.3		$1.3
Amortization of debt issuance costs	0.1		0.1
Amortization of debt discount	1.0		0.9
Total		$2.4		$2.3

Credit Agreement

On January 26, 2018, the Company, as borrower, and certain domestic subsidiaries, as subsidiary guarantors, entered into the Second Amended and Restated Credit Agreement (Credit Agreement), with JPMorgan Chase Bank, N.A., as administrative agent, Bank of America, N.A., as syndication agent, and the other lenders party thereto, which amended and restated the Company’s Credit Agreement. The interest rate under the Credit Agreement was 4.5% as of March 31, 2019. The amount available under the Credit Agreement as of March 31, 2019 was $157.4 million. As of March 31, 2019, the Company was in compliance with all covenants.

Refunding Bonds

In connection with amending the Credit Agreement, on January 23, 2018, the Company redeemed in full $12.2 million of Ohio Water Development Revenue Refunding Bonds (originally due on November 1, 2025), $9.5 million of Ohio Air Quality Development Revenue Refunding Bonds (originally due on November 1, 2025) and $8.5 million of Ohio Pollution Control Revenue Refunding Bonds (originally due on June 1, 2033).

Fair Value Measurement

The fair value of the Convertible Notes was approximately $102.3 million as of March 31, 2019. The fair value of the Convertible Notes, which falls within Level 1 of the fair value hierarchy as defined by Accounting Standards Codification (ASC) 820, Fair Value Measurements, is based on the last price traded in March 2019.

TimkenSteel’s Credit Agreement is variable-rate debt. As such, the carrying value is a reasonable estimate of fair value as interest rates on these borrowings approximate current market rates. This valuation falls within Level 2 of the fair value hierarchy and is based on quoted prices for similar assets and liabilities in active markets that are observable either directly or indirectly.

Interest Paid

The total cash interest paid for the three months ended March 31, 2019 and 2018 was $1.8 million and $0.9 million, respectively.

Accumulated Other Comprehensive Loss

3 Months Ended

Mar. 31, 2019

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Accumulated Other Comprehensive Loss

Changes in accumulated other comprehensive loss for the three months ended March 31, 2019 and 2018 by component were as follows:



	Foreign Currency Translation Adjustments			Pension and Postretirement Liability Adjustments			Total
Balance as of December 31, 2018		($7.3	)		($1.6	)		($8.9	)
Other comprehensive income before reclassifications, before income tax	0.4			—			0.4
Amounts reclassified from accumulated other comprehensive loss, before income tax	—			0.1			0.1
Income tax	—			—			—
Net current period other comprehensive income, net of income taxes	0.4			0.1			0.5
Balance as of March 31, 2019		($6.9	)		($1.5	)		($8.4	)

	Foreign Currency Translation Adjustments			Pension and Postretirement Liability Adjustments			Total
Balance at December 31, 2017		($5.9	)		($1.7	)		($7.6	)
Other comprehensive income before reclassifications, before income tax	0.8			—			0.8
Amounts reclassified from accumulated other comprehensive loss, before income tax	—			0.1			0.1
Income tax	—			—			—
Net current period other comprehensive income, net of income taxes	0.8			0.1			0.9
Balance as of March 31, 2018		($5.1	)		($1.6	)		($6.7	)

The amount reclassified from accumulated other comprehensive loss for the pension and postretirement liability adjustment was included in other income, net in the Unaudited Consolidated Statements of Operations. These accumulated other comprehensive loss components are components of net periodic benefit cost. See “Note 8 - Retirement and Postretirement Plans” for additional information.

Retirement and Postretirement Benefits

3 Months Ended

Mar. 31, 2019

Defined Benefit Plan [Abstract]

Retirement and Postretirement Plans

The components of net periodic benefit cost (income) for the three months ended March 31, 2019 and 2018 were as follows:



	Three Months Ended March 31, 2019						Three Months Ended March 31, 2018
	Pension			Postretirement			Pension			Postretirement
Service cost		$4.3			$0.3			$4.3			$0.4
Interest cost	12.2			2.0			11.4			1.9
Expected return on plan assets	(16.2		)	(0.9		)	(18.4		)	(1.2		)
Amortization of prior service cost	0.1			—			0.1			0.1
Net Periodic Benefit Cost (Income)		$0.4			$1.4			($2.6	)		$1.2

Leases

3 Months Ended

Mar. 31, 2019

Leases [Abstract]

Leases

Note 9 - Leases

The Company has operating leases for office space, warehouses, land, machinery and equipment, vehicles and certain information technology equipment. These leases have remaining lease terms of one year to six years, some of which may include options to extend the leases for one or more years. Certain leases also include options to purchase the leased property. As of March 31, 2019, the Company has no financing leases and no material leases that have not yet commenced. The weighted average remaining lease term for our operating leases as of March 31, 2019 was 3.0 years.

Leases with an initial term of 12 months or less (short-term leases) are not recorded on the balance sheet; the Company recognizes lease expense for these leases on a straight-line basis over the lease term. For lease agreements entered into after the adoption of ASC 842, the Company combines lease and non-lease components. The Company’s lease agreements do not contain material residual value guarantees or material restrictive covenants.

The Company recorded lease cost for the three months ended March 31, 2019 as follows:



	Three Months Ended March 31, 2019
Operating lease cost		$1.8
Short-term lease cost	0.5
Total lease cost		$2.3

When available, the rate implicit in the lease is used to discount lease payments to present value; however, the Company’s leases generally do not provide a readily determinable implicit rate. Therefore, the incremental borrowing rate to discount the lease payments is estimated using market-based information available at lease commencement. The weighted average discount rate used to measure our operating lease liabilities as of March 31, 2019 was 4.7%.

Supplemental cash flow information related to leases was as follows:



	Three Months Ended March 31, 2019
Cash paid for amounts included in the measurement of operating lease liabilities		$1.8
Right-of-use assets obtained in exchange for operating lease obligations		$1.6

Future minimum lease payments under non-cancellable leases as of March 31, 2019 were as follows:



2019 (excluding the three months ended March 31, 2019)		$5.0
2020	5.8
2021	3.8
2022	1.6
2023	0.8
After 2023	0.1
Total future minimum lease payments	17.1
Less amount of lease payment representing interest	(1.2		)
Total present value of lease payments		$15.9

Future minimum lease payments under non-cancellable leases as of December 31, 2018 were as follows:



2019		$6.3
2020	5.2
2021	3.3
2022	1.0
2023	0.6
After 2023	—
Total future minimum lease payments		$16.4

Revenue Recognition

3 Months Ended

Mar. 31, 2019

Revenue from Contract with Customer [Abstract]

Revenue Recognition

TimkenSteel recognizes revenue from contracts at a point in time when it has satisfied its performance obligation and the customer obtains control of the goods, at the amount that reflects the consideration the Company expects to receive for those goods. The Company receives and acknowledges purchase orders from its customers which define the quantity, pricing, payment and other applicable terms and conditions. In some cases, the Company receives a blanket purchase order from its customer, which includes pricing, payment and other terms and conditions, with quantities defined at the time the customer issues periodic releases against the blanket purchase order. Certain contracts contain variable consideration, which primarily consists of rebates that are accounted for in net sales and accrued based on the estimated probability of the requirements being met. Amounts billed to customers related to shipping and handling costs are included in net sales and related costs are included in costs of products sold in the Unaudited Consolidated Financial Statements.

The following table provides the major sources of revenue by end-market sector for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019		2018
Mobile		$144.2		$142.5
Industrial	147.0		147.7
Energy	60.8		49.1
Other⁽¹⁾	19.0		41.5
Total Net Sales		$371.0		$380.8

⁽¹⁾“Other” for sales by end-market sector includes the Company’s scrap and OCTG billet sales.

The following table provides the major sources of revenue by product type for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019		2018
Bar		$239.9		$234.4
Tube	49.6		63.7
Value-add	73.7		72.7
Other⁽²⁾	7.8		10.0
Total Net Sales		$371.0		$380.8

⁽²⁾“Other” for sales by product type includes the Company’s scrap sales.

Earnings Per Share

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

Earnings Per Share

Note 11 - Earnings Per Share

Basic earnings (loss) per share is computed based upon the weighted average number of common shares outstanding. Diluted earnings (loss) per share is computed based upon the weighted average number of common shares outstanding plus the dilutive effect of common share equivalents calculated using the treasury stock method or if-converted method. For the Convertible Notes, the Company utilizes the if-converted method to calculate diluted earnings (loss) per share. Under the if-converted method, the Company adjusts net earnings to add back interest expense (including amortization of debt discount) recognized on the Convertible Notes and includes the number of shares potentially issuable related to the Convertible Notes in the weighted average shares outstanding. Treasury stock is excluded from the denominator in calculating both basic and diluted earnings (loss) per share.

For the three months ended March 31, 2019 and 2018, 2.3 million and 3.4 million shares issuable for equity-based awards, respectively, were excluded from the computation of diluted loss per share because the effect of their inclusion would have been anti-dilutive. In periods in which a net loss has occurred, as is the case for the three months ended March 31, 2018, the dilutive effect of equity-based awards is not recognized and thus not utilized in the calculation of diluted loss per share, because the effect of their inclusion would have been anti-dilutive. The shares potentially issuable of 6.9 million, related to the Convertible Notes, were also anti-dilutive for the three months ended March 31, 2019 and 2018, respectively.

The following table sets forth the reconciliation of the numerator and the denominator of basic and diluted earnings (loss) per share for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019		2018
Numerator:
Net income (loss)		$4.2		($1.9	)

Denominator:
Weighted average shares outstanding, basic	44.7		44.5
Dilutive effect of stock-based awards	0.5		—
Weighted average shares outstanding, diluted	45.2		44.5

Basic earnings (loss) per share		$0.09		($0.04	)
Diluted earnings (loss) per share		$0.09		($0.04	)

Income Tax Provision

3 Months Ended

Mar. 31, 2019

Income Tax Disclosure [Abstract]

Income Tax Provision

TimkenSteel’s provision for income taxes in interim periods is computed by applying the appropriate estimated annual effective tax rates to income or loss before income taxes for the period. In addition, non-recurring or discrete items, including interest on prior-year tax liabilities, are recorded during the periods in which they occur.



	Three Months Ended March 31,
	2019			2018
Provision for incomes taxes		$0.1			$0.1
Effective tax rate	1.1		%	(5.6		)%

In light of TimkenSteel’s recent operating performance in the U.S. and current industry conditions, the Company assessed, based upon all available evidence, and concluded that it was more likely than not that it would not realize its U.S. deferred tax assets. As a result, the Company will maintain a full valuation allowance against its deferred tax assets in the U.S. and applicable foreign countries until sufficient positive evidence exists to conclude that a valuation allowance is not necessary. Going forward, the need to maintain valuation allowances against deferred tax assets in the U.S. and other affected countries will cause variability in the Company’s effective tax rate.

Contingencies	3 Months Ended
Contingencies	Mar. 31, 2019
Loss Contingency Accrual, Disclosures [Abstract]
Contingencies	Contingencies TimkenSteel has a number of loss exposures incurred in the ordinary course of business, such as environmental claims, product warranty claims, and litigation. Establishing loss reserves for these matters requires management’s estimate and judgment regarding risk exposure and ultimate liability or realization. These loss reserves are reviewed periodically and adjustments are made to reflect the most recent facts and circumstances. As of March 31, 2019 and December 31, 2018, TimkenSteel had a $1.3 million and a $1.5 million contingency reserve, respectively, related to loss exposures incurred in the ordinary course of business.

Other Income, Net

3 Months Ended

Mar. 31, 2019

Other Income and Expenses [Abstract]

Other Income, Net

The following table provides the components of other income, net for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019			2018
Pension and postretirement non-service benefit income		$2.8			$6.3
Foreign currency exchange (loss) gain	(0.1		)	0.1
Total other income, net		$2.7			$6.4

Non-service benefit income is derived from the Company’s pension and other postretirement plans. The Company’s expected return on assets has exceeded the interest cost component, resulting in income for the three months ended March 31, 2019 and 2018. Foreign currency exchange loss (gain) is due to exchange-rate fluctuations on the Company’s various foreign-currency denominated transactions.

Subsequent Event	3 Months Ended
Subsequent Event	Mar. 31, 2019
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event After reviewing the TimkenSteel retiree group health plan in comparison to health insurance options available in the individual market, TimkenSteel announced on April 9, 2019 that it would be moving Medicare-eligible union retirees to an individual plan on a Medicare healthcare exchange. The plans on the exchange offer more options and flexibility than these retirees currently have, and typically cost them less for comparable or better health and prescription drug coverage. The Company is providing these retirees access to a personal benefits advisor as well as additional informational resources to assist with the transition by July 31, 2019. The Company will continue to provide financial support for eligible premiums and expenses through the payment of subsidies ranging from $1,200 to $1,800 annually into the retirees’ Health Reimbursement Accounts (HRAs). The Company concluded this plan change will be accounted for as a plan amendment in the Company’s second quarter of 2019. The Company estimates it will recognize a reduction in the accumulated postretirement benefit obligation (APBO) of approximately $65 to $70 million. The reduction in the APBO will be recognized in Other Comprehensive Income and subsequently amortized as an offset to postretirement benefit cost over a period of approximately 12 years (average remaining service period). Excluding the impact of the mark-to-market adjustment, which cannot be determined at this time, will reduce the Company’s expected 2019 postretirement benefit cost by approximately $5 million. The Company will perform a remeasurement at April 30, 2019.

Recent Accounting Pronouncements (Policies)

3 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Adoption of New Accounting Standards

The Company adopted the following Accounting Standard Updates (ASU) in the first quarter of 2019, all of which were effective as of January 1, 2019. The adoption of these standards had no impact on the Unaudited Consolidated Financial Statements or the related Notes to the Unaudited Consolidated Financial Statements.



Standards Adopted	Description
ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting	The standard provides an expanded scope of Topic 718, to include share-based payment transactions for acquiring goods and services from nonemployees.
ASU 2018-02, Reporting Comprehensive Income: Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income	The standard permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of tax reform to retained earnings.
ASU 2017-11, Distinguishing Liabilities from Equity; Derivatives and Hedging	The standard eliminates the requirement to consider “down round” features when determining whether certain equity-linked financial instruments or embedded features are indexed to an entity’s own stock.

On January 1, 2019, the Company adopted ASU 2016-02, “Leases (Topics 842),” which requires lessees to recognize lease liabilities and right-of-use assets on the balance sheet for not only finance (previously capital) leases but also operating leases. The standard also requires additional quantitative and qualitative disclosures. The Company adopted the standard using the modified retrospective transition approach without adjusting comparative periods.

The Company elected certain of the practical expedients permitted under the transition guidance within the new standard as follows:


•	A package of practical expedients to not reassess:


◦	Whether a contract is or contains a lease


◦	Lease classification


◦	Initial direct costs


•	A practical expedient to not reassess certain land easements

The Company has implemented internal controls and lease accounting software to enable the quantification of the expected impact on the Unaudited Consolidated Balance Sheets and to facilitate the calculations of the related accounting entries and disclosures. Adoption of the lease standard resulted in recognition of right-to-use assets and lease liabilities of $16.0 million as of January 1, 2019. Adoption of the lease standard had no impact on the Company’s debt-covenant compliance under its current agreements. Also, the standard did not materially affect the Company’s results of operations or its cash flows. Refer to “Note 9 - Leases” for additional information.

Accounting Standards Issued But Not Yet Adopted

The Company has considered the recent ASUs issued by the Financial Accounting Standards Board summarized below:



Standard Pending Adoption	Description	Effective Date	Anticipated Impact
ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40)	The standard aligns the requirements for capitalizing implementation costs in cloud computing software arrangements with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20)	The standard eliminates, modifies and adds disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans.	January 1, 2021	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2018-13, Fair Value Measurement (Topic 820)	The standard eliminates, modifies and adds disclosure requirements for fair value measurements.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2016-13, Measurement of Credit Losses on Financial Instruments	The standard changes how entities will measure credit losses for most financial assets, including trade and other receivables and replaces the current incurred loss approach with an expected loss model.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.

Recent Accounting Pronouncements (Tables)

3 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Schedule of Accounting Changes

The Company has considered the recent ASUs issued by the Financial Accounting Standards Board summarized below:



Standard Pending Adoption	Description	Effective Date	Anticipated Impact
ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40)	The standard aligns the requirements for capitalizing implementation costs in cloud computing software arrangements with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20)	The standard eliminates, modifies and adds disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans.	January 1, 2021	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2018-13, Fair Value Measurement (Topic 820)	The standard eliminates, modifies and adds disclosure requirements for fair value measurements.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.
ASU 2016-13, Measurement of Credit Losses on Financial Instruments	The standard changes how entities will measure credit losses for most financial assets, including trade and other receivables and replaces the current incurred loss approach with an expected loss model.	January 1, 2020	The Company is currently evaluating the impact of the adoption of this ASU on its results of operations and financial condition.

The Company adopted the following Accounting Standard Updates (ASU) in the first quarter of 2019, all of which were effective as of January 1, 2019. The adoption of these standards had no impact on the Unaudited Consolidated Financial Statements or the related Notes to the Unaudited Consolidated Financial Statements.



Standards Adopted	Description
ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting	The standard provides an expanded scope of Topic 718, to include share-based payment transactions for acquiring goods and services from nonemployees.
ASU 2018-02, Reporting Comprehensive Income: Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income	The standard permits entities to reclassify tax effects stranded in accumulated other comprehensive income as a result of tax reform to retained earnings.
ASU 2017-11, Distinguishing Liabilities from Equity; Derivatives and Hedging	The standard eliminates the requirement to consider “down round” features when determining whether certain equity-linked financial instruments or embedded features are indexed to an entity’s own stock.

Inventories (Tables)

3 Months Ended

Mar. 31, 2019

Inventory Disclosure [Abstract]

Schedule of Components of Inventory

The components of inventories, net of reserves as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019			December 31, 2018
Manufacturing supplies		$52.5			$46.9
Raw materials	51.8			35.2
Work in process	170.6			155.7
Finished products	132.5			142.8
Gross inventory	407.4			380.6
Allowance for surplus and obsolete inventory	(5.1		)	(5.1		)
LIFO reserve	(78.0		)	(78.7		)
Total Inventories, net		$324.3			$296.8

Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2019

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

The components of property, plant and equipment, net as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019			December 31, 2018
Land		$14.1			$14.1
Buildings and improvements	426.0			424.4
Machinery and equipment	1,414.1			1,404.2
Construction in progress	18.8			28.5
Subtotal	1,873.0			1,871.2
Less allowances for depreciation	(1,211.9		)	(1,196.8		)
Property, Plant and Equipment, net		$661.1			$674.4

Intangible Assets (Tables)

3 Months Ended

Mar. 31, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets

The components of intangible assets, net as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019						December 31, 2018
	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
Customer relationships		$6.3		$4.7		$1.6		$6.3		$4.6		$1.7
Technology use	9.0		6.7		2.3		9.0		6.5		2.5
Capitalized software	62.6		48.8		13.8		61.6		48.0		13.6
Total Intangible Assets		$77.9		$60.2		$17.7		$76.9		$59.1		$17.8

Financing Arrangements (Tables)

3 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Schedule of Components of Convertible Notes

The components of the Convertible Notes as of March 31, 2019 and December 31, 2018 were as follows:



	March 31, 2019			December 31, 2018
Principal		$86.3			$86.3
Less: Debt issuance costs, net of amortization	(1.1		)	(1.2		)
Less: Debt discount, net of amortization	(10.0		)	(11.0		)
Convertible notes, net		$75.2			$74.1

Schedule of Long-term Debt Instruments

The following table sets forth total interest expense recognized related to the Convertible Notes:



	Three Months Ended March 31,
	2019		2018
Contractual interest expense		$1.3		$1.3
Amortization of debt issuance costs	0.1		0.1
Amortization of debt discount	1.0		0.9
Total		$2.4		$2.3

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Accumulated Other Comprehensive Loss (Tables)

3 Months Ended

Mar. 31, 2019

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss)

Changes in accumulated other comprehensive loss for the three months ended March 31, 2019 and 2018 by component were as follows:



	Foreign Currency Translation Adjustments			Pension and Postretirement Liability Adjustments			Total
Balance as of December 31, 2018		($7.3	)		($1.6	)		($8.9	)
Other comprehensive income before reclassifications, before income tax	0.4			—			0.4
Amounts reclassified from accumulated other comprehensive loss, before income tax	—			0.1			0.1
Income tax	—			—			—
Net current period other comprehensive income, net of income taxes	0.4			0.1			0.5
Balance as of March 31, 2019		($6.9	)		($1.5	)		($8.4	)

	Foreign Currency Translation Adjustments			Pension and Postretirement Liability Adjustments			Total
Balance at December 31, 2017		($5.9	)		($1.7	)		($7.6	)
Other comprehensive income before reclassifications, before income tax	0.8			—			0.8
Amounts reclassified from accumulated other comprehensive loss, before income tax	—			0.1			0.1
Income tax	—			—			—
Net current period other comprehensive income, net of income taxes	0.8			0.1			0.9
Balance as of March 31, 2018		($5.1	)		($1.6	)		($6.7	)

Retirement and Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2019

Defined Benefit Plan [Abstract]

Schedule of Periodic Benefit Cost

The components of net periodic benefit cost (income) for the three months ended March 31, 2019 and 2018 were as follows:



	Three Months Ended March 31, 2019						Three Months Ended March 31, 2018
	Pension			Postretirement			Pension			Postretirement
Service cost		$4.3			$0.3			$4.3			$0.4
Interest cost	12.2			2.0			11.4			1.9
Expected return on plan assets	(16.2		)	(0.9		)	(18.4		)	(1.2		)
Amortization of prior service cost	0.1			—			0.1			0.1
Net Periodic Benefit Cost (Income)		$0.4			$1.4			($2.6	)		$1.2

Leases (Tables)

3 Months Ended

Mar. 31, 2019

Leases [Abstract]

Lease, Cost

The Company recorded lease cost for the three months ended March 31, 2019 as follows:



	Three Months Ended March 31, 2019
Operating lease cost		$1.8
Short-term lease cost	0.5
Total lease cost		$2.3

Supplemental cash flow information related to leases was as follows:



	Three Months Ended March 31, 2019
Cash paid for amounts included in the measurement of operating lease liabilities		$1.8
Right-of-use assets obtained in exchange for operating lease obligations		$1.6

Future Lease Maturity

Future minimum lease payments under non-cancellable leases as of March 31, 2019 were as follows:



2019 (excluding the three months ended March 31, 2019)		$5.0
2020	5.8
2021	3.8
2022	1.6
2023	0.8
After 2023	0.1
Total future minimum lease payments	17.1
Less amount of lease payment representing interest	(1.2		)
Total present value of lease payments		$15.9

Future Lease Maturity

Future minimum lease payments under non-cancellable leases as of December 31, 2018 were as follows:



2019		$6.3
2020	5.2
2021	3.3
2022	1.0
2023	0.6
After 2023	—
Total future minimum lease payments		$16.4

Revenue Recognition (Tables)

3 Months Ended

Mar. 31, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

The following table provides the major sources of revenue by end-market sector for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019		2018
Mobile		$144.2		$142.5
Industrial	147.0		147.7
Energy	60.8		49.1
Other⁽¹⁾	19.0		41.5
Total Net Sales		$371.0		$380.8

⁽¹⁾“Other” for sales by end-market sector includes the Company’s scrap and OCTG billet sales.

The following table provides the major sources of revenue by product type for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019		2018
Bar		$239.9		$234.4
Tube	49.6		63.7
Value-add	73.7		72.7
Other⁽²⁾	7.8		10.0
Total Net Sales		$371.0		$380.8

⁽²⁾“Other” for sales by product type includes the Company’s scrap sales.

Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted



	Three Months Ended March 31,
	2019		2018
Numerator:
Net income (loss)		$4.2		($1.9	)

Denominator:
Weighted average shares outstanding, basic	44.7		44.5
Dilutive effect of stock-based awards	0.5		—
Weighted average shares outstanding, diluted	45.2		44.5

Basic earnings (loss) per share		$0.09		($0.04	)
Diluted earnings (loss) per share		$0.09		($0.04	)

Income Tax Provision (Tables)

3 Months Ended

Mar. 31, 2019

Income Tax Disclosure [Abstract]

Schedule of (Benefit) Provision for Income Taxes



	Three Months Ended March 31,
	2019			2018
Provision for incomes taxes		$0.1			$0.1
Effective tax rate	1.1		%	(5.6		)%

Other Income, Net (Tables)

3 Months Ended

Mar. 31, 2019

Other Income and Expenses [Abstract]

Schedule of Other Expense, net

The following table provides the components of other income, net for the three months ended March 31, 2019 and 2018:



	Three Months Ended March 31,
	2019			2018
Pension and postretirement non-service benefit income		$2.8			$6.3
Foreign currency exchange (loss) gain	(0.1		)	0.1
Total other income, net		$2.7			$6.4

Recent Accounting Pronouncements - Adoption of New Accounting Standards (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total present value of lease payments	$ 15.9
Right-to-use assets	$ 15.9
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total present value of lease payments		$ 16.0
Right-to-use assets		$ 16.0

Inventories - Schedule of Inventory (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Manufacturing supplies	$ 52.5	$ 46.9
Raw materials	51.8	35.2
Work in process	170.6	155.7
Finished products	132.5	142.8
Gross inventory	407.4	380.6
Allowance for surplus and obsolete inventory	(5.1)	(5.1)
LIFO reserve	(78.0)	(78.7)
Total Inventories, net	$ 324.3	$ 296.8

Inventories - Narrative (Details)	Mar. 31, 2019
Inventory Disclosure [Abstract]
Percentage of LIFO inventory	74.00%

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Land	$ 14.1	$ 14.1
Buildings and improvements	426.0	424.4
Machinery and equipment	1,414.1	1,404.2
Construction in progress	18.8	28.5
Subtotal	1,873.0	1,871.2
Less allowances for depreciation	(1,211.9)	(1,196.8)
Property, Plant and Equipment, net	$ 661.1	$ 674.4

Property, Plant and Equipment - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Depreciation	$ 16.4	$ 17.0

Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 77.9	$ 76.9
Accumulated Amortization	60.2	59.1
Net Carrying Amount	17.7	17.8
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6.3	6.3
Accumulated Amortization	4.7	4.6
Net Carrying Amount	1.6	1.7
Technology use
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9.0	9.0
Accumulated Amortization	6.7	6.5
Net Carrying Amount	2.3	2.5
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	62.6	61.6
Accumulated Amortization	48.8	48.0
Net Carrying Amount	$ 13.8	$ 13.6

Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense for intangible assets	$ 1.4	$ 1.5

Financing Arrangements - Schedule of Convertible Debt (Details) - Convertible Notes - Convertible Senior Notes - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	May 31, 2016
Debt Instrument [Line Items]
Principal	$ 86.3	$ 86.3
Less: Debt issuance costs, net of amortization	(1.1)	(1.2)	$ (2.4)
Less: Debt discount, net of amortization	(10.0)	(11.0)
Net carrying amount	$ 75.2	$ 74.1	$ 66.9

Financing Arrangements - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
	Jan. 23, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	May 31, 2016
Debt Instrument [Line Items]
Revenue refunding bonds repayments		$ 0.0	$ 30.2
Interest paid		1.8	$ 0.9
Convertible Senior Notes \| Convertible Notes
Debt Instrument [Line Items]
Initial value of principal		75.2		$ 74.1	$ 66.9
Effective interest rate					12.00%
Principal amount allocated to conversion feature					$ 19.4
Transaction costs, debt		1.1		$ 1.2	2.4
Transaction costs, equity component of convertible debt					$ 0.7
Fair value of convertible notes		$ 102.3
Variable-rate State of Ohio Water Development Revenue Refunding Bonds, maturing on November 1, 2025 \| Revenue Refunding Bonds
Debt Instrument [Line Items]
Revenue refunding bonds repayments	$ 12.2
Variable-rate State of Ohio Air Quality Development Revenue Refunding Bonds, maturing on November 1, 2025 \| Revenue Refunding Bonds
Debt Instrument [Line Items]
Revenue refunding bonds repayments	9.5
Variable-rate State of Ohio Pollution Control Revenue Refunding Bonds, maturing on June 1, 2033 \| Revenue Refunding Bonds
Debt Instrument [Line Items]
Revenue refunding bonds repayments	$ 8.5
Credit Agreement \| Second Amended Credit Facility
Debt Instrument [Line Items]
Effective interest rate		4.50%
Amount available under amended credit agreement		$ 157.4

Financing Arrangements - Schedule of Interest Expense (Details) - Convertible Notes - Convertible Senior Notes - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Debt Instrument [Line Items]
Contractual interest expense	$ 1.3	$ 1.3
Amortization of debt issuance costs	0.1	0.1
Amortization of debt discount	1.0	0.9
Total	$ 2.4	$ 2.3

Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income before reclassifications, before income tax	$ 0.8	$ 0.4
Amounts reclassified from accumulated other comprehensive loss, before income tax	0.1	0.1
Income tax	0.0	0.0
Net current period other comprehensive income, net of income taxes	0.9	0.5
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(5.9)	(7.3)
Other comprehensive income before reclassifications, before income tax	0.8	0.4
Amounts reclassified from accumulated other comprehensive loss, before income tax	0.0	0.0
Income tax	0.0	0.0
Net current period other comprehensive income, net of income taxes	0.8	0.4
Ending Balance	(5.1)	(6.9)
Pension and Postretirement Liability Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(1.7)	(1.6)
Other comprehensive income before reclassifications, before income tax	0.0	0.0
Amounts reclassified from accumulated other comprehensive loss, before income tax	0.1	0.1
Income tax	0.0	0.0
Net current period other comprehensive income, net of income taxes	0.1	0.1
Ending Balance	(1.6)	(1.5)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(7.6)	(8.9)
Ending Balance	$ (6.7)	$ (8.4)

Retirement and Postretirement Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 4.3	$ 0.3
Interest cost	12.2	2.0
Expected return on plan assets	(16.2)	(0.9)
Amortization of prior service cost	0.1	0.0
Net Periodic Benefit Cost (Income)	0.4	1.4
Postretirement
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	4.3	0.4
Interest cost	11.4	1.9
Expected return on plan assets	(18.4)	(1.2)
Amortization of prior service cost	0.1	0.1
Net Periodic Benefit Cost (Income)	$ (2.6)	$ 1.2

Leases - Narrative (Details)	3 Months Ended
Leases - Narrative (Details)	Mar. 31, 2019
Lessee, Lease, Description [Line Items]
Extension term	1 year
Remaining lease term for operating leases	3 years
Weighted average discount rate used to measure operating lease liabilities	4.70%
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	6 years

Leases - Lease Cost (Details) $ in Millions	3 Months Ended
Leases - Lease Cost (Details) $ in Millions	Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 1.8
Short-term lease cost	0.5
Total lease cost	$ 2.3

Leases - Supplemental Cash Flow Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($)
Leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 1.8
Right-of-use assets obtained in exchange for operating lease obligations	$ 1.6

Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
2019 (excluding the three months ended March 31, 2019)	$ 5.0
2019		$ 6.3
2020	5.8
2020		5.2
2021	3.8
2021		3.3
2022	1.6
2022		1.0
2023	0.8
2023		0.6
After 2023	0.1
After 2023		0.0
Total future minimum lease payments	17.1
Total future minimum lease payments		$ 16.4
Less amount of lease payment representing interest	(1.2)
Total present value of lease payments	$ 15.9

Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
Revenue Recognition (Details) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Net sales	$ 371.0	$ 380.8
Bar
Disaggregation of Revenue [Line Items]
Net sales	239.9	234.4
Tube
Disaggregation of Revenue [Line Items]
Net sales	49.6	63.7
Value-add
Disaggregation of Revenue [Line Items]
Net sales	73.7	72.7
Other
Disaggregation of Revenue [Line Items]
Net sales	7.8	10.0
Mobile
Disaggregation of Revenue [Line Items]
Net sales	144.2	142.5
Industrial
Disaggregation of Revenue [Line Items]
Net sales	147.0	147.7
Energy
Disaggregation of Revenue [Line Items]
Net sales	60.8	49.1
Other
Disaggregation of Revenue [Line Items]
Net sales	$ 19.0	$ 41.5

Earnings Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income (loss)	$ 4.2	$ (1.9)
Denominator:
Weighted average shares outstanding, basic (in shares)	44.7	44.5
Dilutive effect of stock-based awards (in shares)	0.5	0.0
Weighted average shares outstanding, diluted (in shares)	45.2	44.5
Basic earnings (loss) per share (in dollars per share)	$ 0.09	$ (0.04)
Diluted earnings (loss) per share (in dollars per share)	$ 0.09	$ (0.04)
Equity-Based Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	2.3	3.4
Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	6.9	6.9

Income Tax Provision - Schedule of Provision for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Provision for incomes taxes	$ 0.1	$ 0.1
Effective tax rate	1.10%	(5.60%)

Contingencies - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Loss Contingency Accrual, Disclosures [Abstract]
Contingency reserves	$ 1.3	$ 1.5

Other Income, Net (Details) - USD ($) $ in Millions	3 Months Ended
Other Income, Net (Details) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018
Other Income and Expenses [Abstract]
Pension and postretirement non-service benefit income	$ 2.8	$ 6.3
Foreign currency exchange (loss) gain	(0.1)	0.1
Total other income, net	$ 2.7	$ 6.4

Subsequent Event (Details) - Subsequent Event - USD ($)		12 Months Ended
Subsequent Event (Details) - Subsequent Event - USD ($)	Apr. 09, 2019	Dec. 31, 2019
Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Reduction in accumulated postretirement benefit obligation for plan amendment, period for amortization	12 years
Minimum \| Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected subsidies to be paid to Health Reimbursement Accounts per retiree	$ 1,200
Reduction in accumulated postretirement benefit obligation for plan amendment	65,000,000
Maximum \| Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected subsidies to be paid to Health Reimbursement Accounts per retiree	1,800
Reduction in accumulated postretirement benefit obligation for plan amendment	$ 70,000,000
Scenario, Forecast
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Reduction in postretirement benefit cost from plan amendment		$ 5,000,000

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 700,000
Treasury Stock [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	0
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	700,000
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	0
Additional Paid-in Capital [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 0