Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2016	Feb. 02, 2017	Jun. 30, 2016
Class of Stock [Line Items]
Entity Registrant Name	Spirit AeroSystems Holdings, Inc.
Entity Central Index Key	0001364885
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Amendment Flag	false
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 5,471,118,287
Trading Symbol	SPR
Class A [Member]
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		121,626,875
Class B [Member]
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		0

Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 29, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Oct. 01, 2015	Jul. 02, 2015	Apr. 02, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Net Revenues	$ 1,570.0	$ 1,711.4	$ 1,829.9	$ 1,681.6	$ 1,609.4	$ 1,593.6	$ 1,698.7	$ 1,742.2	$ 6,792.9	$ 6,643.9	$ 6,799.2
Operating costs and expenses
Cost of sales									5,803.6	5,532.3	5,711.0
Selling, general and administrative									228.3	220.8	233.8
Unusual or Infrequent Item, or Both, Net of Insurance Proceeds									12.1	0.0	0.0
Research and development									23.8	27.8	29.3
Loss on divestiture of programs - income statement									0.0	0.0	471.1
Total operating costs and expenses									6,067.8	5,780.9	6,445.2
Operating income (loss)	160.9	214.4	83.3	266.5	205.8	191.6	230.3	235.3	725.1	863.0	354.0
Interest expense and financing fee amortization									(57.3)	(52.7)	(88.1)
Other (expense) income, net									7.3	2.2	3.5
Income (loss) before income taxes and equity in net income of affiliates									660.5	808.1	262.4
Income tax (provision) benefit									(192.1)	(20.6)	95.9
Income (loss) before equity in net income of affiliates									468.4	787.5	358.3
Equity in net income of affiliates									1.3	1.2	0.5
Net income (loss)	$ 108.2	$ 145.1	$ 44.8	$ 171.6	$ 138.3	$ 313.6	$ 154.9	$ 181.9	$ 469.7	$ 788.7	$ 358.8
Earnings (loss) per share
Basic (in dollars per share)	$ 0.90	$ 1.16	$ 0.35	$ 1.30	$ 1.02	$ 2.25	$ 1.11	$ 1.31	$ 3.72	$ 5.69	$ 2.55
Diluted (in dollars per share)	$ 0.89	$ 1.16	$ 0.35	$ 1.29	$ 1.01	$ 2.24	$ 1.11	$ 1.30	3.70	5.66	2.53
Common Stock, Dividends, Per Share, Declared									$ 0.10	$ 0.00	$ 0.00

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income (loss)	$ 469.7	$ 788.7	$ 358.8
Other comprehensive (loss) income, net of tax:
Less: reclassification adjustment for loss realized in net other assets, net of tax effect	0.0	0.7	0.0
Pension, SERP and Retiree medical adjustments, net of tax	36.9	12.5	(78.0)
Unrealized foreign exchange gain (loss) on intercompany loan, net of effect	(9.9)	(3.5)	(3.5)
Foreign currency translation adjustments	(53.4)	(16.4)	(16.6)
Total other comprehensive (loss) income	(26.4)	(6.7)	(99.2)
Total comprehensive income (loss)	443.3	782.0	259.6
Interest rate swaps [Member]
Other comprehensive (loss) income, net of tax:
Unrealized gain (loss) on derivatives arising during period, net of tax effect	$ 0.0	$ 0.0	$ (1.1)

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension, SERP and Retiree medical adjustments, tax	$ (20.8)	$ (7.7)	$ 1.3
Unrealized foreign exchange gain (loss) on intercompany loan, tax	2.5	0.9	1.0
Foreign Exchange Contract [Member]
Unrealized gain (loss) on derivatives arising during period, tax	0.0	0.0	0.0
Reclassification adjustment on derivatives, tax	$ 0.0	$ (0.4)	$ 0.0

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 697.7	$ 957.3
Accounts receivable, net	660.5	537.0
Inventory, net	1,515.3	1,774.4
Other current assets	36.9	30.4
Total current assets	2,910.4	3,299.1
Property, plant and equipment, net	1,991.6	1,950.7
Pension assets	282.3	246.9
Deferred tax asset-non-current, net	128.8	162.8
Other assets	220.9	267.8
Total assets	5,405.2	5,764.5
Current liabilities
Accounts payable	579.7	618.2
Accrued expenses	216.2	230.2
Profit sharing	101.4	61.6
Current portion of long-term debt	26.7	34.9
Advance payments, short-term	199.3	178.3
Deferred revenue, short-term	312.1	285.5
Deferred grant income liability — current	14.4	11.9
Other current liabilities	94.4	37.7
Total current liabilities	1,544.2	1,458.3
Long-term debt	1,060.0	1,085.3
Advance payments, long-term	342.0	507.4
Pension/OPEB obligation	43.9	67.7
Deferred grant income liability — non-current	63.4	82.3
Deferred revenue and other deferred credits	146.8	170.0
Other liabilities	276.1	273.5
Equity
Preferred stock, par value $0.01, 10,000,000 shares authorized, no shares issued	0.0	0.0
Additional paid-in capital	1,078.9	1,051.6
Accumulated other comprehensive loss	(186.9)	(160.5)
Retained earnings	2,113.9	1,656.2
Treasury Stock, Value	(1,078.8)	(429.2)
Total shareholders' equity	1,928.3	2,119.5
Noncontrolling interest	0.5	0.5
Total equity	1,928.8	2,120.0
Total liabilities and equity	5,405.2	5,764.5
Class A [Member]
Equity
Common stock	1.2	1.4
Class B [Member]
Equity
Common stock	$ 0.0	$ 0.0

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Shareholders' equity
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Treasury Stock, Shares	23,936,092	9,691,865
Class A [Member]
Shareholders' equity
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	121,642,556	135,617,589
Class B [Member]
Shareholders' equity
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	0	121

Consolidated Statements of Changes in Shareholders Equity - USD ($)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Stockholders' Equity, Total [Member]	Treasury Stock, Common [Member]
Treasury Stock, Value	$ 0
Balance, shares at Dec. 31, 2013		144,798,123
Balance at Dec. 31, 2013		$ 1,400,000	$ 1,025,000,000	$ (54,600,000)	$ 508,700,000	$ 1,480,500,000
Net income (loss)	358,800,000				358,800,000	358,800,000
Equity in joint venture					(867,500,000)
Employee equity awards, shares		719,214
Employee equity awards, value						8,200,000
Stock forfeitures, shares		249,444
Net shares settled		256,332
Payments Related to Tax Withholding for Share-based Compensation	0
Stock Forfeitures, value			(8,200,000)			0
Excess tax benefits from share-based payment arrangements			2,400,000			2,400,000
SERP shares issued		77,562
Treasury Stock, Value, Acquired, Cost Method	(129,200,000)
Other Comprehensive Income	$ (99,200,000)			(99,200,000)		(99,200,000)
Balance, shares at Dec. 31, 2014	141,100,000	141,089,123
Balance at Dec. 31, 2014		$ 1,400,000	1,035,600,000	(153,800,000)		1,621,500,000	$ (200,000)
Treasury Stock, Carrying Basis	$ (4,000,000)
Treasury Stock, Value	(129,200,000)
Net income (loss)	788,700,000					788,700,000
Employee equity awards, shares		653,011
Employee equity awards, value			26,000,000			26,000,000
Stock forfeitures, shares		170,789
Net shares settled		395,447
Payments Related to Tax Withholding for Share-based Compensation	$ (20,700,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0
Excess tax benefits from share-based payment arrangements			10,700,000			10,700,000
SERP shares issued		133,677
Treasury Stock, Value, Acquired, Cost Method	$ (300,000,000)
Stock Repurchased During Period, Value	(300,000,000)
Other Comprehensive Income	$ (6,700,000)			(6,700,000)		(6,700,000)
Balance, shares at Dec. 31, 2015	135,600,000	135,617,710
Balance at Dec. 31, 2015	$ 2,119,500,000	$ 1,400,000	1,051,600,000	(160,500,000)	1,656,200,000	2,119,500,000
Treasury Stock, Carrying Basis	(5,691,865)
Treasury Stock, Value	(429,200,000)
Net income (loss)	469,700,000					469,700,000
Dividends, Common Stock, Cash	(12,000,000)
Employee equity awards, shares		856,232
Employee equity awards, value			42,500,000			42,500,000
Stock forfeitures, shares		280,349
Net shares settled		335,436
Payments Related to Tax Withholding for Share-based Compensation	$ (15,200,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0
Excess tax benefits from share-based payment arrangements			(200,000)			(200,000)	$ 200,000
SERP shares issued		28,626
Treasury Stock, Value, Acquired, Cost Method	$ (649,600,000)
Stock Repurchased During Period, Value	(649,600,000)
Other Comprehensive Income	$ (26,400,000)			(26,400,000)		(26,400,000)
Balance, shares at Dec. 31, 2016	121,600,000	121,642,556
Balance at Dec. 31, 2016	$ 1,928,300,000	$ 1,200,000	$ 1,078,900,000	$ (186,900,000)	$ 2,113,900,000	$ 1,928,300,000
Treasury Stock, Carrying Basis	(14,244,227)
Treasury Stock, Value	$ (1,078,800,000)

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities
Net income (loss)	$ 469.7	$ 788.7	$ 358.8
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation expense	208.6	180.5	170.2
Amortization expense	0.2	0.6	5.8
Amortization of deferred financing fees	19.3	6.9	23.3
Accretion of customer supply agreement	4.9	2.6	1.1
Employee stock compensation expense	42.5	26.0	16.4
Excess tax benefit of share-based payment arrangements	0.1	(10.7)	(2.6)
Loss from interest rate swaps	0.0	0.0	0.5
Loss (gain) from hedge contracts	0.0	1.6	(1.4)
Loss (gain) from foreign currency transactions	17.4	8.6	10.5
Loss on sale of divestiture of programs - cash flow	0.0	0.0	(471.1)
Loss on disposition of assets	0.4	14.7	13.7
Deferred taxes	0.9	(162.2)	(8.4)
Long-term tax benefit	0.0	0.0	(1.2)
Pension and other post retirement benefits, net	3.5	(26.0)	(24.0)
Grant income	(11.9)	(10.4)	(8.6)
Equity in net income of affiliates	(1.3)	(1.2)	(0.5)
Changes in assets and liabilities
Accounts receivable, net	(139.1)	62.2	(64.7)
Inventory, net	207.8	(44.2)	(332.2)
Accounts payable and accrued liabilities	(34.3)	(89.1)	(22.1)
Profit sharing/deferred compensation	40.5	(50.0)	73.8
Advance payments	(144.4)	(113.3)	(52.9)
Income taxes receivable/payable	(3.3)	251.9	(177.9)
Deferred revenue and other deferred credits	12.4	407.3	2.2
Proceeds from Divestiture of Businesses, Net of Cash Divested	0.0	0.0	(160.0)
Other	23.0	45.2	70.7
Net cash provided by operating activities	716.9	1,289.7	361.6
Investing activities
Purchase of property, plant and equipment	(254.0)	(360.1)	(220.2)
Proceeds from sale of assets	0.6	2.7	0.5
Repayments of Notes Payable	300.0	0.0	300.0
Increase (Decrease) in Restricted Cash	0.0	0.0	(19.9)
Net cash used in investing activities	(253.4)	(357.4)	(239.6)
Payments Related to Tax Withholding for Share-based Compensation	(15.2)	(20.7)	0.0
Financing activities
Proceeds from issuance of debt	0.0	535.0	0.0
Principal payments of debt	36.4	36.5	16.8
Excess tax benefit of share-based payment arrangements	(0.1)	10.7	2.6
Debt issuance and financing costs	17.2	4.7	20.8
Payments for Repurchase of Common Stock	(649.6)	(300.0)	(129.2)
Net cash used in financing activities	(718.7)	(351.1)	(164.2)
Repayments of Debt	0.0	(534.9)	0.0
Proceeds from (Repayments of) Notes Payable	299.8	0.0	300.0
Effect of exchange rate changes on cash and cash equivalents	(4.4)	(1.8)	(0.6)
Net increase (decrease) in cash and cash equivalents for the period	(259.6)	579.4	(42.8)
Cash and cash equivalents, beginning of period	957.3	377.9	420.7
Cash and cash equivalents, end of period	697.7	957.3	377.9
Supplemental information
Interest paid	45.2	51.5	69.2
Proceeds from Income Tax Refunds	$ 191.4
Income taxes paid		$ (69.7)	$ 91.1

Nature of Business	12 Months Ended
Nature of Business	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business Spirit Holdings was incorporated in the state of Delaware on February 7, 2005, and commenced operations on June 17, 2005 through the acquisition of Boeing's operations in Wichita, Kansas; Tulsa, Oklahoma and McAlester, Oklahoma (the "Boeing Acquisition") by an investor group led by Onex Partners LP and Onex Corporation (together with its affiliates, "Onex"). Holdings provides manufacturing and design expertise in a wide range of fuselage, propulsion and wing products and services for aircraft original equipment manufacturers and operators through its subsidiary, Spirit AeroSystems, Inc. ("Spirit"). The Company has its headquarters in Wichita, Kansas, with manufacturing facilities in Tulsa and McAlester, Oklahoma; Prestwick, Scotland; Wichita, Kansas; Kinston, North Carolina and Subang, Malaysia. The Company has an assembly facility in Saint-Nazaire, France. The Company is the majority participant in the Kansas Industrial Energy Supply Company ("KIESC"), a tenancy-in-common with other Wichita companies established to purchase natural gas. The Company participates in a joint venture, Taikoo Spirit AeroSystems Composite Co. Ltd. ("TSACCL"), of which Spirit's ownership interest is 31.5%. TSACCL was formed to develop and implement a state-of-the-art composite and metal bond component repair station in the Asia-Pacific region. In March, June and August 2014, certain selling stockholders sold 22,915,300 shares of the Company's class A common stock at prices to the public ranging from $28.62 to $35.90 per share in secondary offerings of the Company's class A common stock. Following the August 2014 offering, Onex no longer held any investment in the Company. On December 8, 2014, Spirit entered into an Asset Purchase Agreement with Triumph Aerostructures - Tulsa, LLC, a wholly-owned subsidiary of Triumph Group Inc. (“Triumph”), to sell Spirit’s G280 and G650 programs (“Gulfstream programs”), consisting of the design, manufacture and support of structural components for the Gulfstream G280 and G650 aircraft in Spirit’s facilities in Tulsa, Oklahoma to Triumph (the “Gulfstream Transaction”). The transaction closed on December 30, 2014. The accompanying consolidated financial statements include the Company’s financial statements and the financial statements of its majority owned or controlled subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and Regulation S-X. All intercompany balances and transactions have been eliminated in consolidation. Certain reclassifications have been made to the prior year financial statements and notes to conform to the 2016 presentation.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements include the Company’s financial statements and the financial statements of its majority owned or controlled subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and Regulation S-X. Investments in business entities in which the Company does not have control, but has the ability to exercise influence over operating and financial policies, including TSACCL, are accounted for under the equity method. KIESC is fully consolidated as the Company owns 77.8% of the entity's equity. All intercompany balances and transactions have been eliminated in consolidation. The Company's U.K. subsidiary uses local currency, the British pound, as its functional currency; the Malaysian subsidiary uses the British pound and the Singapore subsidiary uses the Singapore dollar. All other foreign subsidiaries and branches use the U.S. dollar as their functional currency.

As part of the monthly consolidation process, the functional currencies of the Company's international subsidiaries are translated to U.S. dollars using the end-of-month translation rate for balance sheet accounts and average period currency translation rates for revenue and income accounts.

Use of Estimates

The preparation of the Company's financial statements in conformity with GAAP requires management to use estimates and assumptions. The results of these estimates form the basis for making judgments which may affect the reported amounts of assets and liabilities, including the impacts of contingent assets and liabilities, and the reported amounts of revenue and expenses during the reporting period.

Provisions for estimated expenses related to service and product warranties and certain extraordinary rework are made at the time products are sold. These costs are accrued at the time of the sale and are recorded to unallocated cost of goods sold. These estimates are established using historical information on the nature, frequency and average cost of warranty claims, including the experience of industry peers. In the case of new development products or new customers, Spirit considers other factors including the experience of other entities in the same business and management judgment, among others.

Actual results could differ from those estimates and assumptions.

Revenues and Profit Recognition

A significant portion of the Company's revenues are recognized under long-term, volume-based pricing contracts, requiring delivery of products over several years. The Company recognizes revenue under the contract method of accounting and records sales and profits on each contract in accordance with the percentage-of-completion method of accounting, primarily using the units-of-delivery method. Under the units-of-delivery method revenue is recognized based upon the number of units delivered during a period and the contract price and expenditures are recognized as the cost allocable to the delivered units. Costs allocable to undelivered units are reported in the balance sheet as inventory. The method is used in circumstances in which an entity produces units of a basic product under production-type contracts in a continuous or sequential production process to buyers' specifications. Recurring long-term production contracts are usually divided into contract blocks for this purpose, with each block treated as a separate contract for "units-of-delivery" production-type contract accounting purposes.

The total quantity of production units to be delivered under a contract may be set as a single contract accounting block, or it can be split into multiple blocks. Unless the life of the contract is so long that it prevents reliable estimates, the entire contract will typically be set as the contract accounting block quantity. "Life-of-program" or "requirements-based" contracts often lead to continuing sales of more than twenty years. Since this is much longer than can be reliably estimated, Spirit uses parameters based on the contract facts and circumstances to determine the length of the contract block. This analysis includes: considering the customer's firm orders, internal assessment of the market, reliability of cost estimates, potential segmentation of non-recurring elements of the contract, and other factors. Contract block sizes may also be determined based on certain contractual terms such as pricing renegotiation dates, such that certain contract blocks may use an approximate date instead of a defined unit quantity in order to increase the ability to estimate accurately given that the renegotiated pricing is unknown for the planning block. Shorter contract blocks for mature, ongoing programs are common due to the presence of recent cost history and probable forecast accuracy. Initial contract blocks often require a longer time period and a greater number of units in order to take into account the higher cost of early units due to a steeper experience curve and pre-production design costs. As these programs mature, costs stabilize and efficiencies are realized, subsequent contract block length shortens to take into account the steady state of the continuing production.

Revenues from non-recurring design work are recognized based on substantive milestones or use of the cost-to-cost method, that are indicative of the Company's progress toward completion depending on facts and circumstances. The Company follows the requirements of Financial Accounting Standards Board ("FASB") authoritative guidance on accounting for the performance of construction-type and certain production-type contracts (the contract method of accounting), and uses the cumulative catch-up method in accounting for revisions in estimates. Under the cumulative catch-up method, the impacts of revisions in estimates are recognized immediately when changes in estimated contract profitability become known.

A profit rate is estimated based on the difference between total revenues and total costs over a contract block. Total revenues at any given time include actual historical revenues up to that time plus future estimated revenues. Total costs at any given time include actual historical costs up to that time plus future estimated costs. Estimated revenues include negotiated or expected values for units delivered, estimates of probable recoveries asserted against the customer for changes in specifications, price adjustments for contract and volume changes, escalation and assumed but currently unnegotiated price increases for derivative models. Costs include the estimated cost of certain pre-production efforts (including non-recurring engineering and planning subsequent to completion of final design) plus the estimated cost of manufacturing a specified number of production units. Estimates take into account assumptions related to future labor performance and rates, and projections related to material and overhead costs including expected "learning curve" cost reductions over the term of the contract. Estimated revenues and costs also take into account the expected impact of specific contingencies that the Company believes are probable.

Estimates of revenues and costs for the Company's contract blocks span a period of multiple years and are based on a substantial number of underlying assumptions. The Company believes that the underlying assumptions are sufficiently reliable to provide a reasonable estimate of the profit to be generated. However, due to the significant length of time over which revenue streams will be generated, the variability of the revenue and cost streams can be significant if the assumptions change. Estimates of profit margins for contract accounting blocks are typically reviewed at least annually or at an earlier point if evidence suggests a change in margin may be necessary. Assuming the initial estimates of sales and costs under the contract block are accurate, the percentage-of-completion method results in the profit margin being recorded evenly as revenue is recognized under the contract block. Changes in these underlying estimates due to revisions in sales and cost estimates may result in profit margins being recognized unevenly over a contract block as such changes are accounted for on a cumulative basis in the period estimates are revised, which the Company refers to as cumulative catch-up adjustments. The Company's Estimate at Completion estimating process is not solely an accounting process, but is instead an integrated part of the management of the Company's business, involving numerous personnel in the Company's planning, production control, contracts, cost management, supply chain and program and business management functions.

Spirit regularly commences work and incorporates customer-directed changes prior to negotiating pricing terms for engineering work, for work related to the modification of the product, and/or other statements of work. Spirit typically has the legal right to negotiate pricing for customer-directed changes. In those cases, Spirit asserts to its customers its contractual rights to be paid the additional revenue or cost reimbursement the Company expects to receive upon finalizing pricing terms.

Spirit’s supply agreement for the B787 program (the "B787 Supply Agreement") provides that initial prices for the B787-9 and B787-10 are to be determined by a procedure set out in the B787 Supply Agreement, and documented by amendment once that amendment has been agreed to by the parties. As part of a memorandum of agreement that Spirit and Boeing entered into in November 2014 (the "November 2014 MOA"), Boeing and Spirit established interim prices for certain B787 shipsets, and the parties agreed to negotiate future rate increases, recurring prices, and other issues across multiple programs during 2015. Since Spirit was unable to reach agreement with Boeing on these issues by the end of 2015, once the parties agree upon appropriate pricing for the B787-9, Boeing will be entitled to a retroactive adjustment on certain B787 payments which were based on the interim pricing. The amount Spirit received that is subject to a retroactive adjustment was recorded as deferred revenue, and has not been recognized by the Company as revenue. Spirit is engaged in discussions with Boeing concerning how to determine the subsequent B787-9 and initial B787-10 prices, and the parties have not yet reached agreement. Spirit’s ability to successfully negotiate fair and equitable prices for these models as well as overall B787 delivery volumes and rate investments, and its ability to achieve forecasted cost improvements on all B787 models are key factors in achieving the projected financial performance for this program.

For B787-9 and B787-10 deliveries in the Company's second B787 contract block, the Company has applied the applicable accounting guidance for unpriced change orders in estimating total block revenues which will be updated as part of the Company’s Estimate at Completion process until the final pricing is negotiated. Pending final price negotiations, the Company has estimated revenue for B787-9 and B787-10 deliveries to include assumptions around changes from the contract configuration baseline for each B787 model.

For revenues not recognized under the contract method of accounting, the Company recognizes revenues from the sale of products at the point of passage of title, which is generally at the time of shipment. Shipping and handling costs are included in cost of sales. Revenues earned from providing maintenance services, including any contracted research and development, are recognized when the service is complete or other contractual milestones are attained. Revenues from non-recurring design work are recognized based on substantive milestones or use of the cost-to-cost method, that are indicative of the Company's progress toward completion. Non-recurring revenues, which are derived primarily from engineering and design efforts, were $302.1, $307.4 and $305.5 for each of the periods ended December 31, 2016, 2015 and 2014, respectively. As required by FASB authoritative guidance related to accounting for consideration given by a vendor to a customer certain payments are amortized as a reduction to revenues on units delivered.

Research and Development

Research and development includes costs incurred for experimentation, design and testing that are expensed as incurred.

Cash and Cash Equivalents

Cash and cash equivalents represent all highly liquid investments with original maturities of three months or less.

Accounts Receivable

Accounts receivable are recorded at the invoiced amount and do not bear interest. Consistent with industry practice, the Company classifies unbilled receivables related to contracts accounted for under the long-term contract method of accounting, as current. The Company determines an allowance for doubtful accounts based on a review of outstanding receivables. Account balances are charged off against the allowance after the potential for recovery is considered remote. The Company's allowance for doubtful accounts was approximately $5.2 and $6.1 at December 31, 2016 and December 31, 2015, respectively.

Accounts receivable, net includes unbilled receivables on long-term aerospace contracts, comprised principally of revenue recognized on contracts for which amounts were earned but not contractually billable as of the balance sheet date, or amounts earned in which the recovery will occur over the term of the contract, which could exceed one year.

Inventory

Raw materials are stated at lower of cost (principally on an actual or average cost basis) or market. Inventoried costs attributed to units delivered under long-term contracts are based on the estimated average cost of all units expected to be produced and are determined under the learning curve concept which anticipates a predictable decrease in unit costs. Lower unit costs are achieved as tasks and production techniques become more efficient through repetition, supply chain costs are reduced as contracts are negotiated and design changes result in lower cost. This cost averaging usually results in an increase in inventory (referred to as "excess-over-average" or "deferred production costs") during the early years of a contract. These costs are deferred only to the extent the amount of actual or expected excess-over-average is reasonably expected to be fully offset by lower-than-average costs in future periods of a contract. If in-process inventory plus estimated costs to complete a specific contract exceed the actual plus anticipated remaining sales value of such contract, such excess is charged to cost of sales in the period the loss becomes known, thus reducing inventory to estimated realizable value. Costs in inventory include amounts relating to contracts with long production cycles, some of which are not expected to be realized within one year.

The Company reviews its general stock materials and spare parts inventory each quarter to identify impaired inventory, including excess or obsolete inventory, based on historical sales trends and expected production usage. Impaired inventories are written off to work-in-process in the period identified.

Property, Plant and Equipment

Property, plant and equipment are stated at cost less accumulated depreciation. Depreciation is applied using a straight-line method over the useful lives of the respective assets as described in the following table:



	Estimated Useful Life
Land improvements	20 years
Buildings	45 years
Machinery and equipment	3-20 years
Tooling — Airplane program — B787, Rolls-Royce	5-20 years
Tooling — Airplane program — all others	2-10 years
Capitalized software	3-7 years

The Company capitalizes certain costs, such as software coding, installation and testing, that are incurred to purchase or to create and implement internal-use computer software. The Company's capitalization policy includes specifications that the software must have a service life greater than one year, is legally and substantially owned by Spirit, and has an acquisition cost of greater than $0.1.

Where the Company is involved in build-to-suit leasing arrangements, the Company is deemed the owner of the asset for accounting purposes during the construction period of the asset. The Company records the related assets and liabilities for construction costs incurred under these build-to-suit leasing arrangements during the construction period. Upon completion of the asset, the Company considers whether the assets and liabilities qualify for derecognition under the sale-leaseback accounting guidance.

Impairment or Disposal of Long-Lived Assets and Goodwill

Spirit reviews capital and amortizing intangible assets (long-lived assets) for impairment on an annual basis or whenever events or changes in circumstances indicate that the recorded amount may not be recoverable. Under the standard, assets must be classified as either held-for-use or available-for-sale. An impairment loss is recognized when the recorded amount of an asset that is held for use exceeds the projected undiscounted future net cash flows expected from its use and disposal, and is measured as the amount by which the recorded amount of the asset exceeds its fair value, which is measured by discounted cash flows when quoted market prices are not available. For assets available-for-sale, an impairment loss is recognized when the recorded amount exceeds the fair value less cost to sell. The Company performs an annual impairment test for goodwill in the fourth quarter of each year, or more frequently, if an event occurs or circumstances change that would more likely than not reduce fair value below current value.

Deferred Financing Costs

Costs relating to long-term debt are deferred and included in other long-term assets. These costs are amortized over the term of the related debt or debt facilities and are included as a component of interest expense.

Derivative Instruments and Hedging Activity

The Company uses derivative financial instruments to manage the economic impact of fluctuations in currency exchange rates and interest rates. Derivative financial instruments are recognized on the consolidated balance sheets as either assets or liabilities and are measured at fair value. Changes in fair value of derivatives are recorded each period in earnings or accumulated other comprehensive income, depending on whether a derivative is effective as part of a hedge transaction, and if it is, the type of hedge transaction. Gains and losses on derivative instruments reported in other comprehensive income are subsequently included in earnings in the periods in which earnings are affected by the hedged item or when the hedge is no longer effective. Cash flows associated with the Company's derivatives are presented as a component of the operating section of the statement of cash flows. The use of derivatives has generally been limited to interest rate swaps and foreign currency forward contracts. The Company enters into foreign currency forward contracts to reduce the risks associated with the changes in foreign exchange rates on sales and cost of sales denominated in currencies other than the entities' functional currency.

Fair Value of Financial Instruments

Financial instruments are measured in accordance with FASB authoritative guidance related to fair value measurements. This guidance clarifies the definition of fair value, prescribes methods for measuring fair value, establishes a fair value hierarchy based on the inputs used to measure fair value, and expands disclosures about fair value measurements. See Note 10, "Fair Value Measurements."

Income Taxes

Income taxes are accounted for in accordance with FASB authoritative guidance on accounting for income taxes. Deferred income tax assets and liabilities are recognized for the future income tax consequences attributable to differences between the financial statement carrying amounts for existing assets and liabilities and their respective tax bases. Tax rate changes impacting these assets and liabilities are recognized in the period during which the rate change occurs.

A valuation allowance, if needed, reduces deferred tax assets to the amount expected to be realized. When determining the amount of net deferred tax assets that are more likely than not to be realized, we assess all available positive and negative evidence. The weight given to the positive and negative evidence is commensurate with the extent the evidence may be objectively verified.

We record an income tax expense or benefit based on the net income earned or net loss incurred in each tax jurisdiction and the tax rate applicable to that income or loss. In the ordinary course of business, there are transactions for which the ultimate tax outcome is uncertain. These uncertainties are accounted for in accordance with FASB authoritative guidance on accounting for the uncertainty in income taxes. The final tax outcome for these matters may be different than management's original estimates made in determining the income tax provision. A change to these estimates could impact the effective tax rate and net income or loss in subsequent periods. We use the flow-through accounting method for tax credits. Under this method, tax credits reduce income tax expense.

Stock-Based Compensation and Other Share-Based Payments

Many of the Company's employees are participants in various stock compensation plans. The expense attributable to the Company's employees is recognized over the period the amounts are earned and vested, as described in Note 15, "Stock Compensation."

New Accounting Pronouncements

In August 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-15, Statement of Cash Flows (Topic 230), Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”). ASU 2016-15 provides guidance on eight specific cash flow classification issues. Current GAAP does not include specific guidance on these eight cash flow classification issues. The amendments of this ASU are effective for reporting periods beginning after December 15, 2017, with early adoption permitted. The adoption of ASU 2016-15 is not expected to have a material impact on the Company's consolidated financial statements.

In March 2016, the FASB issued ASU No. 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting ("ASU 2016-09"). ASU 2016-09 identifies areas for simplification involving several aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, an option to recognize gross stock compensation expense with actual forfeitures recognized as they occur, as well as certain classifications on the statement of cash flows. ASU 2016-09 will be effective for annual periods beginning after December 15, 2016. Early adoption is permitted. The Company elected to early adopt these amendments beginning in the second quarter of 2016. Beginning in that quarter, excess tax benefits or deficiencies in respect of stock-based compensation were reflected in the Consolidated Statements of Operations as a component of the income tax provision. Previously, they were recognized in equity as part of additional paid-in-capital. Also, beginning in that quarter, the Company's Consolidated Statement of Cash Flows presents excess tax benefits or deficiencies as an operating activity. Accordingly, the Consolidated Statement of Cash Flows for the twelve months ended December 31, 2016 includes a $4.6 increase to net cash provided by operating activities. The Company has also elected to account for forfeitures using an expected estimate rather than recording forfeitures as they occur as permitted by ASU 2016-09. See Note 15, Income Taxes, for information regarding the additional impact on the Company's financial statements.

In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) ("ASU 2016-02"). This update requires recognition of lease assets and lease liabilities on the balance sheet of lessees. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018 and interim reporting periods within those years. Early adoption is permitted. ASU 2016-02 requires a modified retrospective transition approach and provides certain optional transition relief. The Company is currently evaluating the new guidance to determine the impact it may have to the Company's consolidated financial statements.

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”, “ASC 606”), which requires recognition of revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The FASB has issued several updates to ASU 2014-09 which must be adopted concurrently with ASU 2014-09.

Under ASC 606, revenue is recognized when control of promised goods or services transfers to a customer and is recognized in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. The major provisions include determining enforceable rights and obligation between parties, defining performance obligations as the units of accounting under contract, accounting for variable consideration, and determining whether performance obligations are satisfied over time or at a point of time. Additionally, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

ASC 606 will be effective for us beginning January 1, 2018 and early adoption as of January 1, 2017 is permitted. The guidance permits two methods of adoption: retrospectively to each prior reporting period presented (“full retrospective method”), or retrospectively with the cumulative effect of initially applying ASC 606 recognized at the date of initial application (“the modified retrospective method”). The Company is adopting ASC 606 effective January 1, 2018 and the Company expects to do so using the modified retrospective method.

In 2016, we established a cross-functional team to assess and prepare for implementation of the new standard. We are progressing in our assessment of the impact of ASC 606 and ASC 340-40 and are concurrently gathering business requirements for the implementation of ASC 606.

While further analysis of ASC 606 and a review of all material contracts is underway the adoption of ASC 606 may impact the amounts and timing of revenue recognition and the accounting treatment of deferred production costs. Under ASC 606, the units-of-delivery method is no longer viable and some performance obligations may be satisfied over time which may change the timing of recognition of revenue and associated production costs for certain contracts.

Changes in Estimates

12 Months Ended

Dec. 31, 2016

Changes in Estimates [Abstract]

Accounting Changes [Text Block]

Changes in Estimates

The Company has a Company-wide quarterly Estimate at Completion (EAC) process in which management assesses the progress and performance of the Company's contracts. This process requires management to review each program’s progress towards completion by evaluating the program schedule, changes to identified risks and opportunities, changes to estimated contract revenues and estimated contract costs over the current contract block and any outstanding contract matters. Risks and opportunities include management's judgment about the cost associated with a program’s ability to achieve the schedule, technical requirements (e.g., a newly-developed product versus a mature product) and any other contract requirements. The majority of the Company's fixed priced contracts are life of aircraft program contracts. Due to the span of years it may take to complete a contract block and the scope and nature of the work required to be performed on those contracts, the estimation of total revenue and costs at completion is complicated and subject to many variables and, accordingly, is subject to change. When adjustments in estimated total contract block revenue or estimated total cost are required, any changes from prior estimates for delivered units are recognized in the current period as a cumulative catch-up adjustment for the inception-to-date effect of such changes. Cumulative catch-up adjustments are driven by several factors including improved production efficiencies, assumed rate of production, the rate of overhead absorption, changes to scope of work and contract modifications. When estimates of total costs to be incurred on a contract block exceed estimates of total revenue to be earned, a provision for the entire loss on the contract block is recorded in the period in which the loss is determined. Changes in estimates are summarized below:



Changes in Estimates	December 31, 2016		December 31, 2015		December 31, 2014
Favorable (Unfavorable) Cumulative Catch-up Adjustments by Segment
Fuselage	13.6		16.1		14.8
Propulsion	(0.4	)	22.8		18.8
Wing	23.4		2.7		26.8
Total Favorable Cumulative Catch-up Adjustment	36.6		41.6		60.4

(Forward Loss) and Changes in Estimates on Loss Programs by Segment
Fuselage	(133.4	)	8.7		9.9
Propulsion	10.1		2.4		16.5
Wing	5.1		(0.3	)	(0.3	)
Total (Forward Loss) and Change in Estimate on Loss Program	(118.2	)	10.8		26.1

Total Change in Estimate	(81.6	)	52.4		86.5
EPS Impact (diluted per share based on statutory rates)	(0.40	)	0.24		0.38

_______________________________________

(1) Includes ($141.8) forward loss charge on the A350 XWB program for the twelve months ended December 31, 2016.

2016 Changes in Estimates

Favorable cumulative catch-up adjustments for the periods prior to 2016 were primarily driven by productivity and efficiency improvements, favorable cost performance, mitigation of risk on maturing programs and favorable pricing negotiations on a maturing program.

During the second quarter of 2016, Spirit signed a memorandum of agreement with Airbus (the "Airbus 2016 MOA") which, in part, materially reset the pricing for 800 units on the A350 XWB Fuselage and Wing requirements contracts. The Airbus 2016 MOA was negotiated to economically compensate Spirit for significant engineering changes to aircraft design. The new pricing provided the Company with a higher degree of certainty of revenue that will be realized over the 800 unit contracts. Further, the Company analyzed A350 XWB market demand using third party publications as well as Airbus firm orders which indicated that the sustained demand for the A350 XWB program was in excess of 800 units. The Company determined that due to the higher degree of precision of the A350 XWB revenue along with the strong, sustained market demand, it was appropriate to extend the accounting block quantity to 800 units in the second quarter of 2016. The contract block quantity change was made in accordance with applicable accounting guidance as well as the Company’s accounting policies and past practices. As a result of the Airbus 2016 MOA, the Company updated its estimated revenues that will be realized over the 800 unit A350 XWB Fuselage and Wing contract accounting blocks.

While the Company continued to make progress on the A350 XWB Fuselage program, the Company experienced various disruption and production inefficiencies that exceeded estimates made in previous quarters primarily related to achieving production rate increases. As a result of these disruptions and inefficiencies, cost estimates were updated in the second quarter of 2016 to account for increased labor costs in fabrication and assembly and expedited shipping costs to meet current and future customer production rate increases. The Company also updated its estimates in the second quarter of 2016 due to uncertainty of supply chain cost reductions and achievement of cost affordability projects. The changes in revenue and cost estimates during the second quarter of 2016 resulted in a net forward loss charge of ($135.7) on the A350 XWB program. Increased scrap and rework as well as increased production labor costs resulted in an additional net forward loss charge of ($6.1) recorded on the A350 XWB program during the fourth quarter of 2016.

For the twelve months ended December 31, 2016, the changes in revenue and cost estimates during the second and fourth quarters of 2016 (as described above) resulted in a net forward loss charge of ($141.8) on the A350 XWB program. The Company could record additional forward loss charges if there are further changes to revenue and cost estimates and/or if risks are not mitigated.

2015 Changes in Estimates

Favorable cumulative catch-up adjustments for the periods prior to 2015 and changes in estimates on loss programs were primarily driven by productivity and efficiency improvements, favorable cost performance, mitigation of risk, benefits from increased production rates related to the absorption of fixed costs and favorable pricing negotiations on a maturing program. Forward loss charges were due to a production rate decrease on a mature program.

2014 Changes in Estimates

Favorable cumulative catch-up adjustments for the periods prior to 2014 and changes in estimates on loss programs were primarily driven by productivity and efficiency improvements, favorable cost performance, mitigation of risk, benefits from increased production rates related to the absorption of fixed costs, increased statement of work on mature programs and favorable pricing negotiations on a maturing program.

Accounts Receivable, net

12 Months Ended

Dec. 31, 2016

Receivables [Abstract]

Accounts Receivable, net

Accounts receivable, net consists of the following:



	December 31, 2016			December 31, 2015
Trade receivables	$	647.3		$	524.3
Other	18.4			18.8
Less: allowance for doubtful accounts	(5.2		)	(6.1		)
Accounts receivable, net	$	660.5		$	537.0

_______________________________________

Accounts receivable, net includes unbilled receivables on long-term aerospace contracts, comprised principally of revenue recognized on contracts for which amounts were earned but not contractually billable as of the balance sheet date, or amounts earned for which the recovery will occur over the term of the contract, which could exceed one year.

- Definition

The entire disclosure for claims held for amounts due a entity, excluding financing receivables. Examples include, but are not limited to, trade accounts receivables, notes receivables, loans receivables. Includes disclosure for allowance for credit losses.

+ References + Details

Inventory

12 Months Ended

Dec. 31, 2016

Inventory Disclosure [Abstract]

Inventory

Capitalized pre-production costs include certain contract costs, including applicable overhead, incurred before a product is manufactured on a recurring basis. Significant statement of work changes considered not reimbursable by the customer can also cause pre-production costs to be incurred. These costs are typically amortized over a certain number of shipset deliveries. Capitalized pre-production may be amortized over multiple blocks. See contract block and orders table noted below.

Deferred production includes costs for the excess of production costs over the estimated average cost per shipset, and credit balances for favorable variances on contracts between actual costs incurred and the estimated average cost per shipset for units delivered under the current production blocks. Recovery of excess-over-average deferred production costs is dependent on the number of shipsets ultimately sold and the ultimate selling prices and lower production costs associated with future production under these contract blocks. The Company believes these amounts, net of forward loss provisions, will be fully recovered over the contract block quantities noted in the contract block and orders table below. Should orders not materialize in future periods to fulfill the block, potential forward loss charges may be necessary to the extent the final delivered quantity does not absorb deferred inventory costs. Sales significantly under estimates or costs significantly over estimates could result in losses on these contracts in future periods.

Capitalized pre-production and deferred production inventories are at risk to the extent that the Company does not achieve the orders in the forecasted blocks or if future actual costs exceed current projected estimates, as those categories of inventory are recoverable over future deliveries.

Forward loss provisions on contract blocks are recorded in the period in which they become evident and included in inventory with any remaining amount reflected in accrued contract liabilities.

Inventories are summarized as follows:



	December 31, 2016			December 31, 2015
Raw materials	$	281.9		$	253.8
Work-in-process	788.6			854.4
Finished goods	30.9			65.7
Product inventory	1,101.4			1,173.9
Capitalized pre-production⁽¹⁾	103.5			167.8
Deferred production⁽²⁾	717.4			1,315.4
Forward loss provision⁽³⁾	(407.0		)	(882.7		)
Total inventory, net	$	1,515.3		$	1,774.4

_______________________________________

For contract blocks that have not closed, the following non-product inventory amounts were included in the summarized inventory table above:


(1)	For the period ended December 31, 2016, $83.7 and $15.2 on the A350 XWB and Rolls-Royce BR725 programs, respectively. For the period ended December 31, 2015, $42.1, $94.2 and $25.9 on the B787, A350 XWB and Rolls-Royce BR725 programs, respectively.


(2)	For the period ended December 31, $657.2 and $114.6 on the A350 XWB and Rolls-Royce BR725 programs, respectively. For the period ended December 31, 2015, $558.5, $679.4 and $95.7 on the B787, A350 XWB and Rolls-Royce BR725 programs, respectively.


(3)	For the period ended December 31, 2016, ($253.7) and ($140.8) on the A350 XWB and Rolls-Royce BR725 programs, respectively. For the period ended December 31, 2015, ($606.0), ($113.8) and ($134.1) on the B787, A350 XWB and Rolls-Royce BR725 programs, respectively.

Significant amortization of capitalized pre-production and deferred production inventory has occurred over the following contract block deliveries and will continue to occur over the following contract blocks:



Model	Current Block Deliveries	Contract Block Quantity
A350 XWB	133	800
Rolls-Royce BR725	257	350

Property, Plant and Equipment, net

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment, net

Property, plant and equipment, net consists of the following:



	December 31, 2016			December 31, 2015
Land	$	14.9		$	16.5
Buildings (including improvements)	642.5			585.4
Machinery and equipment	1,367.0			1,210.6
Tooling	982.4			927.2
Capitalized software	268.8			219.7
Construction-in-progress	193.7			278.6
Total	3,469.3			3,238.0
Less: accumulated depreciation	(1,477.7		)	(1,287.3		)
Property, plant and equipment, net	$	1,991.6		$	1,950.7

Repair and maintenance costs are expensed as incurred. The Company recognized repair and maintenance costs of $123.1, $139.0 and $113.4 for the twelve months ended December 31, 2016, 2015 and 2014, respectively.

The Company capitalizes certain costs, such as software coding, installation and testing, that are incurred to purchase or to create and implement internal use computer software. Depreciation expense related to capitalized software was $18.6, $16.9 and $18.3 for the twelve months ended December 31, 2016, 2015 and 2014, respectively.

The Company reviews capital and amortizing intangible assets (long-lived assets) for impairment on an annual basis or whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The Company evaluated its long-lived assets at its locations and determined that an impairment of $8.3 primarily related to obsolete machinery and equipment and tooling, $10.0 primarily related to obsolete machinery and equipment and $13.1 primarily related to abandoned construction-in-progress projects was necessary for the twelve months ended December 31, 2016, 2015 and 2014, respectively.

Other Assets

12 Months Ended

Dec. 31, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

Other Assets

Other assets are summarized as follows:



	December 31, 2016			December 31, 2015
Intangible assets
Patents	$	1.9		$	1.9
Favorable leasehold interests	6.3			6.3
Total intangible assets	8.2			8.2
Less: Accumulated amortization-patents	(1.8		)	(1.6		)
Accumulated amortization-favorable leasehold interest	(4.2		)	(3.8		)
Intangible assets, net	2.2			2.8
Deferred financing
Deferred financing costs	38.5			36.8
Less: Accumulated amortization-deferred financing costs⁽¹⁾	(32.2		)	(30.3		)
Deferred financing costs, net⁽¹⁾	6.3			6.5
Other
Goodwill — Europe	2.3			2.7
Equity in net assets of affiliates	4.4			3.2
Supply agreement⁽²⁾	17.0			29.3
Restricted Cash	19.9			19.9
Deferred Tax Asset - non-current	128.8			162.8
Other	40.0			40.6
Total	$	220.9		$	267.8

_______________________________________


(1)	In accordance with ASU 2015-03, reflects a retrospective reclassification for the period ended December 31, 2015 of $13.0 net deferred financing costs to a direct deduction from the carrying amount of the related debt liability. See Note 12, "Debt" for further detail.


(2)	Under agreements with a customer and a supplier, certain payments accounted for as consideration given by the Company to a customer and supplier are being amortized as a reduction to net revenues.

Advance Payments and Deferred Revenue/Credits

12 Months Ended

Dec. 31, 2016

Advance Payments And Deferred Revenue Credits [Abstract]

Advance Payments And Deferred Revenue/Credits

Advance Payments and Deferred Revenue/Credits

Advance payments. Advance payments are those payments made to Spirit by customers in contemplation of the future performance of services, receipt of goods, incurrence of expenditures or for other assets to be provided by Spirit under a contract and are repayable if such obligation is not satisfied. The amount of advance payments to be recovered against production units expected to be delivered within a year is classified as a short-term liability on the Company's consolidated balance sheet, with the balance of the unliquidated advance payments classified as a long-term liability.

On April 8, 2014, the Company signed a memorandum of agreement with Boeing which suspended advance repayments related to the B787 program for a period of twelve months beginning April 1, 2014. Repayment recommenced on April 1, 2015 and any repayments which otherwise would have become due during such twelve-month period will be offset against the purchase price for shipsets 1,001 through 1,120.

Deferred revenue/credits. Deferred revenue/credits generally consist of nonrefundable amounts received in advance of revenue being earned for specific contractual deliverables or amounts that could be required to be refunded if certain performance obligations or conditions are not met. These payments are classified as deferred revenue/credits on the Company's Condensed Consolidated Balance Sheet when received and recognized as revenue as the production units are delivered or performance obligations or conditions are met.

In November 2014, Spirit and Boeing entered into a Memorandum of Agreement (the “November 2014 MOA”). As part of the November 2014 MOA, Boeing and Spirit established interim prices for certain B787 shipsets, and the parties agreed to negotiate future rate increases, recurring prices and other issues across multiple programs during 2015. Since the Company was unable to reach agreement with Boeing on these issues by the end of 2015, once the parties agree upon appropriate pricing for the B787-9, Boeing will be entitled to a retroactive adjustment on certain B787 payments which were based on the interim pricing. The amount Spirit received that is subject to a retroactive adjustment was recorded as deferred revenue, and has not been recognized by the Company as revenue. The Company is engaged in discussions with Boeing concerning how to determine the subsequent B787-9 and initial B787-10 prices, and the parties have not yet reached agreement.

Advance payments and deferred revenue/credits are summarized by program as follows:



	December 31, 2016		December 31, 2015
B787	$	834.8	$	909.3
Boeing — All other programs	18.6		13.8
A350 XWB	116.7		183.5
Airbus — All other programs	2.2		4.0
Other	27.9		30.6
Total advance payments and deferred revenue/credits	$	1,000.2	$	1,141.2

Government Grants

12 Months Ended

Dec. 31, 2016

Government Grants [Abstract]

Government Grants

The Company received grants in the form of government funding for a portion of the site construction and other specific capital asset costs at the Company's Kinston, North Carolina and Subang, Malaysia sites. Deferred grant income is being amortized as a reduction to production cost. This amortization is based on specific terms associated with the different grants. In North Carolina, the deferred grant income related to the capital investment criteria, which represents half of the grant, is being amortized over the lives of the assets purchased to satisfy the capital investment performance criteria. The other half of the deferred grant income is being amortized over a ten-year period, which began in 2010, in a manner consistent with the job performance criteria. Under the agreement, failure to meet job performance criteria, including creation of a targeted number of jobs, could result in Spirit making incremental rent payments to the North Carolina Global TransPark Authority over the initial term of the lease. The amount of the incremental rent payments would vary depending on Spirit’s level of attainment of these requirements, not to exceed a certain dollar threshold. In Malaysia, the deferred grant income is being amortized based on the estimated lives of the eligible assets constructed with the grant funds as there are no performance criteria. The assets related to deferred grant income are consolidated within property, plant and equipment.

Deferred grant income liability, net consists of the following:



	2016			2015
Balance, January 1	$	94.2		$	106.3
Grant liability amortized	(11.9		)	(10.4		)
Exchange rate	(4.5		)	(1.7		)
Total liability related to deferred grant income, December 31	$	77.8		$	94.2

The asset related to the deferred grant income consists of the following:



	2016			2015
Balance, January 1	$	106.6		$	113.2
Amortization	(5.0		)	(5.0		)
Exchange rate	4.4			(1.6		)
Total asset value related to deferred grant income, December 31	$	106.0		$	106.6

Fair Value Measurements

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value Measurements

FASB’s authoritative guidance on fair value measurements defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. It also establishes a fair value hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The guidance discloses three levels of inputs that may be used to measure fair value:



Level 1		Quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 1 assets and liabilities include debt and equity securities and derivative contracts that are traded in an active exchange market.
Level 2		Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 2 assets and liabilities include debt securities with quoted prices that are traded less frequently than exchange-traded instruments and derivative contracts whose value is determined using a pricing model with inputs that are observable in the market or can be derived principally from or corroborated by observable market data. Observable inputs, such as current and forward interest rates and foreign exchange rates, are used in determining the fair value of our interest rate swaps and foreign currency hedge contracts.
Level 3		Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of assets and liabilities. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation.



	Fair Value Measurements
	December 31, 2015						At December 31, 2015 using
Description	Total Carrying Amount in Balance Sheet		Assets Measured at Fair Value		Liabilities Measured at Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money Market Fund	$	90.2	$	90.2	$	—	$	90.2	$	—	$	—

At December 31, 2016, the Company did not hold any cash within money market funds.

The Company's long-term debt includes a senior unsecured term loan, senior unsecured notes and the Malaysian term loan. The estimated fair value of the Company's debt obligations is based on the quoted market prices for such obligations or the historical default rate for debt with similar credit ratings. The following table presents the carrying amount and estimated fair value of long-term debt:



	December 31, 2016					December 31, 2015
	Carrying Amount		Fair Value			Carrying Amount		Fair Value
Senior secured term loan A (including current portion)	$	485.2	$	484.8	⁽²⁾	$	505.8	$	501.6	⁽²⁾
Senior unsecured notes due 2020	—		—		⁽¹⁾	296.3		310.5		⁽¹⁾
Senior unsecured notes due 2022	293.8		307.0		⁽¹⁾	292.7		304.8		⁽¹⁾
Senior unsecured notes due 2026	296.9		292.4		⁽¹⁾	—		—		⁽¹⁾
Malaysian loan	1.0		0.9		⁽²⁾	3.2		2.8		⁽²⁾
Total	$	1,076.9	$	1,085.1		$	1,098.0	$	1,119.7

_______________________________________


(1)	Level 1 Fair Value hierarchy


(2)	Level 2 Fair Value hierarchy

- Definition

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

Derivative and Hedging Activities	12 Months Ended
Derivative and Hedging Activities	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative and Hedging Activities	Derivative and Hedging Activities The Company has historically entered into interest rate swap agreements to reduce its exposure to the variable rate portion of its long-term debt. On the inception date, the Company designates a derivative contract as either a fair value or cash flow hedge and links the contract to either a specific asset or liability on the balance sheet, or to forecasted commitments or transactions. The Company assesses, both at the inception of the hedge and on a quarterly basis, whether the derivative item is effective in offsetting changes in fair value or cash flows. Any gains or losses on hedges are included in earnings when the underlying transaction that was hedged occurs. The Company also considers counterparty credit risk and its own credit risk in its determination of all estimated fair values. The Company has historically entered into derivative instruments covered by master netting arrangements whereby, in the event of a default as defined by the senior unsecured credit facility or termination event, the non-defaulting party has the right to offset any amounts payable against any obligation of the defaulting party under the same counterparty agreement. See Note 12, Debt for discussion of the Company's senior unsecured credit facility. Interest Rate Swaps During the first quarter of 2015, as a result of Amendment No. 5 to its Credit Agreement, the Company unwound its interest rate swap agreements which had a notional amount of $250.0. The company recognized a loss of $0.4 as a result of settling these interest rate swaps. This loss on derivatives not designated as hedging instruments is included in Other Expense on the Consolidated Statement of Operations for the twelve months ended December 31, 2015. In total, the Company paid $2.0 as a result of the settlement of the interest rate swap agreements. As of December 31, 2016 and December 31, 2015, the Company had no outstanding interest rate swap agreements.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

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+ Details

Debt

12 Months Ended

Dec. 31, 2016

Debt Disclosure [Abstract]

Debt

Total debt shown on the balance sheet is comprised of the following:



	December 31, 2016				December 31, 2015
	Current		Noncurrent		Current⁽¹⁾		Noncurrent⁽¹⁾
Senior unsecured term loan A	$	24.9	$	460.3	$	26.1	$	479.7
Senior notes due 2020	—		—		—		296.3
Senior notes due 2022	—		293.8		—		292.7
Senior notes due 2026	—		296.9		—		—
Malaysian term loan	1.0		—		2.1		1.1
Present value of capital lease obligations	0.8		9.0		0.6		8.5
Other	—		—		6.1		7.0
Total	$	26.7	$	1,060.0	$	34.9	$	1,085.3


(1)	In connection with the Company's adoption of ASU No. 2015-03 relating to the presentation of debt issuance costs, debt balances at December 31, 2015 include unamortized debt issuance costs of $13.0. These unamortized debt issuance costs were previously included in other long-term assets in the Company's Condensed Consolidated Balance Sheet at December 31, 2015.

Senior Secured Credit Facilities

On June 6, 2016, Spirit and the Company entered into the senior unsecured Amended and Restated Credit Agreement, among Spirit, as borrower, the Company, as parent guarantor, the lenders party thereto, Bank of America, N.A., as administrative agent, and the other agents named therein (the "A&R Credit Agreement"). The A&R Credit Agreement refinanced and replaced the Credit Agreement, dated as of April 18, 2012, as amended by Amendment No. 1, dated as of October 26, 2012, Amendment No. 2, dated as of August 2, 2013, Amendment No. 3, dated as of March 18, 2014, Amendment No. 4, dated as of June 3, 2014 and Amendment No. 5 dated as of March 18, 2015 (the “Prior Credit Agreement”). Certain terms of the A&R Credit Agreement were available to Spirit based on increases to Spirit's senior unsecured debt rating provided by Standard & Poor’s Financial Services LLC (“S&P”) and/or Moody’s Investors Service, Inc. (“Moody’s”). The A&R Credit Agreement provides for a $650.0 revolving credit facility (the “Revolver”) and a $500.0 term loan A facility (the “Term Loan”). Each of the Revolver and the Term Loan has a maturity date of June 4, 2021, and each bears interest, at Spirit’s option, at either LIBOR plus 1.5% or a defined “base rate” plus 0.50%, subject to adjustment to amounts between and including LIBOR plus 1.125% and LIBOR plus 2.0% (or amounts between and including base rate plus 0.125% and base rate plus 1.0%, as applicable) based on changes to Spirit’s senior unsecured debt rating provided by S&P and/or Moody’s, as set forth in the table below. The principal obligations under the Term Loan are to be repaid in equal quarterly installments of $6.25, with the remaining balance due at maturity of the Term Loan. The A&R Credit Agreement removes many of the prepayment requirements contained in the Prior Credit Agreement. The covenant structure was amended and provides the Company with some additional flexibility with respect to certain activities which were previously restricted by affirmative and negative covenants, though the A&R Credit Agreement does continue to contain customary affirmative and negative covenants available to investment grade companies, including certain financial covenants that are tested on a quarterly basis. The A&R Credit Agreement contains an accordion feature that provides Spirit with the option to increase the Revolver commitments and/or institute one or more additional term loans by an amount not to exceed $500.0 in the aggregate, subject to the satisfaction of certain conditions and the participation of the lenders. Spirit used the proceeds of the Term Loan, along with cash on hand, to pay off the outstanding amounts under the term loan A under the Prior Credit Agreement and to pay a portion of the fees and expenses payable in connection with the A&R Credit Agreement.

As of December 31, 2016, the outstanding balance of the Term Loan was $487.5 and the carrying value was $485.2. As a result of extinguishment and modification of the term loan A and the revolver under the Prior Credit Agreement which occurred during the second quarter of 2016, the Company recognized a loss on extinguishment of debt of $1.4 including third party fees of $0.4, all of which is reflected within amortization of deferred financing fees on the Condensed Consolidated Statement of Cash Flows for the twelve months ended December 31, 2016. As a result of extinguishment of a term loan B under the Prior Credit Agreement during the first quarter of 2015, the Company recognized a loss on extinguishment of debt of $3.6. Of this total charge, $3.1 is reflected within amortization of deferred financing fees and $0.5 is reflected within amortization expense on the Condensed Consolidated Statement of Cash Flows for the twelve months ended December 31, 2015.

In addition to paying interest on outstanding principal under the A&R Credit Agreement, Spirit is required to pay an unused line fee at a rate per annum equal to the applicable percentage for the applicable pricing tier set forth in the table below under the heading “Commitment Fee” on the unused portion of the commitments under the revolving credit facility. Spirit is required to pay letter of credit fees at a rate per annum equal to the applicable percentage for the applicable pricing tier set forth in the table below under the heading “Letter of Credit Fee” on the amounts available to be drawn under each standby letter of credit. Spirit is also required to pay fronting fees in respect of letters of credit to the issuing banks and customary administrative fees to the administrative agent. At December 31, 2016, Spirit had no letters of credit outstanding. The Company was subject to pricing tier 3 at December 31, 2016.



Pricing Tier	Credit Rating (S&P/Moody's)	Commitment Fee	Letter of Credit Fee	LIBOR Loans	Base Rate Loans
1	≥BBB+/Baa1	0.125%	1.125%	1.125%	0.125%
2	BBB/Baa2	0.175%	1.250%	1.250%	0.250%
3	BBB-/Baa3	0.225%	1.500%	1.500%	0.500%
4	BB+/Ba1	0.275%	1.750%	1.750%	0.750%
5	≤BB/Ba2	0.350%	2.000%	2.000%	1.000%

The A&R Credit Agreement contains customary affirmative and negative covenants, including restrictions on indebtedness, liens, type of business, acquisitions, investments, sales or transfers of assets, payments of dividends, transactions with affiliates, change in control and other matters customarily restricted in such agreements.

The A&R Credit Agreement also contains the following financial covenants (as defined in the A&R Credit Agreement):



Interest Coverage Ratio		Shall not be less than 4.0:1.0
Total Leverage Ratio		Shall not exceed 3.5:1.0

As of December 31, 2016, Spirit was and expects to remain in full compliance with all covenants contained within the A&R Credit Agreement through December 31, 2017.

Senior Notes

In November 2010, the Company issued $300.0 in aggregate principal amount of 6.75% Senior Notes due December 15, 2020 (the "2020 Notes"), with interest payable, in cash in arrears, on June 15 and December 15 of each year, beginning June 15, 2011. The 2020 Notes are fully and unconditionally guaranteed, jointly and severally, on a senior unsecured basis by the Company and Spirit's existing and future domestic subsidiaries that guarantee Spirit's obligations under Spirit's senior secured credit facility. As described below, as of July 1, 2016 the 2020 Notes were no longer outstanding.

In March 2014, the Company issued the $300.0 aggregate principal amount of 5.25% Senior Notes due March 15, 2022 (the "2022 Notes") with interest payable, in cash in arrears, on March 15 and September 15 of each year, beginning September 15, 2014. The 2022 Notes are unconditionally guaranteed, jointly and severally, on a senior unsecured basis, by the Company and its existing and future domestic subsidiaries that guarantee Spirit's obligations under its amended senior secured credit facility. The carrying value of the 2022 Notes was $293.8 as of December 31, 2016.

On May 24, 2016 the Company commenced an offer to purchase for cash any and all of the $300.0 outstanding principal amount of its 2020 Notes (the “Tender Offer”). Under the terms of the Tender Offer, holders of 2020 Notes who validly tendered their notes at or prior to May 31, 2016 would receive, in whole dollars, $1,037.25 per $1,000 principal amount of the 2020 Notes tendered.

On June 1, 2016, in order to fund the Tender Offer or otherwise acquire, redeem or repurchase the 2020 Notes, the Company issued $300.0 in aggregate principal amount of 3.850% Senior Notes due June 15, 2026 (the "2026 Notes") with interest payable, in cash in arrears, on June 15 and December 15 of each year, beginning December 15, 2016. The indenture governing the 2026 Notes (the “2026 Notes Indenture”) requires that the 2026 Notes be guaranteed by the Company and each of Spirit’s existing and future domestic subsidiaries, if any, that may guarantee Spirit’s obligations under a senior credit facility. In addition, the 2026 Notes Indenture contains covenants that limit Spirit’s, the Company’s and certain of Spirit’s subsidiaries’ ability to create liens without granting equal and ratable liens to the holders of the 2026 Notes or to enter into sale and leaseback transactions. These covenants are subject to a number of qualifications and limitations. The 2026 Notes Indenture also provides for customary events of default. The carrying value of the 2026 Notes was $296.9 as of December 31, 2016.

On June 1, 2016, Spirit repurchased $213.6 aggregate principal amount of its 2020 Notes pursuant to the Tender Offer. Tender fees related to the early extinguishment of the 2020 Notes were $8.0, which are included within debt issuance cost on the Condensed Consolidated Statement of Cash Flows for the twelve months ended December 31, 2016.

In addition, on June 1, 2016, Spirit called for redemption of the remaining $86.4 aggregate principal amount of 2020 Notes outstanding following completion of the Tender Offer. The redemption price of the 2020 Notes was 103.375% of the principal amount thereof, plus accrued and unpaid interest to, but not including, the redemption date of July 1, 2016. Following the redemption on July 1, 2016, none of the 2020 Notes remained outstanding.

As a result of the extinguishment of the 2020 Notes, the Company recognized a loss on extinguishment of the 2020 Notes of $11.5, all of which is reflected within amortization of deferred financing fees on the Condensed Consolidated Statement of Cash Flows for the twelve months ended December 31, 2016.

As of December 31, 2016, we were and expect to remain in full compliance with all covenants contained in the indentures governing the 2022 Notes and the 2026 Notes through December 31, 2017.

Pension and Other Post-Retirement Benefits

12 Months Ended

Dec. 31, 2016

Pension and Other Postretirement Benefit Expense [Abstract]

Pension and Other Post-Retirement Benefits

Multi-employer Pension Plan

In connection with the collective bargaining agreement signed with the International Association of Machinists and Aerospace Workers ("IAM"), the Company contributes to a multi-employer defined benefit pension plan ("IAM National Pension Fund"). The level of contribution, as specified in the bargaining agreement was, in whole dollars, $1.75 per hour of employee service as of July 1, 2015. The IAM bargaining agreement provides for a $0.05 per hour increase, in whole dollars, effective July 1 of each year through 2019.

The collective bargaining agreement with the International Union, Automobile, Aerospace and Agricultural Implement Workers of America ("UAW") requires the Company to contribute a specified amount per hour of service to the IAM National Pension Fund. The specified amount was $1.60 in 2016. Per the negotiated UAW collective bargaining agreement, the pension contributions, in whole dollars, will be as follows:

Effective 1/1/2016 — $1.60

Effective 1/1/2018 — $1.65

Effective 1/1/2019 — $1.70

Effective 1/1/2020 — $1.75

The risk of this multi-employer plan is different from single-employer plans in the following aspects:


1.	Assets contributed to the multi-employer plan by one employer may be used to provide benefits to employees of other participating employers.


2.	If a participating employer stops contributing to the plan, the unfunded obligations of the plan may be borne by the remaining participating employers.


3.	If the Company chooses to stop participating in the multi-employer plan, the Company may be required to pay the plan an amount based on the underfunded status of the plan, referred to as a withdrawal liability.

The following table summarizes the multi-employer plan to which the Company contributes:



		Pension Protection Act Zone Status										Expiration Date of Collective- Bargaining Agreement
				FIP/RP Status Pending/ Implemented	Contributions of the Company
	EIN/Pension Plan Number				Contributions of the Company						Surcharge Imposed
Pension Fund	EIN/Pension Plan Number	2015	2016		2014		2015		2016		Surcharge Imposed
IAM National Pension Fund	51-60321295	Green	Green	No	$	33.1	$	29.8	$	26.9	No	IAM June 27, 2020 UAW November 30, 2020
Pension Fund	Year Company Contributions to Plan Exceeded More Than 5 Percent of Total Contributions (as of December 31 of the Plan's Year-End)
IAM National Pension Fund	2014, 2015, 2016

Defined Contribution Plans

The Company contributes to a defined contribution plan available to all U.S. employees, excluding IAM and UAW represented employees. Under the plan, the Company makes a matching contribution of 75% of the employee contribution to a maximum 8% of eligible individual employee compensation. In addition, non-matching contributions based on an employee's age and years of service are paid at the end of each calendar year for certain employee groups.

The Company recorded $33.8, $34.1 and $36.0 in contributions to these plans for the twelve months ended December 31, 2016, 2015 and 2014, respectively.

On April 1, 2006, as part of the acquisition of BAE Aerostructures, the Company established a defined contribution pension plan for those employees who are hired after the date of acquisition. Under the plan, the Company contributes 8% of base salary while participating employees are required to contribute 4% of base salary. The Company recorded $3.8 in contributions to this plan for the period ended December 31, 2016, $7.0 in contributions for the period ended December 31, 2015 and $7.0 in contributions for the period ended December 31, 2014.

Defined Benefit Pension Plans

Effective June 17, 2005, pension assets and liabilities were spun-off from three Boeing qualified plans into four qualified Spirit AeroSystems plans for each Spirit employee who did not retire from Boeing by August 1, 2005. Effective December 31, 2005, all four qualified plans were merged together. In addition, Spirit has one nonqualified plan providing supplemental benefits to executives (SERP) who transferred from a Boeing nonqualified plan to a Spirit AeroSystems plan and elected to keep their benefits in this plan. Both plans are frozen as of the date of the Boeing Acquisition (i.e., no future service benefits are being earned in these plans). The Company intends to fund its qualified pension plan through a trust. Pension assets are placed in trust solely for the benefit of the pension plans' participants and are structured to maintain liquidity that is sufficient to pay benefit obligations.

On April 1, 2006, as part of the acquisition of BAE Aerostructures, the Company established a defined benefit pension plan for those employees that had pension benefits remaining in BAE Systems' pension plan. In accordance with U.K. legislation, the plan and its assets are managed by an independent trustee company. The investment strategy adopted by this trustee is documented in a Statement of Investment Principles in line with U.K. legislation. The principles for the investment strategy are to maximize the long-term rate of return on plan assets within an acceptable level of risk while maintaining adequate funding levels. The trustee has invested the plan assets in pooled arrangements with authorized investment companies which were selected to be consistent with the plan's overall investment principles and strategy. Effective December 31, 2013, the U.K. pension plan was closed and benefits were frozen and thereafter subject only to statutory pension revaluation.

Other Post-Retirement Benefit Plans

The Company also has post-retirement health care coverage for eligible U.S. retirees and qualifying dependents prior to age 65. Eligibility for employer-provided benefits is limited to those employees who were employed at the date of the Boeing Acquisition and retire on or after attainment of age 62 and 10 years of service. Employees who do not satisfy these eligibility requirements can retire with post-retirement medical benefits at age 55 and 10 years of service, but they must pay the full cost of medical benefits provided.

Obligations and Funded Status

The following tables reconcile the funded status of both pension and post-retirement medical benefits to the balance on the consolidated balance sheets for the fiscal years 2016 and 2015. Benefit obligation balances presented in the tables reflect the projected benefit obligation (PBO) and accumulated benefit obligation (ABO) for the Company's pension plans, and accumulated post-retirement benefit obligations (APBO) for the Company's post-retirement medical plan. The Company uses an end of fiscal year measurement date of December 31 for the Company's U.S. pension and post-retirement medical plans.



	Pension Benefits						Other Post-Retirement Benefits
	Periods Ended December 31,						Periods Ended December 31,
U.S. Plans	2016			2015			2016			2015
Change in projected benefit obligation:
Beginning balance	$	1,011.1		$	1,124.4		$	73.3		$	77.5
Service cost	—			—			1.8			2.2
Employee contributions	—			—			0.8			0.5
Interest cost	42.8			44.4			2.1			2.2
Actuarial losses (gains)	12.9			(113.5		)	(16.7		)	(6.1		)
Special Termination Benefits	23.6			—			3.1			—
Plan Amendments	—			—			(7.2		)	—
Benefits paid	(54.4		)	(44.2		)	(5.7		)	(3.0		)
Projected benefit obligation at the end of the period	$	1,036.0		$	1,011.1		$	51.5		$	73.3
Assumptions used to determine benefit obligation:
Discount rate	4.15		%	4.38		%	3.21		%	3.43		%
Rate of compensation increase	N/A			N/A			N/A			N/A
Medical assumptions:
Trend assumed for the year	N/A			N/A			6.93		%	7.27		%
Ultimate trend rate	N/A			N/A			4.50		%	4.50		%
Year that ultimate trend rate is reached	N/A			N/A			2038			2038
Change in fair value of plan assets:
Beginning balance	$	1,243.2		$	1,310.9		$	—		$	—
Actual return (loss) on assets	114.1			(23.6		)	—			—
Employer contributions to plan	—			0.1			4.9			2.5
Employee contributions to plan	—			—			0.8			0.5
Benefits paid	(54.4		)	(44.2		)	(5.7		)	(3.0		)
Expenses paid	—			—			—			—
Ending balance	$	1,302.9		$	1,243.2		$	—		$	—
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	$	266.8		$	232.1		$	(51.5	)	$	(73.3	)
Net amounts recognized	$	266.8		$	232.1		$	(51.5	)	$	(73.3	)
Amounts recognized in the balance sheet:
Noncurrent assets	$	268.1		$	233.3		$	—		$	—
Current liabilities	—			(0.1		)	(8.9		)	(6.8		)
Noncurrent liabilities	(1.3		)	(1.1		)	(42.6		)	(66.5		)
Net amounts recognized	$	266.8		$	232.1		$	(51.5	)	$	(73.3	)
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated other comprehensive (loss) income	$	(114.4	)	$	(146.2	)	$	32.5		$	9.5
Cumulative employer contributions in excess of net periodic benefit cost	381.2			378.3			(84.0		)	(82.8		)
Net amount recognized in the balance sheet	$	266.8		$	232.1		$	(51.5	)	$	(73.3	)
Information for pension plans with benefit obligations in excess of plan assets:
Projected benefit obligation/APBO	$	1.2		$	1.2		$	51.5		$	73.3
Accumulated benefit obligation	1.2			1.2			—			—



	Pension Benefits
	Periods Ended December 31,
U.K. Plans	2016			2015
Change in projected benefit obligation:
Beginning balance	$	82.8		$	89.1
Service cost	1.0			1.2
Interest cost	2.9			3.3
Actuarial losses (gains)	17.4			(3.2		)
Benefits paid	(0.8		)	(1.6		)
Expense paid	(1.0		)	(1.2		)
Plan settlements	(5.5		)	—
Exchange rate changes	(14.7		)	(4.8		)
Projected benefit obligation at the end of the period	$	82.1		$	82.8
Assumptions used to determine benefit obligation:
Discount rate	2.70		%	4.00		%
Rate of compensation increase	3.20		%	3.10		%
Change in fair value of plan assets:
Beginning balance	$	96.4		$	104.7
Actual return (loss) on assets	25.3			(0.1		)
Company contributions	—			0.1
Plan settlements	(6.5		)	—
Expenses paid	(1.0		)	(1.1		)
Benefits paid	(0.8		)	(1.6		)
Exchange rate changes	(17.2		)	(5.6		)
Ending balance	$	96.2		$	96.4
Reconciliation of funded status to net amounts recognized:
Funded status	14.2			13.6
Net amounts recognized	$	14.2		$	13.6
Amounts recognized in the balance sheet:
Noncurrent assets	$	14.2		$	13.6
Net amounts recognized	$	14.2		$	13.6
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated other comprehensive loss	(0.2		)	(3.9		)
Prepaid pension cost	14.4			17.5
Net amount recognized in the balance sheet	$	14.2		$	13.6
Information for pension plans with benefit obligations in excess of plan assets:
Projected benefit obligation/APBO	$	—		$	—
Accumulated benefit obligation	—			—
Fair value of assets	$	—		$	—

Annual Expense

The components of pension and other post-retirement benefit plans expense for the U.S. plans and the assumptions used to determine benefit obligations for each of the periods ended December 31, 2016, 2015 and 2014 are as follows:



	Pension Benefits									Other Post-Retirement Benefits
	Periods Ended December 31,									Periods Ended December 31,
U.S. Plans	2016			2015			2014			2016			2015			2014
Components of net periodic benefit cost (income):
Service cost	$	—		$	—		$	—		$	1.8		$	2.2		$	2.3
Interest cost	42.7			44.4			45.9			2.1			2.2			2.7
Expected return on plan assets	(74.9		)	(78.1		)	(76.1		)	—			—			—
Amortization of net loss	5.7			3.7			—			—			—			—
Amortization of prior service costs	—			—			—			(0.9		)	—			—
Special Termination Benefits	23.6			—			1.7			3.1			—			1.7
Net periodic benefit (income) cost	(2.9		)	(30.0		)	(28.5		)	6.1			4.4			6.7
Other changes recognized in OCI:
Total recognized in OCI (income) loss	$	(31.8	)	$	(15.5	)	$	72.0		$	(23.0	)	$	(6.1	)	$	0.8
Total recognized in net periodic benefit cost and OCI	$	(34.7	)	$	(45.5	)	$	43.5		$	(16.9	)	$	(1.7	)	$	7.5
Assumptions used to determine net periodic benefit costs:
Discount rate	4.38		%	3.99		%	4.89		%	3.43		%	3.14		%	3.89		%
Expected return on plan assets	6.00		%	6.00		%	6.50		%	N/A			N/A			N/A
Salary increases	N/A			N/A			N/A			N/A			N/A			N/A
Medical Assumptions:
Trend assumed for the year	N/A			N/A			N/A			7.27		%	7.62		%	8.50		%
Ultimate trend rate	N/A			N/A			N/A			4.50		%	4.50		%	4.50		%
Year that ultimate trend rate is reached	N/A			N/A			N/A			2038			2030			2030

The estimated net gain that will be amortized from other comprehensive income into net periodic benefit cost over the next fiscal year is zero for Pension Benefits and $2.2 for Other Post-Retirement Benefits plans.

The components of the pension benefit plan expense for the U.K. plans and the assumptions used to determine benefit obligations for each of the periods ended December 31, 2016, 2015 and 2014 are as follows:



	Pension Benefits
	Periods Ended December 31,
U.K. Plans	2016			2015			2014
Components of net periodic benefit cost (income):
Service cost	$	1.0		$	1.2		$	0.7
Interest cost	2.9			3.3			3.6
Expected return on plan assets	(3.6		)	(4.9		)	(5.7		)
Net periodic benefit income (cost)	$	0.3		$	(0.4	)	$	(1.4	)
Other changes recognized in OCI:
Total (loss) income recognized in OCI	$	(4.6	)	$	1.5		$	6.8
Total recognized in net periodic benefit cost and OCI	$	(4.3	)	$	1.1		$	5.4
Assumptions used to determine net periodic benefit costs:
Discount rate	4.00		%	3.80		%	4.75		%
Expected return on plan assets	4.30		%	4.80		%	5.80		%
Salary increases	3.10		%	3.05		%	3.25		%

The estimated net (gain) loss that will be amortized from other comprehensive income into net periodic benefit cost over the next fiscal year for the U.K. plan is zero.

Assumptions

The Company sets the discount rate assumption annually for each of its retirement-related benefit plans as of the measurement date, based on a review of projected cash flow and a long-term high-quality corporate bond yield curve. The discount rate determined on each measurement date is used to calculate the benefit obligation as of that date, and is also used to calculate the net periodic benefit (income)/cost for the upcoming plan year. During 2015, the mortality assumption for the U.S. plans was updated to Mercer’s MRP-2007 generational mortality tables for non-annuitants and Mercer’s MILES-2010 generational tables for the Auto, Industrial Goods and Transportation group for annuitants both reflecting Mercer’s MMP-2007 improvement scale. In 2016, the Company incorporated the MMP-2016 improvement scale. A blue collar adjustment is reflected for the hourly union participants and a white collar adjustment is reflected for all other participants. Actuarial gains and losses are amortized using the corridor method over the average working lifetimes of active participants/membership.

The pension expected return on assets assumption is derived from the long-term expected returns based on the investment allocation by class specified in the Company's investment policy. The expected return on plan assets determined on each measurement date is used to calculate the net periodic benefit (income)/cost of the upcoming plan year.

Assumed health care cost trend rates have a significant effect on the amounts reported for the health care plans. To determine the health care cost trend rates the Company considers national health trends and adjusts for its specific plan design and locations. The trend and aging assumptions were updated during 2016 to reflect more current trends.

A one-percentage point increase in the initial through ultimate assumed health care trend rates would have increased the accumulated post-retirement benefit obligation by $2.5 at December 31, 2016 and the aggregate service and interest cost components of non-pension post-retirement benefit expense for 2016 by $0.2. A one-percentage point decrease would have decreased the obligation by $2.3 and the aggregate service and interest cost components of non-pension post-retirement benefit expense for 2016 by $0.1.

U.S. Plans

The Company's investment objective is to achieve long-term growth of capital, with exposure to risk set at an appropriate level. This objective shall be accomplished through the utilization of a diversified asset mix consisting of equities (domestic and international) and taxable fixed income securities. The allowable asset allocation range is:



Equities	20 - 50%
Fixed income	50 - 80%
Real estate	0 - 7%

Investment guidelines include that no security, except issues of the U.S. Government, shall comprise more than 5% of total Plan assets and further, no individual portfolio shall hold more than 7% of its assets in the securities of any single entity, except issues of the U.S. Government. The following derivative transactions are prohibited — leverage, unrelated speculation and "exotic" collateralized mortgage obligations or CMOs. Investments in hedge funds, private placements, oil and gas and venture capital must be specifically approved by the Company in advance of their purchase.

The Company's plans have asset allocations for the U.S., as of December 31, 2016 and December 31, 2015, as follows:



	2016		2015
Asset Category — U.S.
Equity securities — U.S.	29	%	29	%
Equity securities — International	4	%	4	%
Debt securities	65	%	65	%
Real estate	2	%	2	%
Total	100	%	100	%

U.K. Plans

The Trustee's investment objective is to ensure that they can meet their obligation to the beneficiaries of the Plan. An additional objective is to achieve a return on the total Plan, which is compatible with the level of risk considered appropriate. The overall benchmark allocation of the Plan's assets is:



Equity securities	35	%
Debt securities	60	%
Property	5	%

The Company's plans have asset allocations for the U.K., as of December 31, 2016 and December 31, 2015, as follows:



	2016		2015
Asset Category — U.K.
Equity securities	24	%	34	%
Debt securities	71	%	60	%
Other	5	%	6	%
Total	100	%	100	%

Projected contributions and benefit payments

Required pension contributions under Employee Retirement Income Security Act (ERISA) regulations are expected to be zero in 2017 and discretionary contributions are not expected in 2017. SERP and post-retirement medical plan contributions in 2017 are not expected to exceed $8.9. Expected contributions to the U.K. plan for 2017 are zero.

The Company monitors its defined benefit pension plan asset investments on a quarterly basis and believes that the Company is not exposed to any significant credit risk in these investments.

The total benefits expected to be paid over the next ten years from the plans' assets or the assets of the Company, by country, are as follows:



U.S.	Pension Plans		Other Post-Retirement Benefit Plans
2017	$	51.3	$	8.9
2018	$	36.3	$	7.6
2019	$	39.9	$	5.9
2020	$	43.4	$	5.2
2021	$	46.8	$	5.0
2022-2026	$	281.3	$	20.8



U.K.	Pension Plans
2017	$	0.8
2018	$	0.8
2019	$	0.8
2020	$	0.8
2021	$	0.9
2022-2026	$	4.6

Fair Value Measurements

The pension plan assets are valued at fair value. A financial instrument's level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The following is a description of the valuation methodologies used for the investments measured at fair value, including the general classification of such instruments pursuant to the valuation hierarchy.

Temporary Cash Investments — These investments consist of U.S. dollars and foreign currencies held in master trust accounts. Foreign currencies held are reported in terms of U.S. dollars based on currency exchange rates readily available in active markets. These temporary cash investments are classified as level 1 investments.

Collective Investment Trusts — These investments are public investment vehicles valued using market prices and performance of the fund. The trust allocates notional units to the policy holder based on the underlying notional unit buy (offer) price using the middle market price plus transaction costs. These investments are classified within level 2 of the valuation hierarchy. In addition, the collective investment trust includes a real estate fund which is classified within level 3 of the valuation hierarchy.

Commingled Equity and Bond Funds — These investments are valued at the closing price reported by the Plan Trustee. These investments are not being traded in an active market, but are backed by various investment securities managed by the Bank of New York. Fair value is being calculated using unobservable inputs that rely on the Bank of New York's own assumptions and are therefore classified within level 2 of the valuation hierarchy, although these assumptions are based on underlying investments which are traded on an active market.

As of December 31, 2016 and December 31, 2015, the pension plan assets measured at fair value on a recurring basis were as follows:



			At December 31, 2016 Using
Description	December 31, 2016 Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Temporary Cash Investments	$	0.2	$	0.2	$	—	$	—
Collective Investment Trusts	96.0		—		91.2		4.8
Commingled Equity and Bond Funds	1,302.9		—		1,302.9		—
	$	1,399.1	$	0.2	$	1,394.1	$	4.8



			At December 31, 2015 Using
Description	December 31, 2015 Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Temporary Cash Investments	$	0.6	$	0.6	$	—	$	—
Collective Investment Trusts	95.8		—		90.2		5.6
Commingled Equity and Bond Funds	1,243.2		—		1,243.2		—
	$	1,339.6	$	0.6	$	1,333.4	$	5.6

The table below sets forth a summary of changes in the fair value of the Plan's level 3 investment assets and liabilities for the years ended December 31, 2016 and December 31, 2015:



	December 31, 2016
Description	Beginning Fair Value		Purchases		Gain (Loss)		Sales, Maturities, Settlements, Net		Exchange rate			Ending Fair Value
Collective Investment Trusts	$	5.6	$	—	$	0.1	$	—	$	(0.9	)	$	4.8
	$	5.6	$	—	$	0.1	$	—	$	(0.9	)	$	4.8



	December 31, 2015
Description	Beginning Fair Value		Purchases		Gain (Loss)		Sales, Maturities, Settlements, Net		Exchange rate			Ending Fair Value
Collective Investment Trusts	$	5.3	$	—	$	0.6	$	—	$	(0.3	)	$	5.6
	$	5.3	$	—	$	0.6	$	—	$	(0.3	)	$	5.6

Defined Contribution Plans

The Company contributes to a defined contribution plan available to all U.S. employees, excluding IAM and UAW represented employees. Under the plan, the Company makes a matching contribution of 75% of the employee contribution to a maximum 8% of eligible individual employee compensation. In addition, non-matching contributions based on an employee's age and years of service are paid at the end of each calendar year for certain employee groups.

The Company recorded $33.8, $34.1 and $36.0 in contributions to these plans for the twelve months ended December 31, 2016, 2015 and 2014, respectively.

On April 1, 2006, as part of the acquisition of BAE Aerostructures, the Company established a defined contribution pension plan for those employees who are hired after the date of acquisition. Under the plan, the Company contributes 8% of base salary while participating employees are required to contribute 4% of base salary. The Company recorded $3.8 in contributions to this plan for the period ended December 31, 2016, $7.0 in contributions for the period ended December 31, 2015 and $7.0 in contributions for the period ended December 31, 2014.

Defined Benefit Pension Plans

Effective June 17, 2005, pension assets and liabilities were spun-off from three Boeing qualified plans into four qualified Spirit AeroSystems plans for each Spirit employee who did not retire from Boeing by August 1, 2005. Effective December 31, 2005, all four qualified plans were merged together. In addition, Spirit has one nonqualified plan providing supplemental benefits to executives (SERP) who transferred from a Boeing nonqualified plan to a Spirit AeroSystems plan and elected to keep their benefits in this plan. Both plans are frozen as of the date of the Boeing Acquisition (i.e., no future service benefits are being earned in these plans). The Company intends to fund its qualified pension plan through a trust. Pension assets are placed in trust solely for the benefit of the pension plans' participants and are structured to maintain liquidity that is sufficient to pay benefit obligations.

On April 1, 2006, as part of the acquisition of BAE Aerostructures, the Company established a defined benefit pension plan for those employees that had pension benefits remaining in BAE Systems' pension plan. In accordance with U.K. legislation, the plan and its assets are managed by an independent trustee company. The investment strategy adopted by this trustee is documented in a Statement of Investment Principles in line with U.K. legislation. The principles for the investment strategy are to maximize the long-term rate of return on plan assets within an acceptable level of risk while maintaining adequate funding levels. The trustee has invested the plan assets in pooled arrangements with authorized investment companies which were selected to be consistent with the plan's overall investment principles and strategy. Effective December 31, 2013, the U.K. pension plan was closed and benefits were frozen and thereafter subject only to statutory pension revaluation

Capital Stock	12 Months Ended
Capital Stock	Dec. 31, 2016
Class of Stock Disclosures [Abstract]
Capital Stock	Capital Stock Holdings has authorized 360,000,000 shares of stock. Of that, 200,000,000 shares are class A common stock, par value $0.01 per share, one vote per share, 150,000,000 shares are class B common stock, par value $0.01 per share, one vote per share and 10,000,000 shares are preferred stock, par value $0.01 per share. In March, June and August 2014, certain selling stockholders sold 22,915,300 shares of the Company's class A common stock at prices to the public ranging from $28.62 to $35.90 per share in secondary offerings of the Company's class A common stock. Following the August offering, Onex no longer held any investment in the Company. In association with the Boeing Acquisition, Spirit executives with balances in Boeing's Supplemental Executive Retirement Plan (SERP) were authorized to purchase a fixed number of units of Holdings "phantom stock" at $3.33 per unit based on the present value of their SERP balances. Under this arrangement, 860,244 phantom units were purchased. Any payment on account of units may be made in cash or shares of common stock at the sole discretion of Holdings. The balance of SERP units was 64,170 and 94,143 as of December 31, 2016 and December 31, 2015, respectively. Repurchases of Common Stock During the period ended December 31, 2015, the Company repurchased 5.7 million shares of its class A common stock for $300.0. During the period ended December 31, 2016, the Company repurchased 14.2 million shares of its class A common stock for $649.6.

Stock Compensation

12 Months Ended

Dec. 31, 2016

Share-based Compensation [Abstract]

Stock Compensation

Holdings has established various stock compensation plans which include restricted share grants and stock purchase plans. Compensation values are based on the value of Holdings' common stock at the grant date. The common stock value is added to equity and charged to period expense or included in inventory and cost of sales.

On April 30, 2014, the Company’s Board of Directors approved an Omnibus Incentive Plan (the "Omnibus Plan"), which replaces the Executive Incentive Plan, Short-Term Incentive Plan, Long-Term Incentive Plan and Director Stock Plan (collectively referred to as "Prior Plans"). No new awards will be granted under the Prior Plans. Outstanding awards under the Prior Plans will continue to be governed by the terms of such plans until exercised, expired, or otherwise terminated or canceled. The adoption of the Omnibus Plan was non-dilutive to the Company's stockholders.

For the fiscal period ended December 31, 2016, Holdings has recognized a net total of $42.5 of stock compensation expense. The entire $42.5 of net stock compensation expense recorded in 2016 was charged directly to selling, general and administrative expense. Holdings recognized a total of $26.0 and $16.4 of stock compensation expense for the periods ended December 31, 2015 and December 31, 2014, respectively.

Executive Incentive Plan

The Company's Executive Incentive Plan, or EIP, was designed to provide participants with the opportunity to acquire an equity interest in the Company through direct purchase of shares of the Company's class B common stock at prices established by the Board of Directors or through grants of class B restricted common stock with performance based vesting.

Prior to 2014, the Company had issued restricted shares as part of the Company's EIP. The restricted shares were granted in groups of four shares. Participants do not have the unrestricted rights of stockholders until those shares vest. The shares may vest upon a liquidity event, with the number of shares vested based upon a participant's number of years of service to the Company, the portion of the investment by Onex and its affiliates liquidated through the date of the liquidity event and the return on invested capital by Onex and its affiliates through the date of the liquidity event. If a specific type of liquidity event has not occurred by the 10th year, shares may vest based on a valuation of the Company.

The Company's initial public offering in November 2006 (the "IPO") and secondary offerings in May 2007, April 2011 and March, June and August 2014 were considered liquidity events under the EIP. In the August 2014 secondary offering, Onex sold 100% of its remaining investment in the Company and as a result all remaining EIP shares vested upon the liquidity event. Subsequent to the liquidity event, the Company no longer awards shares under this plan.

The following table summarizes the activity of restricted shares under the EIP for the periods ended December 31, 2016, 2015 and 2014:



	Shares		Value⁽¹⁾
	(Thousands)
Executive Incentive Plan
Nonvested at December 31, 2013	869		$	9.8
Vested during period	(869	)	(9.8		)
Forfeited during period	—		—
Nonvested at December 31, 2014	—		—
Vested during period	—		—
Forfeited during period	—		—
Nonvested at December 31, 2015	—		—
Vested during period	—		—
Forfeited during period	—		—
Nonvested at December 31, 2016	—		$	—

_______________________________________


(1)	Value represents grant date fair value.

Board of Directors Stock Awards

The Company's Director Stock Plan provided non-employee directors the opportunity to receive grants of restricted shares of class A common stock, or Restricted Stock Units (RSUs) or a combination of both common stock and RSUs. The class A common stock grants and RSU grants vest one year from the grant date. The RSU grants are payable upon the director's separation from service. The Board of Directors or its authorized committee were authorized to make discretionary grants of shares or RSUs from time to time. Since the adoption of the Omnibus Plan in April 2014, grants of equity to directors are made under the Omnibus Plan instead of the Director Stock Plan.

For each non-employee director of the Company, at least one-half of their annual director compensation is required to be paid in the form of a grant of class A common stock and/or RSUs, as elected by each director. In addition, each director may elect to have all or any portion of the remainder of their annual director compensation paid in cash or in the form of a grant of class A stock and/or RSUs. If participants cease to serve as directors within a year of the grant, the restricted shares and/or RSUs are forfeited. In 2016, the Board of Directors authorized a grant of 26,480 shares of restricted class A common stock, valued at $1.2 based on the share price of the Company's common stock at the grant dates. Additionally, 14,372 shares of class A common stock, including 6,568 Restricted Stock Units, with an aggregate grant date fair value of $0.7 awarded under the Company's Director Stock Plan vested during the twelve months ended December 31, 2016. The Company expensed a net amount of $1.2 for the Board of Directors shares for the period ended December 31, 2016. The Company expensed $1.1 and $0.9 for the periods ended December 31, 2015 and December 31, 2014, respectively. The Company's unamortized stock compensation related to these restricted shares is $0.5 which will be recognized over a weighted average remaining period of 5 months. The intrinsic value of the unvested shares based on the value of the Company's stock at December 31, 2016 was $1.5, based on the value of the Company's stock and the number of unvested shares.

The following table summarizes stock and RSU grants to members of the Company's Board of Directors for the periods ended December 31, 2016, 2015 and 2014:



	Shares			Value⁽¹⁾
	Class A		Class B	Class A			Class B
	(Thousands)
Board of Directors Stock Grants
Nonvested at December 31, 2013	39		—	$	0.9		$	—
Granted during period	32		—	1.1			—
Vested during period	(37	)	—	(0.8		)	—
Forfeited during period	(4	)	—	(0.1		)	—
Nonvested at December 31, 2014	30		—	1.1			—
Granted during period	21		—	1.1			—
Vested during period	(27	)	—	(1.0		)	—
Forfeited during period	(3	)	—	(0.1		)	—
Nonvested at December 31, 2015	21		—	1.1			—
Granted during period	26		—	1.2			—
Vested during period	(21	)	—	(1.1		)	—
Forfeited during period	—		—	—			—
Nonvested at December 31, 2016	26		—	$	1.2		$	—

_______________________________________


(1)	Value represents grant date fair value.

Short-Term Incentive Plan

The Short-Term Incentive Program under the Omnibus Plan enables eligible employees to receive incentive benefits in the form of restricted stock in the Company, cash, or both, as determined by the Board of Directors or its authorized committee. Effective in the first quarter of 2014, the Company made the determination to pay its short term incentive awards, which are based on Company performance, 100% in cash.

The following table summarizes the activity of the restricted shares under the STIP for the twelve months ended December 31, 2016, 2015 and 2014:



	Shares		Value⁽¹⁾
	(Thousands)
Short-Term Incentive Plan
Nonvested at December 31, 2013	62		$	1.0
Granted during period	—		—
Vested during period	(62	)	(1.0		)
Forfeited during period	—		—
Nonvested at December 31, 2014	—		—
Granted during period	—		—
Vested during period	—		—
Forfeited during period	—		—
Nonvested at December 31, 2015	—		—
Granted during period	—		—
Vested during period	—		—
Forfeited during period	—		—
Nonvested at December 31, 2016	—		$	—

_______________________________________


(1)	Value represents grant date fair value.

Long-Term Incentive Awards

The Fourth Amended and Restated Long-Term Incentive Plan ("LTIP") was designed to encourage retention of key employees, and awards were made under the LTIP for this purpose prior to the adoption of the Omnibus Plan.

The Omnibus Plan approved on April 30, 2014 includes a Long-Term Incentive Award (LTIA) for the 2014 plan year and forward. The awards are based on the new LTIA design that provide both time and performance based incentives.

•75% of the LTIA is service-based restricted stock that will vest in equal installments over a three-year period.


•	25% of the LTIA is market-based restricted stock that will vest on the third-year anniversary of the grant date contingent upon total shareholder return (TSR) compared to a group of the Company’s peers.

For the twelve months ended December 31, 2016, 623,620 shares of class A common stock with an aggregate grant date fair value of $27.4 were granted under the service-based portion of the Company's LTIA. In addition, 206,132 shares of class A common stock with an aggregate grant date fair value of $10.9 were granted under the market-based portion of the Company's LTIA under the Omnibus Plan and such shares are eligible to vest on the three-year anniversary of the grant date depending on total shareholder return compared to a group of the Company's peers. Additionally, 503,543 shares of class A common stock with an aggregate grant date fair value of $14.9 awarded under the Company's LTIP and LTIA vested during the twelve months ended December 31, 2016.

During the quarter ended December 31, 2015, 2,829 shares of class A common stock with an aggregate grant date fair value of $0.2 were granted under the service-based portion of the Company's LTIA.

For the twelve months ended December 31, 2015, 535,648 shares of class A common stock with an aggregate grant date fair value of $26.6 were granted under the service-based portion of the Company's LTIA . In addition, 96,423 shares of class A common stock with an aggregate grant date fair value of $6.2 were granted under the market-based portion of the Company's LTIA under the Omnibus Plan and such shares are eligible to vest on the three-year anniversary of the grant date depending on total shareholder return compared to a group of the Company's peers. Additionally, 878,706 shares of class A common stock with an aggregate grant date fair value of $21.6 awarded under the Company's LTIP vested during the twelve months ended 2015.

During the quarter ended December 31, 2014, 7,314 shares of class A common stock with an aggregate grant date fair value of $0.3 were granted under the service-based portion of the Company's LTIA. In addition, 600 shares of class A common stock with an aggregate grant date fair value of less than $0.1 were granted under the market-based portion of the Company's LTIA.

For the twelve months ended December 31, 2014, the Board of Directors approved grants of 564,509 shares of class A common stock with an aggregate grant date fair value of $19.0 under the service-based portion of the Company's LTIA under the Omnibus Plan and such shares will vest annually in three equal installments beginning on the one-year anniversary of the grant date. Additionally, 125,212 shares of class A common stock with an aggregate grant date fair value of $5.6 were granted under the market-based portion of the Company's LTIA under the Omnibus Plan and such shares are eligible to vest on the three-year anniversary of the grant date depending on the total shareholder return compared to a group of the Company's peers. Additionally, 547,982 shares of class A common stock with an aggregate grant date fair value of $12.5 awarded under the Company's LTIP vested during 2014.

The Company expensed a net total of $41.3 for the unvested class A LTIP and LTIA shares in the twelve months ended December 31, 2016. The Company expensed a net total of $24.9 and $15.4 for class A LTIP and LTIA shares for the twelve month periods ended December 31, 2015 and December 31, 2014, respectively.

The Company's unamortized stock compensation related to these unvested class A shares is $32.3 which will be recognized over a weighted average remaining period of 1.6 years. The intrinsic value of the unvested class A LTIA shares at December 31, 2016 was $90.6, based on the value of the Company's common stock and the number of unvested shares.

The following table summarizes the activity of the restricted shares under the LTIP and LTIA for the twelve month periods ended December 31, 2016, 2015 and 2014:



	Shares			Value⁽¹⁾
	Class A		Class B	Class A			Class B
	(Thousands)
Long-Term Incentive Plan/Long-Term Incentive Award under Omnibus Plan
Nonvested at December 31, 2013	2,358		—	$	52.3		$	—
Granted during period	690		—	24.6			—
Vested during period	(548	)	—	(12.5		)	—
Forfeited during period	(245	)	—	(6.1		)	—
Nonvested at December 31, 2014	2,255		—	58.3			—
Granted during period	632		—	32.8			—
Vested during period	(879	)	—	(21.6		)	—
Forfeited during period	(171	)	—	(5.1		)	—
Nonvested at December 31, 2015	1,837		—	64.4			—
Granted during period	830		—	38.3			—
Vested during period	(830	)	—	(24.5		)	—
Forfeited during period	(280	)	—	(10.9		)	—
Nonvested at December 31, 2016	1,557		—	$	67.3		$	—

_______________________________________


(1)	Value represents grant date fair value.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Income Taxes

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

The following summarizes pretax income:



	2016		2015		2014
U.S.	$	593.3	$	739.4	$	194.2
International	67.2		68.7		68.2
Total (before equity earnings)	$	660.5	$	808.1	$	262.4

The tax provision contains the following components:



	2016			2015			2014
Current
Federal	$	158.0		$	175.5		$	(91.0	)
State	3.6			3.5			(0.9		)
Foreign	29.2			5.5			4.0
Total current	$	190.8		$	184.5		$	(87.9	)
Deferred
Federal	$	20.0		$	(119.1	)	$	—
State	(1.0		)	(48.9		)	(2.0		)
Foreign	(17.7		)	4.1			(6.0		)
Total deferred	1.3			(163.9		)	(8.0		)
Total tax provision (benefit)	$	192.1		$	20.6		$	(95.9	)

The income tax provision from operations differs from the tax provision computed at the U.S. federal statutory income tax rate due to the following:



	2016					2015					2014
Tax at U.S. Federal statutory rate	$	231.2		35.0	%	$	283.3		35.0	%	$	91.8		35.0	%
State income taxes, net of Federal benefit	11.6			1.8		15.0			1.9		4.1			1.6
State income tax credits, net of Federal benefit	(9.4		)	(1.4	)	(4.1		)	(0.5	)	(9.0		)	(3.4	)
Foreign rate differences	(13.5		)	(2.0	)	(13.5		)	(1.7	)	(12.3		)	(4.7	)
Research and Experimentation	(3.6		)	0.6		(3.3		)	(0.4	)	(3.0		)	(1.1	)
Domestic Production Activities Deduction	(16.4		)	(2.5	)	(17.8		)	(2.2	)	—			—
Interest on assessments	0.6			0.1		(1.0		)	(0.1	)	(3.7		)	(1.4	)
Excess tax benefits	(4.6		)	(0.7	)	—			—		—			—
Valuation Allowance - U.S. Deferred Tax Asset	—			—		(241.9		)	(29.9	)	(167.2		)	(63.7	)
Other	(3.8		)	(0.6	)	3.9			0.5		3.4			1.2
Total provision (benefit) for income taxes	$	192.1		29.1	%	$	20.6		2.6	%	$	(95.9	)	(36.5	)%

Significant tax effected temporary differences comprising the net deferred tax asset are as follows:



	2016			2015
Long-term contracts	$	127.7		$	142.4
Post-retirement benefits other than pensions	19.1			27.2
Pension and other employee benefit plans	(77.5		)	(64.4		)
Employee compensation accruals	68.0			52.6
Depreciation and amortization	(154.4		)	(124.6		)
Inventory	1.7			2.1
Interest swap contracts	—			—
State income tax credits	71.7			70.5
Accruals and reserves	91.7			85.8
Deferred production	(3.7		)	(2.4		)
Deferred gain — severe weather event	—			(21.2		)
Net operating loss carryforward	3.7			0.6
Other	(5.7		)	(3.8		)
Net deferred tax asset	142.3			164.8
Valuation allowance	(13.6		)	(15.1		)
Net deferred tax asset	$	128.7		$	149.7

Deferred tax detail above is included in the consolidated balance sheet and supplemental information as follows:



	2016			2015
Non-current deferred tax assets	128.8			162.8
Non-current deferred tax liabilities	(0.1		)	(13.1		)
Net non-current deferred tax assets	$	128.7		$	149.7
Total deferred tax asset	$	128.7		$	149.7

The following is a roll forward of the deferred tax valuation allowance at December 31, 2016, 2015 and 2014:



Deferred Tax Asset Valuation Allowance	2016			2015			2014
Balance, January 1	$	15.1		$	257.3		$	396.5
US deferred tax asset	—			(109.3		)	40.4
Income tax credits	(0.9		)	(57.4		)	9.1
Depreciation and amortization	(0.1		)	119.6			16.3
Long-term contracts	—			(194.6		)	(205.0		)
Other	(0.6		)	(0.5		)	—
Balance, December 31	$	13.5		$	15.1		$	257.3

A valuation allowance, if needed, reduces deferred tax assets to the amount expected to be realized. When determining the amount of net deferred tax assets that are more likely than not to be realized, we assess all available positive and negative evidence. The weight given to the positive and negative evidence is commensurate with the extent the evidence may be objectively verified.

The Company continues to maintain $13.5 in valuation allowances primarily against separate company state income tax credit deferred tax assets.

We consider the earnings of all non-US subsidiaries to be indefinitely invested outside the United States on the basis of estimates that future domestic cash generation will be sufficient to meet future domestic cash needs and our specific plans for reinvestment of those subsidiary earnings. We have not recorded a deferred tax liability of approximately $100.0 related to the U.S. federal and state income taxes and foreign withholding taxes on approximately $290.0 of undistributed earnings of foreign subsidiaries indefinitely invested outside the United States. Should we decide to repatriate the foreign earnings, we would need to adjust our income tax provision in the period we determined that the earnings will no longer be indefinitely invested outside the United States.

The beginning and ending unrecognized tax benefits reconciliation is as follows:



	2016		2015		2014
Beginning balance	$	6.2	$	5.9	$	18.4
Gross increases related to current period tax positions	—		—		—
Gross increases related to prior period tax positions	0.1		0.3		0.9
Gross decreases related to prior period tax positions	—		—		(13.4		)
Statute of limitations' expiration	—		—		—
Settlements	—		—		—
Ending balance	$	6.3	$	6.2	$	5.9

Included in the December 31, 2016 balance was $4.1 in unrecognized tax benefits which, if ultimately recognized, will reduce the Company's effective tax rate. The Internal Revenue Service's examination of the Company's 2015 U.S. Federal income tax return is substantially complete. The Company will continue to participate in the Compliance Assurance Process ("CAP") program for its 2016 and 2017 tax years. The CAP program's objective is to resolve issues in a timely, contemporaneous manner and eliminate the need for a lengthy post-filing examination. The HM Revenue & Customs completed its examination of the Company's 2009-2011 U.K. income tax returns and the statute of limitations has lapsed on the 2013 tax return. The Directorate General of Public Finance closed its examination of the Company's 2011-2013 France income tax returns. While a change could result from the ongoing examinations, the Company expects no material change in its recorded unrecognized tax liability in the next 12 months.

The Company reports interest and penalties, if any, related to unrecognized tax benefits in the income tax provision. As of December 31, 2016, and December 31, 2015, there was no accrued interest on the unrecognized tax benefit liability included in the consolidated balance sheets and there was no impact of interest on the Company’s unrecognized tax benefit liability during 2016 and 2015.

As a result of the early adoption of ASU 2016-09, during the twelve months ended December 31, 2016, share-based compensation excess tax benefits of $4.6 were reflected in the Consolidated Statements of Income as a component of the income tax provision and the Consolidated Statement of Cash Flows included a $4.6 increase to net cash provided by operating activities. Accounting guidance requires that this item is treated as a discrete adjustment to our tax rate, which is reflected in the 29.1% effective tax rate for the twelve months ended December 31, 2016.

The Company continues to operate under a tax holiday in Malaysia effective through September 2024. In 2014, the Company received formal approval of the tax holiday from the Malaysian tax authorities, with conditional renewals once every five years beginning in September 2014. The Company expects to meet the requirements for the conditional renewals. The Company’s 2016 income tax expense reflects $6.6 of Malaysia tax holiday benefit for the year ended December 31, 2016.

At December 31, 2016, the Company had total North Carolina state net operating loss carryforwards of $17.0 which begin to expire in 2026.

On December 18, 2015, the President signed legislation making permanent the U.S. Research Tax Credit so that it applies for amounts paid or accrued on or after January 1, 2015. The Company's income tax expense for 2016 reflects the benefit of the Research Tax Credit attributable to 2016 of $3.6.

Included in the deferred tax assets at December 31, 2016 are $48.1 in Kansas High Performance Incentive Program ("HPIP") Credit, $8.2 in Kansas Research & Development ("R&D") Credit, and $2.7 in Kansas Business and Jobs Development Credit, totaling $59.0 in gross Kansas state income tax credit carryforwards, net of federal benefit. The HPIP Credit provides a 10% investment tax credit for qualified business facilities located in Kansas for which $3.6 expires in 2027, $9.7 expires in 2028, $11.7 expires in 2029, $8.9 expires in 2030, $5.3 expires in 2031, and the remainder expires in 2032. The R&D Credit provides a credit for qualified research and development expenditures conducted within Kansas. This credit can be carried forward indefinitely. The Business and Jobs Development Credit provides a tax credit for increased employment in Kansas. This credit can be carried forward indefinitely.

Included in the deferred tax assets at December 31, 2016 are $5.5 in North Carolina Investing in Business Property Credit, $3.9 in North Carolina Investment in Real Property Credit, and $3.2 in North Carolina Creating Jobs Credit, totaling $12.6 in gross North Carolina state income tax credit carryforwards, net of federal benefit. The Investing in Business Property Credit provides a 7% investment tax credit for property located in a North Carolina development area and the Investment in Real Property Credit provides a 30% investment tax credit for real property located in a North Carolina development area. The Creating Jobs Credit provides a tax credit for increased employment in North Carolina. These North Carolina state income tax credits can be carried forward 20 years. It is management's opinion that none of these North Carolina state income tax credits will be utilized before they expire and a $12.6 valuation allowance is recorded against the deferred tax asset, net of federal benefit.

The Company had $7.4 and $6.8 of income tax receivable as of December 31, 2016 and December 31, 2015, respectively, which is reflected within other current assets on the Consolidated Balance Sheet.

Equity

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Equity

Earnings per Share Calculation

Basic net income per share is computed using the weighted-average number of outstanding shares of common stock during the measurement period. Diluted net income per share is computed using the weighted-average number of outstanding shares of common stock and, when dilutive, potential outstanding shares of common stock during the measurement period.

Subject to preferences that may apply to shares of preferred stock outstanding at the time, holders of the Company’s outstanding common stock are entitled to any dividend declared by the Board of Directors out of funds legally available for this purpose. The Company did not pay any cash dividends in the period ended December 31, 2016. On November 1, 2016 the Company announced that its Board of Directors declared a $0.10 per share quarterly cash dividend on the outstanding common stock of the Company which totaled $12.0 and was paid on January 9, 2017 to shareholders of record at the close of business on December 19, 2016. Any future determination to continue to pay dividends will be at the discretion of the Company's Board of Directors and will depend upon, among other factors, the Company's results of operations, financial condition, capital requirements and contractual restrictions, including the requirements of financing agreements to which the Company is party. The Company accounts for treasury stock under the cost method and includes treasury stock as a component of stockholders’ equity. As of December 31, 2016, no treasury shares have been reissued or retired.

The following table sets forth the computation of basic and diluted earnings per share:



	For the Twelve Months Ended
	December 31, 2016					December 31, 2015					December 31, 2014
	Income		Shares	Per Share Amount		Income		Shares	Per Share Amount		Loss		Shares	Per Share Amount
Basic EPS
Income available to common shareholders	$	469.4	126.1	$	3.72	$	788.0	138.4	$	5.69	$	357.2	140.0	$	2.55
Income allocated to participating securities	0.3		0.1			0.7		0.1			1.6		0.6
Net income (loss)	$	469.7				$	788.7				$	358.8
Diluted potential common shares			0.8					0.9					1.0
Diluted EPS
Net income (loss)	$	469.7	127.0	$	3.70	$	788.7	139.4	$	5.66	$	358.8	141.6	$	2.53

The balance of outstanding common shares presented in the consolidated statement of shareholders' equity was 121.6 million, 135.6 million and 141.1 million at December 31, 2016, 2015 and 2014, respectively. Included in the outstanding common shares were 1.6 million, 1.9 million and 2.3 million of issued but unvested shares at December 31, 2016, 2015 and 2014, respectively, which are excluded from the basic EPS calculation.

Accumulated Other Comprehensive Loss

Accumulated Other Comprehensive Loss, net of tax, is summarized by component as follows:



	December 31, 2016			December 31, 2015
Pension	$	(98.5	)	$	(121.5	)
Interest rate swaps	—			(0.4		)
SERP/ Retiree medical	20.5			6.1
Foreign currency impact on long term intercompany loan	(19.1		)	(9.2		)
Currency translation adjustment	(89.8		)	(35.5		)
Total accumulated other comprehensive loss	$	(186.9	)	$	(160.5	)

Amortization of the pension plans' net loss reclassified from accumulated other comprehensive loss and realized into costs of sales and selling, general and administrative on the consolidated statements of operations was $5.7, $3.7 and zero for the twelve months ended December 31, 2016, 2015 and 2014, respectively.

Noncontrolling Interest

Noncontrolling interest at December 31, 2016 remained unchanged from the prior year at $0.5.

Repurchases of Common Stock

On July 29, 2015, the Company announced that our Board of Directors authorized a share repurchase program for the purchase of up to $350.0 of our common stock (the "2015 Share Repurchase Program"). During the period ended December 31, 2015, the Company repurchased 5.7 million shares of its class A common stock for $300.0.

On January 27, 2016, the Company announced that our Board of Directors authorized an additional new share repurchase program for the purchase of up to $600.0 of our common stock (the "2016 Share Repurchase Program").

On November 1, 2016, the Company's Board of Directors authorized a share repurchase program for the purchase of up to $600.0 of the Company's common stock (the "2017 Share Repurchase Program").

During the period ended December 31, 2016, the Company repurchased 14.2 million shares of its class A common stock for $649.6, which consisted of the remaining $50.0 from the 2015 Share Repurchase Program and approximately all of the $600.0 of the authorized amount of the 2016 Share Repurchase Program.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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+ Details

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions In December 2014, Onex acquired approximately a 40% interest in Advanced Integration Technologies (“AIT”), a provider of automation and tooling, maintenance services and aircraft components to the aerospace industry and a supplier to the Company. For the twelve months ended December 31, 2016 and 2015, sales from AIT to the Company and its subsidiaries were $13.7 and $18.5, respectively. The amounts owed to AIT and recorded as accrued liabilities were $0.5 and $4.0 as of December 31, 2016 and December 31, 2015, respectively. Tawfiq Popatia, a former director of Spirit Holdings, is a Managing Director of Onex Corporation.

Commitments, Contingencies and Guarantees

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Commitments, Contingencies and Guarantees

Litigation

From time to time the Company is subject to, and is presently involved in, litigation or other legal proceedings arising in the ordinary course of business. While the final outcome of these matters cannot be predicted with certainty, considering, among other things, the meritorious legal defenses available, it is the opinion of the Company that none of these items, when finally resolved, will have a material adverse effect on the Company’s long-term financial position or liquidity. The Company had outstanding obligations in respect of litigation or other legal proceedings of $25.0 for each of the periods ended December 31, 2016 and December 31, 2015, respectively. However, an unexpected adverse resolution of one or more of these items could have a material adverse effect on the results of operations and cash flows in a particular quarter or fiscal year.

From time to time, in the ordinary course of business and similar to others in the industry, we receive requests for information from government agencies in connection with their regulatory or investigational authority. Such requests can include subpoenas or demand letters for documents to assist the government in audits or investigations. We review such requests and notices and take appropriate action. We have been subject to certain requests for information and investigations in the past and could be subject to such requests for information and investigations in the future. Additionally, we are subject to federal and state requirements for protection of the environment, including those for disposal of hazardous waste and remediation of contaminated sites. As a result, we are required to participate in certain government investigations regarding environmental remediation actions.

On December 5, 2014, Boeing filed a complaint in Delaware Superior Court, Complex Commercial Litigation Division, entitled The Boeing Co. v. Spirit AeroSystems, Inc., No. N14C-12-055 (EMD). Boeing seeks indemnification from Spirit for (a) damages assessed against Boeing in International Union, United Automobile, Aerospace and Agricultural Workers of America v. Boeing Co., AAA Case No. 54 300 00795 07 (the “UAW Arbitration”), which was brought on behalf of certain former Boeing employees in Tulsa and McAlester, Oklahoma, and (b) claims that Boeing settled in Society of Professional Engineering Employees in Aerospace v. Boeing Co., Nos. 05-1251-MLB, 07-1043-MLB (D. Kan.) (the “Harkness Class Action”). Spirit Holdings, Spirit and certain Spirit retirement plan entities were parties to the Harkness Class Action, but all claims against the Spirit entities were subsequently dismissed. Boeing’s Complaint asserts that the damages assessed against Boeing in the UAW Arbitration and the claims settled by Boeing in the Harkness Class Action are liabilities that Spirit assumed under an Asset Purchase Agreement between Boeing and Spirit, dated February 22, 2005 (the “APA”). Boeing asserts claims for breach of contract and declaratory judgment regarding its indemnification rights under the APA. Boeing estimates the UAW Arbitration decision to have a net present value of $39.0. In regard to the Harkness Class Action, the district court approved a settlement in an amount of $90.0. In addition to the amounts related to the UAW Arbitration and Harkness Class Action, Boeing seeks indemnification for more than $10.0 in attorneys’ fees it alleges it expended to defend the UAW Arbitration and Harkness Class Action, as well as for the reasonable fees, costs and expenses Boeing expends litigating the case against Spirit. Following a motion to dismiss (which was denied by Court Order dated August 14, 2015), Spirit answered Boeing’s Complaint and asserted a Counterclaim against Boeing, on the ground that the liabilities at issue were Boeing’s responsibility under the APA. Spirit’s Counterclaim alleges breach of contract and seeks a declaratory judgment regarding Spirit’s right to indemnification from Boeing under the APA. Spirit’s Counterclaim seeks to recover the amounts that Spirit spent litigating the Harkness Class Action, responding to Boeing’s indemnification demands concerning the Harkness Class Action and UAW Arbitration, and also litigating the current lawsuit against Boeing. On December 20, 2016, Boeing and Spirit moved for summary judgment. Summary judgment briefing will be completed on February 9, 2017. A decision on the summary judgment motions is not expected until the second quarter of 2017. Trial is presently scheduled for May 2017. Spirit intends to defend vigorously against the allegations in this lawsuit.

On June 3, 2013, a putative class action lawsuit was commenced against the Company, Jeffrey L. Turner, and Philip D. Anderson in the U.S. District Court for the District of Kansas. The court-appointed lead plaintiffs - two pension funds that claim to represent a class of investors in the Company's stock - filed an amended complaint on April 7, 2014, naming as additional defendants Spirit's Vice President of the B787 Program Terry J. George and former Senior Vice President of Oklahoma Operations Alexander K. Kummant. The amended complaint alleges that defendants engaged in a scheme to artificially inflate the market price of the Company's stock by making false statements and omissions about certain programs' performance and costs. It contends that the alleged scheme was revealed by the Company’s accrual of $590.0 in forward loss charges on October 25, 2012. The lead plaintiffs seek certification of a class of all persons other than defendants who purchased Holdings securities between May 5, 2011 and October 24, 2012, and seek an unspecified amount of damages on behalf of the putative class. In June 2014, the defendants filed a motion to dismiss the claims set forth in the amended complaint. On May 14, 2015, the District Court granted Spirit's motion to dismiss and dismissed the matter with prejudice. The plaintiffs filed a notice of appeal on June 11, 2015. On July 5, 2016, the U.S. Court of Appeals for the Tenth Circuit affirmed the District Court’s dismissal. On July 20, 2016, the plaintiffs filed a petition for rehearing and rehearing en banc. On August 2, 2016, the Court of Appeals denied the petition. The plaintiffs did not file a petition for a writ of certiorari by the October 31, 2016 deadline, and this matter is now closed.

Commitments

The Company leases equipment and facilities under various non-cancelable capital and operating leases. The capital leasing arrangements extend through 2026. Minimum future lease payments under these leases at December 31, 2016 are as follows:



			Capital
	Operating		Present Value		Interest		Total
2017	$	10.9	$	0.7	$	0.3	$	11.9
2018	$	7.3	$	0.8	$	0.3	$	8.4
2019	$	5.5	$	0.9	$	0.3	$	6.7
2020	$	4.1	$	0.9	$	0.3	$	5.3
2021	$	3.0	$	0.9	$	0.2	$	4.1
2022 and thereafter	$	12.5	$	4.7	$	7.9	$	25.1

Operating lease payments were as follows:



	2016		2015		2014
Minimum rentals	$	15.4	$	17.8	$	20.5
Total	$	15.4	$	17.8	$	20.5

Spirit's aggregate capital commitments totaled $180.9 and $187.2 at December 31, 2016 and December 31, 2015, respectively.

The Company paid $0.1 and $0.3 in interest expense related to the capital leases for periods ended December 31, 2016 and December 31, 2015, respectively.

Guarantees

Contingent liabilities in the form of letters of guarantee have been provided by the Company. Outstanding guarantees were $20.7 and $20.1 at December 31, 2016 and December 31, 2015, respectively.

Restricted Cash

The Company was required to maintain $19.9 of restricted cash as of both December 31, 2016 and December 31, 2015 related to certain collateral requirements for obligations under its workers’ compensation programs. Restricted cash is included in “Other assets” in the Company's Condensed Consolidated Balance Sheets.

Indemnification

The Company has entered into customary indemnification agreements with each of its Directors, and some of its executive employment agreements include indemnification provisions. Under those agreements, the Company agrees to indemnify each of these individuals against claims arising out of events or occurrences related to that individual’s service as the Company’s agent or the agent of any of its subsidiaries to the fullest extent legally permitted.

Service and Product Warranties and Extraordinary Rework

Provisions for estimated expenses related to service and product warranties and certain extraordinary rework are made at the time products are sold. These costs are accrued at the time of the sale and are recorded to unallocated cost of goods sold. These estimates are established using historical information on the nature, frequency and average cost of warranty claims, including the experience of industry peers. In the case of new development products or new customers, Spirit considers other factors including the experience of other entities in the same business and management judgment, among others. Service warranty and extraordinary work is reported in current liabilities and other liabilities in the Condensed Consolidated Balance Sheet.

The warranty balance presented in the table below includes unresolved warranty claims that are in dispute in regards to their value as well as their contractual liability. The Company estimated the total costs related to some of these claims, however there is significant uncertainty surrounding the disposition of these disputed claims and as such, the ultimate determination of the provision’s adequacy requires significant management judgment. Specific provisions totaling $99.0 and $78.0 were recorded against disputed warranty claims as of December 31, 2016 and December 31, 2015, respectively. These specific provisions represent the Company’s best estimate of reasonably possible warranty costs. Should the Company incur higher than expected warranty costs and/or discover new or additional information related to these warranty provisions, the Company may incur charges that exceed these recorded amounts. The Company utilized available information to make appropriate assessments, however the Company recognizes that data on actual claims experience is of limited duration and therefore, claims projections are subject to judgment. Disputed warranty claims in excess of the specific warranty provision were $209.0 and $192.0, as of December 31, 2016 and December 31, 2015, respectively.

The following is a roll forward of the service warranty and extraordinary rework balance at December 31, 2016, 2015 and 2014:



	2016			2015			2014
Balance, January 1	$	158.7		$	119.9		$	68.7
Charges to costs and expenses	16.7			43.8			53.7
Payouts	(9.5		)	(4.8		)	(1.8		)
Write-offs, net of recoveries	—			—			—
Exchange rate	(2.2		)	(0.2		)	(0.7		)
Balance, December 31	$	163.7		$	158.7		$	119.9

Bonds

Spirit utilized City of Wichita issued Industrial Revenue Bonds ("IRBs") to finance self-constructed and purchased real property at its Wichita site. Tax benefits associated with IRBs include provisions for a ten-year complete property tax abatement and a Kansas Department of Revenue sales tax exemption on all IRB funded purchases. Spirit and its predecessor purchased these IRBs so they are bondholders and debtor / lessee for the property purchased with the IRB proceeds.

Spirit recorded the property net of a capital lease obligation to repay the IRB proceeds on its consolidated balance sheet. Gross assets and liabilities associated with these IRBs were $399.7 and $404.7 as of December 31, 2016 and December 31, 2015, respectively.

Other Income (Expense), Net

12 Months Ended

Dec. 31, 2016

Other Nonoperating Income (Expense) [Abstract]

Other Income (Expense), Net

Other Expense, Net

Other income (expense), net is summarized as follows:



	For the Twelve Months Ended
	December 31, 2016			December 31, 2015			December 31, 2014
KDFA bond	$	3.4		$	3.9		$	3.3
Rental and miscellaneous income (expense)⁽¹⁾	0.3			(2.0		)	0.8
Interest Income	3.6			2.1			0.6
Foreign currency losses	(14.6		)	(6.2		)	(8.2		)
Total	$	(7.3	)	$	(2.2	)	$	(3.5	)


(1)	Includes $2.0 of losses for the period ended December 31, 2015 related to the settlement of interest rate swap agreements as further detailed in Note 11, "Derivative and Hedging Activities."

Foreign currency (losses) gains are due to the impact of movement in foreign currency exchange rates on an intercompany revolver and long-term contractual rights/obligations, as well as trade and intercompany receivables/payables which are denominated in a currency other than the entity’s functional currency.

Significant Concentration of Risk	12 Months Ended
Significant Concentration of Risk	Dec. 31, 2016
Risks and Uncertainties [Abstract]
Significant Concentration Risk	Significant Concentrations of Risk Economic Dependence The Company's largest customer (Boeing) accounted for approximately 81%, 84% and 83% of the revenues for the periods ended December 31, 2016, 2015 and 2014, respectively. Approximately 56% and 48% of the Company's accounts receivable balance at December 31, 2016 and December 31, 2015, respectively, was attributable to Boeing. The Company's second largest customer (Airbus) accounted for approximately 15%, 11% and 10% of the revenues for the periods ended December 31, 2016, 2015 and 2014, respectively. Approximately 28% and 30% of the Company's accounts receivable balance at December 31, 2016 and December 31, 2015, respectively, was attributable to Airbus. Employees As of December 31, 2016, the Company had approximately 12,700 employees located in the Company's four U.S. facilities. Approximately 87% of the Company's U.S. employees are represented by five unions. As of December 31, 2016, the Company had 900 employees located in the Company's two U.K. facilities. Approximately 69%, of the Company's U.K. employees are represented by one union.

Supplemental Balance Sheet Information

12 Months Ended

Dec. 31, 2016

Balance Sheet Related Disclosures [Abstract]

Supplemental Balance Sheet Information

Accrued expenses and other liabilities consist of the following:



	December 31, 2016		December 31, 2015
Accrued expenses
Accrued wages and bonuses	$	32.9	$	32.7
Accrued fringe benefits	117.5		121.1
Accrued interest	5.3		5.6
Workers' compensation	6.7		7.5
Property and sales tax	15.5		25.9
Warranty/extraordinary rework reserve — current	2.9		3.5
Other	35.4		33.9
Total	$	216.2	$	230.2
Other liabilities
Deferred tax liability — non-current	$	0.1	$	13.1
Warranty/extraordinary rework reserve — non-current	160.8		155.2
Customer cost recovery⁽¹⁾	40.7		57.8
Other	74.5		47.4
Total	$	276.1	$	273.5

_____________________________________


(1)	As part of the B787 Amendment, Spirit agreed to pay Boeing for work to complete initial production units; $17.0 in customer cost recovery is reported in other current liabilities on the Condensed Consolidated Balance Sheet

Segment Information

12 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Segment Information

Segment and Geographical Information

The Company operates in three principal segments: Fuselage Systems, Propulsion Systems and Wing Systems. Revenue from Boeing represents a substantial portion of our revenues in all segments. Wing Systems also includes significant revenues from Airbus. Approximately 96% of the Company's net revenues for the twelve months ended December 31, 2016 came from the Company's two largest customers, Boeing and Airbus. All other activities fall within the All Other segment, principally made up of sundry sales of miscellaneous services, tooling contracts and sales of natural gas through a tenancy-in-common with other companies that have operations in Wichita, Kansas. The Company's primary profitability measure to review a segment’s operating performance is segment operating income before corporate selling, general and administrative expenses, research and development and unallocated cost of sales.

Corporate selling, general and administrative expenses include centralized functions such as accounting, treasury and human resources that are not specifically related to the Company's operating segments and are not allocated in measuring the operating segments’ profitability and performance and net profit margins. Research and development includes research and development efforts that benefit the Company as a whole and are not unique to a specific segment. Unallocated cost of sales includes general costs not directly attributable to segment operations, such as warranty, early retirement and other incentives. All of these items are not specifically related to the Company's operating segments and are not utilized in measuring the operating segments’ profitability and performance.

The Company’s Fuselage Systems segment includes development, production and marketing of forward, mid and rear fuselage sections and systems, primarily to aircraft OEMs (OEM refers to aircraft original equipment manufacturer), as well as related spares and maintenance, repairs and overhaul (MRO) services. The Fuselage Systems segment manufactures products at the Company's facilities in Wichita, Kansas and Kinston, North Carolina. The Fuselage Systems segment also includes an assembly plant for the A350 XWB aircraft in Saint-Nazaire, France.

The Company’s Propulsion Systems segment includes development, production and marketing of struts/pylons, nacelles (including thrust reversers) and related engine structural components primarily to aircraft or engine OEMs, as well as related spares and MRO services. The Propulsion Systems segment manufactures products at the Company's facility in Wichita, Kansas.

The Company’s Wing Systems segment includes development, production and marketing of wings and wing components (including flight control surfaces) as well as other miscellaneous structural parts primarily to aircraft OEMs, as well as related spares and MRO services. These activities take place at the Company’s facilities in Tulsa and McAlester, Oklahoma; Kinston, North Carolina; Prestwick, Scotland; and Subang, Malaysia.

The Company’s segments are consistent with the organization and responsibilities of management reporting to the chief operating decision-maker for the purpose of assessing performance. The Company’s definition of segment operating income differs from net profit margin as presented in its primary financial statements and a reconciliation of the segment and consolidated results is provided in the table set forth below.

While some working capital accounts are maintained on a segment basis, much of the Company’s assets are not managed or maintained on a segment basis. Property, plant and equipment, including tooling, is used in the design and production of products for each of the segments and, therefore, is not allocated to any individual segment. In addition, cash, prepaid expenses, other assets and deferred taxes are managed and maintained on a consolidated basis and generally do not pertain to any particular segment. Raw materials and certain component parts are used in the production of aerostructures across all segments. Work-in-process inventory is identifiable by segment, but is managed and evaluated at the program level. As there is no segmentation of the Company’s productive assets, depreciation expense (included in fixed manufacturing costs and selling, general and administrative expenses) and capital expenditures, no allocation of these amounts has been made solely for purposes of segment disclosure requirements.

The following table shows segment revenues and operating income for the twelve months ended December 31, 2016, 2015 and 2014:



	Twelve Months Ended December 31, 2016			Twelve Months Ended December 31, 2015			Twelve Months Ended December 31, 2014
Segment Revenues
Fuselage Systems	$	3,498.8		$	3,447.0		$	3,354.9
Propulsion Systems	1,777.3			1,750.7			1,737.2
Wing Systems	1,508.7			1,437.7			1,695.9
All Other	8.1			8.5			11.2
	$	6,792.9		$	6,643.9		$	6,799.2
Segment Operating Income (Loss) ⁽¹⁾
Fuselage Systems	$	468.6		$	607.3		$	557.3
Propulsion Systems	325.9			378.2			354.9
Wing Systems	223.6			178.5			244.6
All Other	1.6			1.3			3.4
	1,019.7			1,165.3			1,160.2
Corporate SG&A	(228.3		)	(220.8		)	(233.8		)
Unallocated impact of severe weather event (see Note 27)	(12.1		)	—			—
Research and development	(23.8		)	(27.8		)	(29.3		)
Unallocated cost of sales⁽²⁾	(30.4		)	(53.7		)	(72.0		)
Loss on divestiture of programs (see Note 26)	—			—			(471.1		)
Total operating income	$	725.1		$	863.0		$	354.0

_______________________________________


(1)	Inclusive of forward losses, changes in estimate on loss programs and cumulative catch-up adjustments. These changes in estimates for the periods ended December 31, 2016, 2015 and 2014 are further detailed in Note 3 "Changes in Estimates."

(2)

For 2016, includes charges of $13.8 and $23.6, related to warranty reserve and early retirement incentives, respectively, offset by $7.9 for the settlement of historical claims with suppliers. For 2015, includes charges of $40.7, $0.8, and $6.4 related to warranty reserve, reduction in workforce and unallocated inventory write-offs, respectively. In 2014, includes charges of $52.7, $6.0, and $13.0 related to warranty reserve, reduction in workforce and unallocated inventory write-offs, respectively.

Most of the Company's revenue is obtained from sales inside the United States however the Company does generate international sales, primarily from sales to Airbus. The following chart illustrates the split between domestic and foreign revenues:



	Year Ended December 31, 2016				Year Ended December 31, 2015				Year Ended December 31, 2014
Revenue Source⁽¹⁾	Net Revenues		Percent of Total Net Revenues		Net Revenues		Percent of Total Net Revenues		Net Revenues		Percent of Total Net Revenues
United States	$	5,650.1	83	%	$	5,709.0	86	%	$	5,968.3	88	%
International
United Kingdom	690.7		10	%	570.1		9	%	587.5		8	%
Other	452.1		7	%	364.8		5	%	243.4		4	%
Total International	1,142.8		17	%	934.9		14	%	830.9		12	%
Total Revenues	$	6,792.9	100	%	$	6,643.9	100	%	$	6,799.2	100	%

_______________________________________


(1)	Net Revenues are attributable to countries based on destination where goods are delivered.

Most of the Company's long-lived assets are located within the United States. Approximately 4% of the Company's long-lived assets based on book value are located in the United Kingdom as part of Spirit Europe with approximately another 4% of the Company's total long-lived assets located in countries outside the United States and the United Kingdom. The following chart illustrates the split between domestic and foreign assets:



	Year Ended December 31, 2016				Year Ended December 31, 2015				Year Ended December 31, 2014
Asset Location	Total Long-Lived Assets		Percent of Total Long-Lived Assets		Total Long-Lived Assets		Percent of Total Long-Lived Assets		Total Long-Lived Assets		Percent of Total Long-Lived Assets
United States	$	1,828.2	92	%	$	1,755.6	90	%	$	1,598.2	90	%
International
United Kingdom	80.0		4	%	95.0		5	%	124.2		7	%
Other	83.4		4	%	100.1		5	%	61.2		3	%
Total International	163.4		8	%	195.1		10	%	185.4		10	%
Total Long-Lived Assets	$	1,991.6	100	%	$	1,950.7	100	%	$	1,783.6	100	%

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details

Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information

Quarterly Financial Data (Unaudited)



	Quarter Ended
2016	December 31, 2016⁽¹⁾		September 29, 2016⁽²⁾		June 30, 2016⁽³⁾		March 31, 2016⁽⁴⁾
Revenues	$	1,570.0	$	1,711.4	$	1,829.9	$	1,681.6
Gross profit	$	236.8	$	272.0	$	157.9	$	322.6
Operating income	$	160.9	$	214.4	$	83.3	$	266.5
Net income	$	108.2	$	145.1	$	44.8	$	171.6
Earnings per share, basic	$	0.90	$	1.16	$	0.35	$	1.30
Earnings per share, diluted	$	0.89	$	1.16	$	0.35	$	1.29



	Quarter Ended
2015	December 31, 2015⁽⁵⁾		October 1, 2015⁽⁶⁾		July 2, 2015⁽⁷⁾		April 2, 2015⁽⁸⁾
Revenues	$	1,609.4	$	1,593.6	$	1,698.7	$	1,742.2
Gross profit	$	274.3	$	252.6	$	290.8	$	293.9
Operating income	$	205.8	$	191.6	$	230.3	$	235.3
Net income	$	138.3	$	313.6	$	154.9	$	181.9
Earnings per share, basic	$	1.02	$	2.25	$	1.11	$	1.31
Earnings per share, diluted	$	1.01	$	2.24	$	1.11	$	1.30

______________________________________


(1)	Fourth quarter 2016 earnings include the impact of net favorable changes in estimate of $7.5, as well as $11.8 related to early retirement incentives.


(2)	Third quarter 2016 earnings includes the impact of net unfavorable changes in estimate of $5.5.


(3)	Second quarter 2016 earnings include the impact of net unfavorable changes in estimate of $134.7.


(4)	First quarter 2016 earnings includes the impact of net favorable changes in estimate of $47.2, as well as $11.8 related to early retirement incentives.


(5)	Fourth quarter 2015 earnings include the impact of net favorable changes in estimate of $14.2.


(6)	Third quarter 2015 earnings includes the impact of net favorable changes in estimate of $19.0, as well as valuation allowance release of $189.4.


(7)	Second quarter 2015 earnings include the impact of net favorable changes in estimate of $18.8 .


(8)	First quarter 2015 earnings includes the impact of net favorable changes in estimate $14.9, as well as valuation allowance release $42.0.

Condensed Consolidating Financial Information

12 Months Ended

Dec. 31, 2016

Condensed Financial Information of Parent Company Only Disclosure [Abstract]

Condensed Consolidating Financial Information

The 2020 Notes, 2022 Notes, and 2026 Notes were fully and unconditionally guaranteed on a joint and several senior unsecured basis by the Company and its 100% owned domestic subsidiaries, other than Spirit (the “Subsidiary Guarantors”). Following the A&R Credit Agreement, the 2022 Notes and 2026 Notes are fully and unconditionally guaranteed on a joint and several senior unsecured basis by the Company and no subsidiaries are guarantors to any of Spirit's senior notes. As of July 1, 2016, Spirit redeemed the 2020 Notes. For comparative purposes, all statements below have been updated to reflect the effects of the A&R Credit Agreement on the guarantor structure.

The following condensed consolidating financial information, which has been prepared in accordance with the requirements for presentation of Rule 3-10(d) of Regulation S-X promulgated under the Securities Act, presents the condensed consolidating financial information separately for:


(i)	Holdings, as the parent company and parent guarantor to the A&R Credit Agreement, as further detailed in Note 12, Debt;


(ii)	Spirit, as the subsidiary issuer of the 2022 Notes and the 2026 Notes, as well as the 2020 Notes which were outstanding through July 1, 2016;


(iii)	The Company’s subsidiaries, (the “Subsidiary Non-Guarantors”), on a combined basis;


(iv)	Consolidating entries and eliminations representing adjustments to (a) eliminate intercompany transactions between or among Holdings and the Subsidiary Non-Guarantors, (b) eliminate the investments in the Company’s subsidiaries and (c) record consolidating entries; and


(v)	Holdings and its subsidiaries on a consolidated basis.

Condensed Consolidating Statements of Operations and Comprehensive Income

For the Twelve Months Ended December 31, 2016



	Holdings			Spirit			Non-Guarantor Subsidiaries			Consolidating Adjustments			Total
Net Revenues	$	—		$	6,124.6		$	1,284.2		$	(615.9	)	$	6,792.9
Operating costs and expenses
Cost of sales	—			5,255.0			1,164.5			(615.9		)	5,803.6
Selling, general and administrative	8.7			203.6			16.0			—			228.3
Impact of severe weather event	—			12.1			—			—			12.1
Research and development	—			20.8			3.0			—			23.8
Total operating costs and expenses	8.7			5,491.5			1,183.5			(615.9		)	6,067.8
Operating (loss) income	(8.7		)	633.1			100.7			—			725.1
Interest expense and financing fee amortization	—			(57.0		)	(7.8		)	7.5			(57.3		)
Other income (expense), net	—			14.9			(14.7		)	(7.5		)	(7.3		)
(Loss) income before income taxes and equity in net income of affiliates and subsidiaries	(8.7		)	591.0			78.2			—			660.5
Income tax benefit (provision)	2.6			(179.2		)	(15.5		)				(192.1		)
(Loss) income before equity in net income of affiliates and subsidiaries	(6.1		)	411.8			62.7			—			468.4
Equity in net income of affiliates	1.3			—			1.3			(1.3		)	1.3
Equity in net income of subsidiaries	474.5			62.6			—			(537.1		)	—
Net income	469.7			474.4			64.0			(538.4		)	469.7
Other comprehensive loss	(26.4		)	(26.4		)	(61.3		)	87.7			(26.4		)
Comprehensive income	$	443.3		$	448.0		$	2.7		$	(450.7	)	$	443.3

Condensed Consolidating Statements of Operations and Comprehensive Loss

For the Twelve Months Ended December 31, 2015



	Holdings			Spirit			Non-Guarantor Subsidiaries			Consolidating Adjustments			Total
Net Revenues	$	—		$	6,096.1		$	1,030.6		$	(482.8	)	$	6,643.9
Operating costs and expenses
Cost of sales	—			5,095.4			919.7			(482.8		)	5,532.3
Selling, general and administrative	7.1			194.9			18.8			—			220.8
Research and development	—			25.7			2.1			—			27.8
Total operating costs and expenses	7.1			5,316.0			940.6			(482.8		)	5,780.9
Operating (loss) income	(7.1		)	780.1			90.0			—			863.0
Interest expense and financing fee amortization	—			(52.2		)	(7.8		)	7.3			(52.7		)
Other income (expense), net	—			11.3			(6.3		)	(7.2		)	(2.2		)
(Loss) income before income taxes and equity in net income of affiliates and subsidiaries	(7.1		)	739.2			75.9			0.1			808.1
Income tax benefit (provision)	0.1			(8.4		)	(12.3		)				(20.6		)
(Loss) income before equity in net income of affiliates and subsidiaries	(7.0		)	730.8			63.6			0.1			787.5
Equity in net income of affiliates	1.2			—			1.2			(1.2		)	1.2
Equity in net income of subsidiaries	794.5			63.6			—			(858.1		)	—
Net income	788.7			794.4			64.8			(859.2		)	788.7
Other comprehensive loss	(6.7		)	(6.7		)	(21.1		)	27.8			(6.7		)
Comprehensive income	$	782.0		$	787.7		$	43.7		$	(831.4	)	$	782.0

Condensed Consolidating Statements of Operations and Comprehensive Income

For the Twelve Months Ended December 31, 2014



	Holdings			Spirit			Non-Guarantor Subsidiaries			Consolidating Adjustments			Total
Net Revenues	$	—		$	6,242.2		$	1,131.2		$	(574.2	)	$	6,799.2
Operating costs and expenses
Cost of sales	—			5,270.2			1,015.0			(574.2		)	5,711.0
Selling, general and administrative	13.2			200.8			19.8			—			233.8
Research and development	—			27.9			1.4			—			29.3
Loss on sale of Gulfstream programs (see Note 26)	—			471.1			—			—			471.1
Total operating costs and expenses	13.2			5,970.0			1,036.2			(574.2		)	6,445.2
Operating (loss) income	(13.2		)	272.2			95.0			—			354.0
Interest expense and financing fee amortization	—			(87.4		)	(9.8		)	9.1			(88.1		)
Other income (expense), net	—			13.7			(8.1		)	(9.1		)	(3.5		)
(Loss) income before income taxes and equity in net income of affiliates and subsidiaries	(13.2		)	198.5			77.1			—			262.4
Income tax (provision) benefit	(0.8		)	98.0			(1.3		)				95.9
(Loss) income before equity in net income of affiliates and subsidiaries	(14.0		)	296.5			75.8			—			358.3
Equity in net income of affiliates	0.5			—			0.5			(0.5		)	0.5
Equity in net income of subsidiaries	372.3			75.7			—			(448.0		)	—
Net income	358.8			372.2			76.3			(448.5		)	358.8
Other comprehensive loss	(99.2		)	(73.9		)	(25.3		)	99.2			(99.2		)
Comprehensive income	$	259.6		$	298.3		$	51.0		$	(349.3	)	$	259.6

Condensed Consolidating Balance Sheet

December 31, 2016



	Holdings		Spirit		Non-Guarantor Subsidiaries		Consolidating Adjustments			Total
Current assets
Cash and cash equivalents	$	—	$	680.1	$	17.6	$	—		$	697.7
Accounts receivable, net	—		785.0		249.4		(373.9		)	660.5
Inventory, net	—		1,058.8		456.5		—			1,515.3
Other current assets	—		29.0		7.9		—			36.9
Total current assets	—		2,552.9		731.4		(373.9		)	2,910.4
Property, plant and equipment, net	—		1,462.3		529.3		—			1,991.6
Pension assets	—		268.1		14.2		—			282.3
Investment in subsidiary	1,928.8		544.4		—		(2,473.2		)	—
Other assets	—		398.9		101.4		(279.4		)	220.9
Total assets	$	1,928.8	$	5,226.6	$	1,376.3	$	(3,126.5	)	$	5,405.2
Current liabilities
Accounts payable	$	—	$	527.0	$	426.6	$	(373.9	)	$	579.7
Accrued expenses	—		192.8		23.4		—			216.2
Profit sharing	—		97.2		4.2		—			101.4
Current portion of long-term debt	—		25.1		1.6		—			26.7
Advance payments, short-term	—		199.3		—		—			199.3
Deferred revenue, short-term	—		310.8		1.3		—			312.1
Deferred grant income liability — current	—		—		14.4		—			14.4
Other current liabilities	—		94.2		0.2		—			94.4
Total current liabilities	—		1,446.4		471.7		(373.9		)	1,544.2
Long-term debt	—		1,052.5		206.9		(199.4		)	1,060.0
Advance payments, long-term	—		342.0		—		—			342.0
Pension/OPEB obligation	—		43.9		—		—			43.9
Deferred grant income liability — non-current	—		—		63.4		—			63.4
Deferred revenue and other deferred credits	—		143.4		3.4		—			146.8
Other liabilities	—		349.5		6.6		(80.0		)	276.1
Total equity	1,928.8		1,848.9		624.3		(2,473.2		)	1,928.8
Total liabilities and shareholders' equity	$	1,928.8	$	5,226.6	$	1,376.3	$	(3,126.5	)	$	5,405.2

Condensed Consolidating Balance Sheet

December 31, 2015



	Holdings		Spirit		Non-Guarantor Subsidiaries		Consolidating Adjustments			Total
Current assets
Cash and cash equivalents	$	—	$	894.2	$	63.1	$	—		$	957.3
Accounts receivable, net	—		686.3		216.5		(365.8		)	537.0
Inventory, net	—		1,229.0		545.3		0.1			1,774.4
Other current assets	—		24.4		6.0		—			30.4
Total current assets	—		2,833.9		830.9		(365.7		)	3,299.1
Property, plant and equipment, net	—		1,393.1		557.6		—			1,950.7
Pension assets	—		233.3		13.6		—			246.9
Investment in subsidiary	2,120.0		537.8		0.1		(2,657.9		)	—
Other assets	—		504.7		104.0		(340.9		)	267.8
Total assets	$	2,120.0	$	5,502.8	$	1,506.2	$	(3,364.5	)	$	5,764.5
Current liabilities
Accounts payable	$	—	$	538.2	$	445.8	$	(365.8	)	$	618.2
Accrued expenses	—		195.0		35.2		—			230.2
Profit sharing	—		58.3		3.3		—			61.6
Current portion of long-term debt	—		32.2		2.7		—			34.9
Advance payments, short-term	—		178.3		—		—			178.3
Deferred revenue, short-term	—		281.7		3.8		—			285.5
Deferred grant income liability — current	—		—		11.9		—			11.9
Other current liabilities	—		34.7		3.0		—			37.7
Total current liabilities	—		1,318.4		505.7		(365.8		)	1,458.3
Long-term debt	—		1,075.7		270.6		(261.0		)	1,085.3
Advance payments, long-term	—		507.4		—		—			507.4
Pension/OPEB obligation	—		67.7		—		—			67.7
Deferred grant income liability — non-current	—		—		82.3		—			82.3
Deferred revenue and other deferred credits	—		165.6		4.4		—			170.0
Other liabilities	—		328.2		25.3		(80.0		)	273.5
Total equity	2,120.0		2,039.8		617.9		(2,657.7		)	2,120.0
Total liabilities and shareholders' equity	$	2,120.0	$	5,502.8	$	1,506.2	$	(3,364.5	)	$	5,764.5

Condensed Consolidating Statements of Cash Flows

For the Twelve Months Ended December 31, 2016



	Holdings			Spirit			Non-Guarantor Subsidiaries			Consolidating Adjustments		Total
Operating activities
Net cash provided by operating activities	$	—		$	645.9		$	71.0		$	—	$	716.9
Investing activities
Purchase of property, plant and equipment	—			(206.4		)	(47.6		)			(254.0		)
Proceeds from sale of assets	—			0.6			—			—		0.6
Other	—			0.4			(0.4		)	—		—
Net cash used in investing activities	—			(205.4		)	(48.0		)	—		(253.4		)
Financing activities
Proceeds from issuance of bonds	—			299.8			—			—		299.8
Principal payments of debt	—			(33.9		)	(2.5		)	—		(36.4		)
Collection on (repayment of) intercompany debt	—			61.6			(61.6		)	—		—
Payments on term loan	—			(300.0		)	—			—		(300.0		)
Debt issuance and financing costs	—			(17.2		)	—			—		(17.2		)
Taxes paid related to net share settlement awards	—			(15.2		)	—			—		(15.2		)
Excess tax benefits from share-based payment arrangements	—			(0.1		)	—			—		(0.1		)
Proceeds (payments) from subsidiary for purchase of treasury stock	649.6			(649.6		)	—			—		—
Purchase of treasury stock	(649.6		)	—			—			—		(649.6		)
Net cash used in financing activities	—			(654.6		)	(64.1		)	—		(718.7		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(4.4		)	—		(4.4		)
Net decrease in cash and cash equivalents for the period	—			(214.1		)	(45.5		)	—		(259.6		)
Cash and cash equivalents, beginning of period	—			894.2			63.1			—		957.3
Cash and cash equivalents, end of period	$	—		$	680.1		$	17.6		$	—	$	697.7

Condensed Consolidating Statements of Cash Flows

For the Twelve Months Ended December 31, 2015



	Holdings			Spirit			Non-Guarantor Subsidiaries			Consolidating Adjustments		Total
Operating activities
Net cash provided by operating activities	$	—		$	1,167.5		$	122.2		$	—	$	1,289.7
Investing activities
Purchase of property, plant and equipment	—			(273.3		)	(86.8		)			(360.1		)
Proceeds from sale of assets	—			2.7			—			—		2.7
Change in restricted cash	—			—			—			—		—
Other	—			(0.2		)	0.2			—		—
Net cash used in investing activities	—			(270.8		)	(86.6		)	—		(357.4		)
Financing activities
Proceeds from issuance of bonds	—			535.0			—			—		535.0
Principal payments of debt	—			(33.4		)	(3.1		)	—		(36.5		)
Collection on (repayment of) intercompany debt	—			(8.9		)	8.9			—		—
Payments on term loan	—			(534.9		)	—			—		(534.9		)
Debt issuance and financing costs	—			(4.7		)	—			—		(4.7		)
Taxes paid related to net share settlement awards	—			(20.7		)	—			—		(20.7		)
Excess tax benefits from share-based payment arrangements	—			10.5			0.2			—		10.7
Proceeds (payments) from subsidiary for purchase of treasury stock	300.0			(300.0		)	—			—		—
Purchase of treasury stock	(300.0		)	—			—			—		(300.0		)
Net cash used in (provided by) financing activities	—			(357.1		)	6.0			—		(351.1		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(1.8		)	—		(1.8		)
Net increase in cash and cash equivalents for the period	—			539.6			39.8			—		579.4
Cash and cash equivalents, beginning of period	—			354.6			23.3			—		377.9
Cash and cash equivalents, end of period	$	—		$	894.2		$	63.1		$	—	$	957.3

Condensed Consolidating Statements of Cash Flows

For the Twelve Months Ended December 31, 2014



	Holdings			Spirit			Non-Guarantor Subsidiaries			Consolidating Adjustments		Total
Operating activities
Net cash provided by operating activities	$	—		$	312.8		$	48.8		$	—	$	361.6
Investing activities
Purchase of property, plant and equipment	—			(147.4		)	(72.8		)			(220.2		)
Proceeds from sale of assets	—			0.5			—			—		0.5
Change in restricted cash	—			(19.9		)	—			—		(19.9		)
Other	—			2.3			(2.3		)	—		—
Net cash used in investing activities	—			(164.5		)	(75.1		)	—		(239.6		)
Financing activities
Proceeds from issuance of bonds	—			300.0			—			—		300.0
Principal payments of debt	—			(12.9		)	(3.9		)	—		(16.8		)
Collection on (repayment of) intercompany debt	—			7.5			(7.5		)	—		—
Payments on bonds	—			(300.0		)	—			—		(300.0		)
Debt issuance and financing costs	—			(20.8		)	—			—		(20.8		)
Excess tax benefits from share-based payment arrangements	—			2.5			0.1			—		2.6
Proceeds (payments) from subsidiary for purchase of treasury stock	129.2			(129.2		)	—			—		—
Purchase of treasury stock	(129.2		)	—			—			—		(129.2		)
Net cash used in financing activities	—			(152.9		)	(11.3		)	—		(164.2		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(0.6		)	—		(0.6		)
Net decrease in cash and cash equivalents for the period	—			(4.6		)	(38.2		)	—		(42.8		)
Cash and cash equivalents, beginning of period	—			359.2			61.5			—		420.7
Cash and cash equivalents, end of period	$	—		$	354.6		$	23.3		$	—	$	377.9

- Definition

The entire disclosure for condensed financial information, including the financial position, cash flows, and the results of operations of the registrant (parent company) as of the same dates or for the same periods for which audited consolidated financial statements are being presented. Alternatively, the details of this disclosure can be reported by the specific parent company taxonomy elements, indicating the appropriate date and period contexts in an instance document.

+ References + Details

Loss on Divestiture of Programs (Notes)	12 Months Ended
Loss on Divestiture of Programs (Notes)	Dec. 31, 2016
Disposal Groups [Abstract]
Loss on divestiture of programs [Text Block]	26. Loss on Divestiture of Programs On December 9, 2014, the Company entered into an agreement to transfer the Gulfstream programs at the Company’s Tulsa, Oklahoma site to Triumph. The transaction closed on December 30, 2014. Pursuant to the agreement, the Company paid Triumph $160.0 in cash at closing. In accordance with FASB ASU 2014-08, the divestiture of Gulfstream programs were considered an individually significant component that did not qualify for discontinued operations reporting and therefore the loss on the divestiture of Gulfstream programs and the results of its operations are included in continuing operations and disclosure requirements related to pretax profit or loss are described below. The pre-tax loss from the divestiture totaled ($471.1), resulting in a tax benefit of $273.9, including a valuation allowance release related to the divestiture of $118.1, and after tax loss of ($197.2) for the period ended December 31, 2014.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Line Items]

Use of Estimates, Policy [Policy Text Block]

Use of Estimates

The preparation of the Company's financial statements in conformity with GAAP requires management to use estimates and assumptions. The results of these estimates form the basis for making judgments which may affect the reported amounts of assets and liabilities, including the impacts of contingent assets and liabilities, and the reported amounts of revenue and expenses during the reporting period.

Provisions for estimated expenses related to service and product warranties and certain extraordinary rework are made at the time products are sold. These costs are accrued at the time of the sale and are recorded to unallocated cost of goods sold. These estimates are established using historical information on the nature, frequency and average cost of warranty claims, including the experience of industry peers. In the case of new development products or new customers, Spirit considers other factors including the experience of other entities in the same business and management judgment, among others.

Actual results could differ from those estimates and assumptions.

Basis of Presentation and Significant Accounting Policies [Text Block]

Basis of Presentation

The accompanying consolidated financial statements include the Company’s financial statements and the financial statements of its majority owned or controlled subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and Regulation S-X. Investments in business entities in which the Company does not have control, but has the ability to exercise influence over operating and financial policies, including TSACCL, are accounted for under the equity method. KIESC is fully consolidated as the Company owns 77.8% of the entity's equity. All intercompany balances and transactions have been eliminated in consolidation. The Company's U.K. subsidiary uses local currency, the British pound, as its functional currency; the Malaysian subsidiary uses the British pound and the Singapore subsidiary uses the Singapore dollar. All other foreign subsidiaries and branches use the U.S. dollar as their functional currency.

As part of the monthly consolidation process, the functional currencies of the Company's international subsidiaries are translated to U.S. dollars using the end-of-month translation rate for balance sheet accounts and average period currency translation rates for revenue and income accounts.

Research and Development

Research and development includes costs incurred for experimentation, design and testing that are expensed as incurred.

Cash and Cash Equivalents

Cash and cash equivalents represent all highly liquid investments with original maturities of three months or less.

Accounts Receivable

Accounts receivable are recorded at the invoiced amount and do not bear interest. Consistent with industry practice, the Company classifies unbilled receivables related to contracts accounted for under the long-term contract method of accounting, as current. The Company determines an allowance for doubtful accounts based on a review of outstanding receivables. Account balances are charged off against the allowance after the potential for recovery is considered remote. The Company's allowance for doubtful accounts was approximately $5.2 and $6.1 at December 31, 2016 and December 31, 2015, respectively.

Accounts receivable, net includes unbilled receivables on long-term aerospace contracts, comprised principally of revenue recognized on contracts for which amounts were earned but not contractually billable as of the balance sheet date, or amounts earned in which the recovery will occur over the term of the contract, which could exceed one year.

Inventory

Raw materials are stated at lower of cost (principally on an actual or average cost basis) or market. Inventoried costs attributed to units delivered under long-term contracts are based on the estimated average cost of all units expected to be produced and are determined under the learning curve concept which anticipates a predictable decrease in unit costs. Lower unit costs are achieved as tasks and production techniques become more efficient through repetition, supply chain costs are reduced as contracts are negotiated and design changes result in lower cost. This cost averaging usually results in an increase in inventory (referred to as "excess-over-average" or "deferred production costs") during the early years of a contract. These costs are deferred only to the extent the amount of actual or expected excess-over-average is reasonably expected to be fully offset by lower-than-average costs in future periods of a contract. If in-process inventory plus estimated costs to complete a specific contract exceed the actual plus anticipated remaining sales value of such contract, such excess is charged to cost of sales in the period the loss becomes known, thus reducing inventory to estimated realizable value. Costs in inventory include amounts relating to contracts with long production cycles, some of which are not expected to be realized within one year.

The Company reviews its general stock materials and spare parts inventory each quarter to identify impaired inventory, including excess or obsolete inventory, based on historical sales trends and expected production usage. Impaired inventories are written off to work-in-process in the period identified.

Property, Plant and Equipment

Property, plant and equipment are stated at cost less accumulated depreciation. Depreciation is applied using a straight-line method over the useful lives of the respective assets as described in the following table:



	Estimated Useful Life
Land improvements	20 years
Buildings	45 years
Machinery and equipment	3-20 years
Tooling — Airplane program — B787, Rolls-Royce	5-20 years
Tooling — Airplane program — all others	2-10 years
Capitalized software	3-7 years

The Company capitalizes certain costs, such as software coding, installation and testing, that are incurred to purchase or to create and implement internal-use computer software. The Company's capitalization policy includes specifications that the software must have a service life greater than one year, is legally and substantially owned by Spirit, and has an acquisition cost of greater than $0.1.

Where the Company is involved in build-to-suit leasing arrangements, the Company is deemed the owner of the asset for accounting purposes during the construction period of the asset. The Company records the related assets and liabilities for construction costs incurred under these build-to-suit leasing arrangements during the construction period. Upon completion of the asset, the Company considers whether the assets and liabilities qualify for derecognition under the sale-leaseback accounting guidance.

Impairment or Disposal of Long-Lived Assets, and Goodwill

Impairment or Disposal of Long-Lived Assets and Goodwill

Spirit reviews capital and amortizing intangible assets (long-lived assets) for impairment on an annual basis or whenever events or changes in circumstances indicate that the recorded amount may not be recoverable. Under the standard, assets must be classified as either held-for-use or available-for-sale. An impairment loss is recognized when the recorded amount of an asset that is held for use exceeds the projected undiscounted future net cash flows expected from its use and disposal, and is measured as the amount by which the recorded amount of the asset exceeds its fair value, which is measured by discounted cash flows when quoted market prices are not available. For assets available-for-sale, an impairment loss is recognized when the recorded amount exceeds the fair value less cost to sell. The Company performs an annual impairment test for goodwill in the fourth quarter of each year, or more frequently, if an event occurs or circumstances change that would more likely than not reduce fair value below current value.

Deferred Financing Costs

Costs relating to long-term debt are deferred and included in other long-term assets. These costs are amortized over the term of the related debt or debt facilities and are included as a component of interest expense.

Derivative Instruments and Hedging Activities

Derivative Instruments and Hedging Activity

The Company uses derivative financial instruments to manage the economic impact of fluctuations in currency exchange rates and interest rates. Derivative financial instruments are recognized on the consolidated balance sheets as either assets or liabilities and are measured at fair value. Changes in fair value of derivatives are recorded each period in earnings or accumulated other comprehensive income, depending on whether a derivative is effective as part of a hedge transaction, and if it is, the type of hedge transaction. Gains and losses on derivative instruments reported in other comprehensive income are subsequently included in earnings in the periods in which earnings are affected by the hedged item or when the hedge is no longer effective. Cash flows associated with the Company's derivatives are presented as a component of the operating section of the statement of cash flows. The use of derivatives has generally been limited to interest rate swaps and foreign currency forward contracts. The Company enters into foreign currency forward contracts to reduce the risks associated with the changes in foreign exchange rates on sales and cost of sales denominated in currencies other than the entities' functional currency.

Fair Value of Financial Instruments

Financial instruments are measured in accordance with FASB authoritative guidance related to fair value measurements. This guidance clarifies the definition of fair value, prescribes methods for measuring fair value, establishes a fair value hierarchy based on the inputs used to measure fair value, and expands disclosures about fair value measurements. See Note 10, "Fair Value Measurements."

Income Taxes

Income taxes are accounted for in accordance with FASB authoritative guidance on accounting for income taxes. Deferred income tax assets and liabilities are recognized for the future income tax consequences attributable to differences between the financial statement carrying amounts for existing assets and liabilities and their respective tax bases. Tax rate changes impacting these assets and liabilities are recognized in the period during which the rate change occurs.

A valuation allowance, if needed, reduces deferred tax assets to the amount expected to be realized. When determining the amount of net deferred tax assets that are more likely than not to be realized, we assess all available positive and negative evidence. The weight given to the positive and negative evidence is commensurate with the extent the evidence may be objectively verified.

We record an income tax expense or benefit based on the net income earned or net loss incurred in each tax jurisdiction and the tax rate applicable to that income or loss. In the ordinary course of business, there are transactions for which the ultimate tax outcome is uncertain. These uncertainties are accounted for in accordance with FASB authoritative guidance on accounting for the uncertainty in income taxes. The final tax outcome for these matters may be different than management's original estimates made in determining the income tax provision. A change to these estimates could impact the effective tax rate and net income or loss in subsequent periods. We use the flow-through accounting method for tax credits. Under this method, tax credits reduce income tax expense.

Stock-Based Compensation and Other Share-based Payments