Spirit AeroSystems (SPR) 10-Q 6 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended	12 Months Ended
	Apr. 02, 2020	Dec. 31, 2020	Apr. 29, 2020
Cover [Abstract]
Security Exchange Name	NYSE
Title of 12(b) Security	Class A common stock, par value $0.01 per share
Entity Address, Postal Zip Code	67210
City Area Code	316
Local Phone Number	526-9000
Entity Address, State or Province	KS
Entity Address, City or Town	Wichita
Entity Address, Address Line One	3801 South Oliver
Entity Tax Identification Number	20-2436320
Entity Incorporation, State or Country Code	DE
Entity File Number	001-33160
Document Transition Report	false
Document Quarterly Report	true
Entity Registrant Name	Spirit AeroSystems Holdings, Inc.
Entity Central Index Key	0001364885
Document Type	10-Q
Document Period End Date	Apr. 2, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current		Yes
Entity Filer Category	Large Accelerated Filer
Amendment Flag	false
Trading Symbol	SPR
Entity Shell Company	false
Entity Common Stock, Shares Outstanding			105,543,601

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Income Statement [Abstract]
Revenues	$ 1,077.3	$ 1,967.8
Operating costs and expenses
Cost of sales	1,112.5	1,658.3
Selling, general and administrative	77.4	63.6
Restructuring Charges	42.6	0
Research and development	12.3	12.9
Total operating costs and expenses	1,244.8	1,734.8
Operating (loss) income	(167.5)	233
Interest expense and financing fee amortization	(32.2)	(18.8)
Other expense, net	49	11
(Loss) income before income taxes and equity in net (loss) income of affiliate	(248.7)	203.2
Income tax benefit (provision)	87.2	(40.1)
(Loss) income before equity in net (loss) income of affiliate	(161.5)	163.1
Equity in net loss of affiliate	(1.5)	0
Net (loss) income	$ (163)	$ 163.1
(Loss) earnings per share
Earnings Per Share, Basic	$ (1.57)	$ 1.57
Diluted (in dollars per share)	$ (1.57)	$ 1.55

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (163)	$ 163.1
Foreign currency translation adjustments	(35.8)	9.4
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(93.2)	(0.3)
Unrealized foreign exchange (loss) gain on intercompany loan, net of tax effect of $0.9 and ($0.2) for the three months ended, respectively	(2.9)	0.9
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	(9.8)
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	(12.9)	0
Total other comprehensive (loss) gain	(141.7)	10
Total comprehensive (loss) income	$ (304.7)	$ 173.1

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Statement of Comprehensive Income [Abstract]
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	$ 28.8	$ 0.1
Unrealized exchange (loss) on intercompany loan, tax	0.9	(0.2)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	$ 3	$ 0

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Apr. 02, 2020	Dec. 31, 2019	Mar. 28, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 1,833.6	$ 2,350.5	$ 1,228.4	$ 773.6
Restricted Cash, Current	0.3	0.3	$ 0.3	$ 0.3
Accounts receivable, net	508.6	546.4
Unbilled Receivables, Current	380.9	528.3
Inventory, net	1,168.7	1,118.8
Other current assets	134	98.7
Total current assets	4,026.1	4,643
Property, plant and equipment, net	2,253.2	2,271.7
Operating Lease, Right-of-Use Asset	47.5	48.9
Unbilled Receivable, Non Current	10.4	6.4
Pension assets	282.6	449.1
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	192.6	106.5
Goodwill	78.5	2.4
Intangible Assets, Net (Excluding Goodwill)	30.6	1.2
Deferred income taxes	79.6	76.8
Other assets	7,001.1	7,606
Total assets
Liabilities	740.7	1,058.3
Accounts payable	286.1	240.2
Accrued expenses	17.6	84.5
Profit sharing	52.7	50.2
Operating Lease, Liability, Current	5.9	6
Operating lease liabilities, short-term	17.8	21.6
Billings in Excess of Cost, Current	166.9	158.3
Provision for Loss on Contracts	91.5	83.9
Forward loss provision, short-term	17.9	14.8
Deferred grant income liability — current	37	42.9
Other current liabilities	1,434.1	1,760.7
Liabilities Noncurrent
Long-term debt	2,978.2	2,984.1
Operating Lease, Liability, Noncurrent	41.7	43
Advance payments, long-term	327.3	333.3
Pension/OPEB obligation	50.9	35.7
Billings in Excess of Cost, Noncurrent	388.9	356.3
Provision for Loss on Contacts, Non Current	146.9	163.5
Deferred grant income liability — non-current	27.4	29
Deferred revenue and other deferred credits	36.8	34.4
Deferred income taxes	104.3	95.8
Deferred Tax Liabilities, Net, Noncurrent	8.2	8.3
Additional Paid in Capital [Abstract]
Additional paid-in capital	1,125.6	1,125
AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract
Accumulated other comprehensive loss	(250.9)	(109.2)
Retained Earnings Accumulated Deficit [Abstract]
Retained earnings	3,036.9	3,201.3
Treasury Stock, Value	(2,456.8)	(2,456.8)
Total stockholders' equity	1,455.9	1,761.4
Noncontrolling interest	0.5	0.5
Total equity	1,456.4	1,761.9
Total liabilities and equity	7,001.1	7,606
Class A [Member]
Stockholders' Equity Attributable to Parent [Abstract]
Common stock	$ 1.1	$ 1.1

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Apr. 02, 2020	Dec. 31, 2019
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	41,523,470	41,523,470
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	105,399,855	104,882,379
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	0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Operating activities
Net (loss) income	$ (163)	$ 163.1
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities
Depreciation expense	66.8	60.5
Amortization expense	0.5	0
Amortization of deferred financing fees	1.9	0.8
Accretion of customer supply agreement	1.1	1.1
Employee stock compensation expense	9.8	7.7
Loss on Derivative Instruments, Pretax	0	9.6
Gain from foreign currency transactions	(6.5)	(0.1)
Gain (Loss) on Disposition of Property Plant Equipment	0.2	(0.1)
Deferred taxes	(61.5)	8.1
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits	59.9	(6.4)
Grant liability amortization	(2.4)	(5.7)
Equity in net income of affiliate	1.5	0
Increase (Decrease) in Forward Provision	(9)	(11.3)
Changes in assets and liabilities
Accounts receivable, net	36.1	(68.8)
Inventory, net	(59.4)	23.5
Increase (Decrease) in Unbilled Receivables	144.5	(57.6)
Accounts payable and accrued liabilities	(278.6)	129.9
Profit sharing/deferred compensation	(66.7)	(48)
Advance payments	(19.8)	(2.2)
Income taxes receivable/payable	(32.8)	29.4
Increase (Decrease) in Billing in Excess of Cost of Earnings	39.1	4.9
Deferred revenue and other deferred credits	6.3	11.6
Other	2.2	(7.8)
Net cash (used in) provided by operating activities	(331.3)	242.2
Investing activities
Purchase of property, plant and equipment	(31)	(40.8)
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	1.5	0
Payments to Acquire Businesses, Net of Cash Acquired	(118.1)	0
Payments for (Proceeds from) Other Investing Activities	0.3	0.1
Net cash used in investing activities	(147.3)	(40.7)
Financing activities
Proceeds from Lines of Credit	0	100
Proceeds from Issuance of Debt	0
Proceeds from Issuance of Senior Long-term Debt		250
Principal payments of debt	(7.3)	(2.6)
Repayments of Debt	(5.7)	0
Early Repayment of Senior Debt		(2.6)
Payment, Tax Withholding, Share-based Payment Arrangement	(13.1)	(10)
Proceeds from Stock Plans	1.3	0
Debt issuance and financing costs	4.8	0
Payments for Repurchase of Common Stock	0	(75)
Payments of Dividends	(12.4)	(12.7)
Proceeds from (Payments for) Other Financing Activities	10	0
Net cash (used in) provided by financing activities	(32)	249.7
Effect of exchange rate changes on cash and cash equivalents	(6.2)	(0.3)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(516.8)	450.9
Cash, cash equivalents, and restricted cash, beginning of period	2,367.2	794.1
Cash, cash equivalents, and restricted cash, end of period	1,833.6	1,228.4
Reconciliation of Cash, Cash Equivalents, and Restricted Cash [Abstract]
Restricted Cash, Current	0.3	0.3
Restricted Cash, Noncurrent	$ 16.5	$ 16.3

Condensed Statement of Changes

Condensed Statement of Changes in Stockholders' Equity Statement - USD ($) $ in Millions	Total	Class A [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock, Common [Member]	AOCI Including Portion Attributable to Noncontrolling Interest [Member]	Stockholders' Equity, Total [Member]
Stockholders' Equity Attributable to Parent at Dec. 31, 2018								$ 1,237.6
Common Stock, Shares, Outstanding at Dec. 31, 2018			105,461,817
Common Stock, Value, Outstanding at Dec. 31, 2018			$ 1.1
Additional Paid in Capital, Common Stock at Dec. 31, 2018				$ 1,100.9
Treasury Stock, Value at Dec. 31, 2018						$ (2,381)
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2018							$ (196.6)
Retained Earnings (Accumulated Deficit) at Dec. 31, 2018					$ 2,713.2
Net Income (Loss) Attributable to Parent					(163)			(163)
Dividends, Common Stock, Cash					(1.4)			(1.4)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			736,078
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture			$ 0
Stock Issued During Period, Value, Restricted Stock Award, Gross				12.3				12.3
Shares Issued, Shares, Share-based Payment Arrangement, Forfeited			(83,998)
Shares Granted, Value, Share-based Payment Arrangement, Forfeited			$ 0
Payment, Tax Withholding, Share-based Payment Arrangement				(13)				(13)
Stock Issued During Period, Shares, Employee Stock Purchase Plans			55,977
Stock Issued During Period, Value, Employee Stock Purchase Plan				1.3				1.3
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			(190,581)
Other Comprehensive Income (Loss), Net of Tax							(141.7)	(141.7)
Stockholders' Equity Attributable to Parent at Jun. 27, 2019								1,455.9
Common Stock, Shares, Outstanding at Jun. 27, 2019			105,399,855
Additional Paid in Capital, Common Stock at Jun. 27, 2019				1,125.6
Treasury Stock, Value at Jun. 27, 2019						(2,456.8)
Accumulated Other Comprehensive Income (Loss), Net of Tax at Jun. 27, 2019							(250.9)
Retained Earnings (Accumulated Deficit) at Jun. 27, 2019					3,036.9
Common Stock, Value, Outstanding at Jun. 27, 2019			$ 1.1
Stockholders' Equity Attributable to Parent at Dec. 31, 2019	$ 1,761.4							$ 1,761.4
Common Stock, Shares, Outstanding at Dec. 31, 2019			104,882,379
Common Stock, Value, Outstanding at Dec. 31, 2019		$ 1.1	$ 1.1
Additional Paid in Capital, Common Stock at Dec. 31, 2019	1,125			$ 1,125
Treasury Stock, Value at Dec. 31, 2019	2,456.8					$ (2,456.8)
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2019	(109.2)						$ (109.2)
Retained Earnings (Accumulated Deficit) at Dec. 31, 2019	$ 3,201.3				$ 3,201.3
Common Stock, Dividends, Per Share, Declared	$ 0.01
Net Income (Loss) Attributable to Parent	$ (163)
Payment, Tax Withholding, Share-based Payment Arrangement	13.1
Other Comprehensive Income (Loss), Net of Tax	(141.7)
Stockholders' Equity Attributable to Parent at Apr. 02, 2020	1,455.9
Additional Paid in Capital, Common Stock at Apr. 02, 2020	1,125.6
Treasury Stock, Value at Apr. 02, 2020	2,456.8
Accumulated Other Comprehensive Income (Loss), Net of Tax at Apr. 02, 2020	(250.9)
Retained Earnings (Accumulated Deficit) at Apr. 02, 2020	$ 3,036.9

Organization and Basis of Inter

Organization and Basis of Interim Presentation	3 Months Ended
	Apr. 02, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Interim Presentation	Organization and Basis of Interim Presentation Spirit AeroSystems Holdings, Inc. (“Holdings” or the “Company”) provides manufacturing and design expertise in a wide range of fuselage, propulsion, and wing products and services for aircraft original equipment manufacturers (“OEM”) and operators through its subsidiary, Spirit AeroSystems, Inc. (“Spirit”). The Company's headquarters are in Wichita, Kansas, with manufacturing and assembly facilities in Tulsa and McAlester, Oklahoma; Prestwick, Scotland; Wichita, Kansas; Kinston, North Carolina; Subang, Malaysia; Saint-Nazaire, France; San Antonio, Texas; and Biddeford, Maine. The accompanying unaudited interim condensed 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 the instructions to Form 10-Q and Article 10 of Regulation S-X. The Company’s fiscal quarters are 13 weeks in length. Since the Company’s fiscal year ends on December 31, the number of days in the Company’s first and fourth quarters varies slightly from year to year. All intercompany balances and transactions have been eliminated in consolidation. As part of the monthly consolidation process, the Company’s international entities that have functional currencies other than the U.S. dollar 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. The U.K. and Malaysian subsidiaries use the British pound as their functional currency. All other foreign subsidiaries and branches use the U.S. dollar as their functional currency. In the opinion of management, the accompanying unaudited interim condensed consolidated financial statements contain all adjustments (consisting of normal recurring adjustments and elimination of intercompany balances and transactions) considered necessary to fairly present the results of operations for the interim period. The results of operations for the three months ended April 2, 2020 , are not necessarily indicative of the results that may be expected for the year ending December 31, 2020 . In connection with the preparation of the condensed consolidated financial statements, the Company evaluated subsequent events through the date the financial statements were issued. The interim financial statements should be read in conjunction with the audited consolidated financial statements, including the notes thereto, included in the Company’s 2019 Annual Report on Form 10-K filed with the Securities and Exchange Commission (the “SEC”) on February 28, 2020 (the “2019 Form 10-K”). The Company's significant accounting policies are described in Note 3, Summary of Significant Accounting Policies to our consolidated financial statements in the 2019 Form 10-K. The single update to the significant accounting policies described in the 2019 Form 10-K is related to the impact of adopting ASU No. 2016-13, Financial Instruments - Credit losses (Topic 326) ( “ASU 2016-13”) and is described in detail in Note 5, Accounts Receivable, net - Allowance for Credit Losses .

Changes in Estimates

Changes in Estimates	3 Months Ended
	Apr. 02, 2020
Changes in Estimates [Abstract]
Change In Estimate [Text Block]	. Changes in Estimates The Company has a periodic forecasting process in which management assesses the progress and performance of the Company’s programs. This process requires management to review each program’s progress by evaluating the program schedule, changes to identified risks and opportunities, changes to estimated revenues and costs for the accounting contracts (and options if applicable), and any outstanding contract matters. Risks and opportunities include but are not limited to management’s judgment about the cost associated with the Company’s ability to achieve the schedule, technical requirements (e.g., a newly-developed product versus a mature product), and any other program requirements. Due to the span of years it may take to completely satisfy the performance obligations for the accounting contracts (and options, if any) and the scope and nature of the work required to be performed on those contracts, the estimation of total revenue and costs is subject to many variables and, accordingly, is subject to change based upon judgment. When adjustments in estimated total consideration or estimated total cost are required, any changes from prior estimates for fully satisfied performance obligations 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 production efficiencies, assumed rate of production, the rate of overhead absorption, changes to scope of work, and contract modifications. The quarterly and year-to-date forward losses relate primarily to negative changes in estimates on the B787 program due to disruption related to the rate reduction and A350 program due to cost performance and price step downs. Actual results could differ from these estimates, which were based upon circumstances that existed as of the date of the consolidated financial statements, April 2, 2020. Subsequent to this date, there have been significant changes to the global economic situation and to public securities markets as a consequence of the novel strain of coronavirus ("COVID-19") pandemic. It is reasonably possible that this could cause changes to estimates as a result of the financial circumstances of the markets in which the Company operates, the price of the Company’s publicly traded equity in comparison to the Company’s carrying value, and the health of the global economy. Changes in estimates are summarized below: For the Three Months Ended Changes in Estimates April 2, 2020 March 28, 2019 (Unfavorable) Favorable Cumulative Catch-up Adjustment by Segment Fuselage $ (4.0 ) $ (1.2 ) Propulsion (1.5 ) (2.8 ) Wing (2.7 ) (0.2 ) Total (Unfavorable) Favorable Cumulative Catch-up Adjustment $ (8.2 ) $ (4.2 ) Changes in Estimates on Loss Programs (Forward Loss) by Segment Fuselage $ (13.2 ) $ 3.7 Propulsion (3.1 ) 0.5 Wing (3.4 ) 0.5 Total Changes in Estimates (Forward Loss) on Loss Programs $ (19.7 ) $ 4.7 Total Change in Estimate $ (27.9 ) $ 0.5 EPS Impact (diluted per share based upon 2020 forecasted effective tax rate) $ (0.17 ) $ —

Accounts Receivable and Allowan

Accounts Receivable and Allowance for Credit Losses Accounts Receivable and Allowance for Credit Loss (Notes)	3 Months Ended
	Apr. 02, 2020
Receivables [Abstract]
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	. Accounts Receivable, net Accounts receivable represent the Company’s unconditional rights to consideration, subject to the payment terms of the contract, for which only the passage of time is required before payment. Unbilled receivables are reflected under contract assets on the balance sheet. Prior periods allowance for credit losses were based on legacy GAAP. Beginning January 1, 2020, management assesses and records an allowance for credit losses using a current expected credit loss ("CECL") model. See Allowance for Credit Losses, below . Accounts receivable, net consists of the following: April 2, December 31, Trade receivables $ 481.4 $ 515.2 Other 28.1 32.6 Less: allowance for doubtful accounts (0.9 ) (1.4 ) Accounts receivable, net $ 508.6 $ 546.4 The Company has two agreements to sell, on a revolving basis, certain trade accounts receivable balances with Boeing and Airbus to third party financial institutions. These programs were primarily entered into as a result of Boeing and Airbus seeking payment term extensions with the Company and continue to allow Spirit to monetize prior to the payment date for the receivables, subject to payment of a discount. No guarantees are delivered under the agreements. Our ability to continue using such agreements is primarily dependent upon the strength of Boeing’s and Airbus’s financial condition. Transfers under this agreement are accounted for as sales of receivables resulting in the receivables being derecognized from the Company's balance sheet. For the three months ended April 2, 2020 , $718.1 of accounts receivable have been sold via these arrangements. The proceeds from these sales of receivables are included in cash from operating activities in the Consolidated Statement of Cash Flows. The recorded net loss on sale of receivables is $3.1 for the three months ended April 2, 2020 and is included in Other income and expense. See Note 21, Other (Expense) Income, Net . Allowance for Credit Losses Beginning January 1, 2020, management assesses and records an allowance for credit losses on financial assets within the scope of ASU 2016-13 using the CECL model. Prior periods allowance for credit losses were based on a review of outstanding receivables that are charged off against the allowance after the potential for recovery is considered remote in accordance with legacy GAAP. The amount necessary to adjust the allowance for credit losses to management’s current estimate, as of the reporting date, on these assets is recorded in net income as credit loss expense. All credit losses reported in accordance with ASU 2016-13 were on trade receivables and/or contract assets arising from the Company’s contracts with customers. In determining the appropriate methodology to use within the CECL model for receivables and contract assets arising from the Company’s contracts with customers, the Company considered the risk characteristics of the applicable assets. Spirit segregated the trade receivables and Contract Assets into “pools” of assets at the major customer level. The Company's assessment was based on similarity of risk characteristics shared by these pool of assets. Management observed that risks for collectability, with regard to the trade receivables and contract assets resulting from contracts with customers include: macro level economic conditions that impact all of Spirit’s customers, macro level market conditions that could impact Spirit’s customers in certain aircraft categories, certain customer specific market conditions, certain customer specific economic conditions, certain customer specific administrative conditions. The Company selected a loss-rate method for the CECL model, based on the relationship between historical write-offs of receivables and the underlying sales by major customer. Utilizing this model, a historical loss-rate is applied against the amortized cost of applicable assets, at the time the asset is established. The loss rate reflects the Company’s current estimate of the risk of loss (even when that risk is remote) over the expected remaining contractual life of the assets. The Company's policy is to deduct write-offs from the allowance for credit losses account in the period in which the financial assets are deemed uncollectible. The changes to the allowance for credit losses and related credit loss expense reported for the current period were solely based on the unadjusted results of the CECL model. During the reported period, there have been no significant changes in the factors that influenced management’s current estimate of expected credit losses, nor changes to the Company’s accounting policies or CECL methodology. The beginning balances, current period activity, and ending balances of the allocation for credit losses on accounts receivable and contract assets were not material.

Contract with customer, asset a

Contract with customer, asset and liability (Notes)	3 Months Ended
	Apr. 02, 2020
Revenue from Contract with Customer [Abstract]
contract with customer, asset and liability [Text Block]	. Contract Assets and Contract Liabilities Contract assets primarily represent revenues recognized for performance obligations that have been satisfied but for which amounts have not been billed. Contract assets, current are those that are expected to be billed to our customer within 12 months. Contract assets, long-term are those that are expected to be billed to our customer over periods greater than 12 months. No impairments to contract assets were recorded for the period ended April 2, 2020 or the period ended March 28, 2019 . See also Note 5, Accounts Receivable, net - Allowance for Credit Losses . Contract liabilities are established for cash received that is in excess of revenues recognized and are contingent upon the satisfaction of performance obligations. Contract liabilities primarily consist of cash received on contracts for which revenue has been deferred since the receipts are in excess of transaction price resulting from the allocation of consideration based on relative standalone selling price to future units (including those under option that the Company believes are likely to be exercised) with prices that are lower than standalone selling price. These contract liabilities will be recognized earlier if the options are not fully exercised, or immediately, if the contract is terminated prior to the options being fully exercised. April 2, 2020 December 31, 2019 Change Contract assets $ 391.3 $ 534.7 $ (143.4 ) Contract liabilities (555.8 ) (514.6 ) (41.2 ) Net contract assets (liabilities) $ (164.5 ) $ 20.1 $ (184.6 ) For the period ended April 2, 2020 , the decrease in contract assets reflects the net impact of less overtime revenue recognition in relation to billed revenues during the period. The increase in contract liabilities reflects the net impact of additional deferred revenues recorded in excess of revenue recognized during the period. The Company recognized $33.1 of revenue that was included in the contract liability balance at the beginning of the period. March 28, 2019 December 31, 2018 Change Contract assets $ 582.2 $ 523.5 $ 58.7 Contract liabilities (532.4 ) (527.7 ) (4.7 ) Net contract assets (liabilities) $ 49.8 $ (4.2 ) $ 54.0 For the period ended March 28, 2019 , the increase in contract assets reflects the net impact of additional revenues recognized in excess of billed revenues during the period. The increase in contract liabilities reflects the net impact of additional deferred revenues recorded in excess of revenue recognized during the period. The Company recognized $19.4 of revenue that was included in the contract liability balance at the beginning of the period.
Contract with Customer, Asset and Liability [Table Text Block]	April 2, 2020 December 31, 2019 Change Contract assets $ 391.3 $ 534.7 $ (143.4 ) Contract liabilities (555.8 ) (514.6 ) (41.2 ) Net contract assets (liabilities) $ (164.5 ) $ 20.1 $ (184.6 )

Revenue (Notes)

Revenue (Notes)	3 Months Ended
	Apr. 02, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	Disaggregation of Revenue The Company disaggregates revenue based on the method of measuring satisfaction of the performance obligation either over time or at a point in time, based upon the location where products and services are transferred to the customer, and based upon major customer. The Company’s principal operating segments and related revenue are noted in Note 22, Segment Information . The following tables show disaggregated revenues for the three months ended April 2, 2020 and March 28, 2019 : For the Three Months Ended Revenue April 2, March 28, Contracts with performance obligations satisfied over time $ 605.9 $ 1,479.7 Contracts with performance obligations satisfied at a point in time 471.4 488.1 Total Revenue $ 1,077.3 $ 1,967.8 The following table disaggregates revenue by major customer: For the Three Months Ended Customer April 2, March 28, Boeing $ 676.1 $ 1,548.4 Airbus 287.2 329.8 Other 114.0 89.6 Total Revenue $ 1,077.3 $ 1,967.8 The following table disaggregates revenue based upon the location where control of products are transferred to the customer: For the Three Months Ended Location April 2, March 28, United States $ 782.5 $ 1,627.9 International United Kingdom 184.1 209.5 Other 110.7 130.4 Total International 294.8 339.9 Total Revenue $ 1,077.3 $ 1,967.8 Remaining Performance Obligations Unsatisfied, or partially unsatisfied, performance obligations that are expected to be recognized in the future are noted in the table below. The Company expects options to be exercised in addition to the amounts presented below: Remaining in 2020 2021 2022 2023 and After Unsatisfied performance obligations $ 2,955.1 $ 4,716.9 $ 4,806.7 $ 2,767.4

Inventory

Inventory	3 Months Ended
	Apr. 02, 2020
Inventory Disclosure [Abstract]
Inventory	Inventory Inventory consists of raw materials used in the production process, work-in-process, which is direct material, direct labor, overhead and purchases, and capitalized preproduction costs. Raw materials are stated at lower of cost (principally on an actual or average cost basis) or net realizable value. Capitalized pre-production costs include certain contract costs, including applicable overhead, incurred before a product is manufactured on a recurring basis. These costs are typically amortized over a period that is consistent with the satisfaction of the underlying performance obligations to which these relate. April 2, December 31, Raw materials $ 321.0 $ 253.1 Work-in-process (1) 803.1 822.8 Finished goods 16.8 14.5 Product inventory 1,140.9 1,090.4 Capitalized pre-production 27.8 28.4 Total inventory, net $ 1,168.7 $ 1,118.8 (1) Work-in-process inventory includes direct labor, direct material, overhead, and purchases on contracts for which revenue is recognized at a point in time as well as sub-assembly parts that have not been issued to production on contracts for which revenue is recognized using the input method. For the periods ended April 2, 2020 and December 31, 2019 , work-in-process inventory includes $158.2 and $157.2 , respectively, of costs incurred in anticipation of specific contracts and no impairments were recorded in the period. Product inventory, summarized in the table above, is shown net of valuation reserves of $42.2 and $39.0 as of April 2, 2020 and December 31, 2019 , respectively. Excess capacity and abnormal costs are excluded from inventory and recognized as expense in the period incurred. Cost of sales for the period ended April 2, 2020 includes the impact of $73.4 in excess capacity costs related to the B737 MAX production schedule adjustment that began on January 1, 2020, and the impact of $25.4

Property, Plant and Equipment

Property, Plant and Equipment	3 Months Ended
	Apr. 02, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, net	Property, Plant and Equipment, net Property, plant and equipment, net consists of the following: April 2, December 31, Land $ 17.2 $ 15.9 Buildings (including improvements) 926.5 924.0 Machinery and equipment 1,989.9 1,941.5 Tooling 1,051.3 1,047.4 Capitalized software 277.3 277.8 Construction-in-progress 178.3 192.8 Total 4,440.5 4,399.4 Less: accumulated depreciation (2,187.3 ) (2,127.7 ) Property, plant and equipment, net $ 2,253.2 $ 2,271.7 Capitalized interest was $1.2 and $2.1 for the three months ended April 2, 2020 and March 28, 2019, respectively. Repair and maintenance costs are expensed as incurred. The Company recognized repair and maintenance costs of $30.5 and $35.6 for the three months ended April 2, 2020 and March 28, 2019 , 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 $4.3 and $4.3 for the three months ended April 2, 2020 and March 28, 2019 , 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. For the period ended April 2, 2020

Leases (Notes)

Leases (Notes)	3 Months Ended
	Apr. 02, 2020
Leases [Abstract]
Leases of Lessee Disclosure [Text Block]	The Company determines if an arrangement is a lease at the inception of a signed agreement. Operating leases are included in in right-of-use (“ROU”) assets (long-term), short-term operating lease liabilities, and long-term operating lease liabilities on the Company’s consolidated balance sheet. Finance leases are included in Property, Plant and Equipment, current maturities of long-term debt, and long-term debt. ROU assets represent the right of the Company to use an underlying asset for the length of the lease term, and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. To determine the present value of lease payments, the Company uses its estimated incremental borrowing rate or the implicit rate, if readily determinable. The estimated incremental borrowing rate is based on information available at the lease commencement date, including any recent debt issuances and publicly available data for instruments with similar characteristics. The ROU asset also includes any lease payments made and excludes lease incentives. The Company's lease terms may include options to extend or terminate the lease and, when it is reasonably certain that an option will be exercised, those options are included in the net present value calculation. Leases with a term of 12 months or less, which are primarily related to automobiles and manufacturing equipment, are not recorded on the balance sheet. The aggregate amount of lease cost for leases with a term of 12 months or less is not material. The Company has lease agreements that include lease and non-lease components, which are generally accounted for separately. For certain leases (primarily related to IT equipment), the Company does account for the lease and non-lease components as a single lease component. A portfolio approach is applied to effectively account for the ROU assets and liabilities for those specific leases referenced above. The Company does not have any material leases containing variable lease payments or residual value guarantees. The Company also does not have any material subleases. The Company currently has operating and finance leases for items such as manufacturing facilities, corporate offices, manufacturing equipment, transportation equipment, and vehicles. The Company's active leases have remaining lease terms that range between less than one year to 18 years, some of which include options to extend the leases for up to 30 years, and some of which include options to terminate the leases within one year. For the three months ended April 2, 2020 , total net lease cost was $9.6 . This was comprised of $2.2 of operating lease costs, $5.8 amortization of assets related to finance leases, and $1.6 interest on finance lease liabilities. For the three months ended March 28, 2019 , total net lease cost was $4.4 . This was comprised of $2.2 of operating lease costs, $1.8 amortization of assets related to finance leases, and $0.4 interest on finance lease liabilities. Supplemental cash flow information related to leases was as follows: For the Three Months Ended For the Three Months Ended April 2, 2020 March 28, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 2.2 $ 2.2 Operating cash flows from finance leases $ 1.6 $ 0.4 Financing cash flows from finance leases $ 6.7 $ 1.8 ROU assets obtained in exchange for lease obligations: Operating leases $ 0.2 $ 0.1 Supplemental balance sheet information related to leases: April 2, 2020 December 31, 2019 Finance leases: Property and equipment, gross $ 194.8 $ 165.5 Accumulated amortization (28.9 ) (23.5 ) Property and equipment, net $ 165.9 $ 142.0 The weighted average remaining lease term as of April 2, 2020 for operating and finance leases was 10.1 years and 6.2 years, respectively. The weighted average discount rate as of April 2, 2020 for operating and finance leases was 5.6% and 4.2% , respectively. The weighted average remaining lease term as of December 31, 2019 for operating and finance leases was 10.2 years and 6.5 years, respectively. The weighted average discount rate as of December 31, 2019 for operating and finance leases was 5.6% and 4.3% , respectively. See Note 15, Debt , for current and non-current finance lease obligations. There has not been a significant impact on lease terms, costs, cash flows, or balance sheet values, including any impairment of lease assets, as a result of the COVID-19 pandemic. As of April 2, 2020 , remaining maturities of lease liabilities were as follows: 2020 2021 2022 2023 2024 2025 and thereafter Total Lease Payments Less: Imputed Interest Total Lease Obligations Operating Leases $ 6.4 $ 7.5 $ 7.1 $ 6.1 $ 5.6 $ 30.3 $ 63.0 $ (15.4 ) $ 47.6 Financing Leases $ 25.3 $ 33.4 $ 29.6 $ 25.5 $ 20.0 $ 37.1 $ 170.9 $ (21.1 ) $ 149.8 As of April 2, 2020 , the Company had additional operating and financing lease commitments that have not yet commenced of approximately $2.8 and $51.9 for manufacturing equipment and facilities which are in various phases of construction or

Other Assets

Other Assets	3 Months Ended
	Apr. 02, 2020
Other Assets, Noncurrent [Abstract]
Other Assets	Other Assets are summarized as follows: April 2, December 31, Deferred financing Deferred financing costs 45.1 41.7 Less: Accumulated amortization - deferred financing costs (37.5 ) (36.9 ) Deferred financing costs, net 7.6 4.8 Other Supply agreements (1) 10.1 11.5 Equity in net assets of affiliates 6.2 7.7 Restricted cash - collateral requirements 16.5 16.4 Other 39.2 36.4 Total $ 79.6 $ 76.8 (1) Certain payments accounted for as consideration paid by the Company to a customer are being amortized as reductions to net revenues.

Advance Payments and Deferred R

Advance Payments and Deferred Revenue/Credits	3 Months Ended
	Apr. 02, 2020
Advance Payments And Deferred Revenue Credits [Abstract]
Advance Payments And Deferred Revenue Credits	Advance Payments Advances on the B787 Program. Boeing has made advance payments to Spirit under the B787 Special Business Provisions and General Terms Agreement (collectively, the “B787 Supply Agreement”) that are required to be repaid to Boeing by way of offset against the purchase price for future shipset deliveries. Advance repayments were initially scheduled to be spread evenly over the remainder of the first 1,000 B787 shipsets delivered to Boeing. On April 8, 2014, the Company signed a memorandum of agreement with Boeing that 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 that otherwise would have become due during such twelve-month period will offset the purchase price for shipsets 1,001 through 1,120. On December 21, 2018, the Company signed the 2018 MOA with Boeing that again suspended the advance repayments beginning with line unit 818. The advance repayments will resume at a lower rate of $0.45 per shipset at line number 1135 and continue through line number 1605. In the event Boeing does not take delivery of a sufficient number of shipsets to repay the full amount of advances prior to the termination of the B787 program or the B787 Supply Agreement, any advances not then repaid will be applied against any outstanding payments then due by Boeing to us, and any remaining balance will be repaid in annual installments of $42.0 due on December 15th of each year until the advance payments have been fully recovered by Boeing. As of April 2, 2020 , the amount of advance payments received by us from Boeing under the B787 Supply Agreement and not yet repaid was approximately $212.1 . Advances on the B737 Program. On April 12, 2019, Boeing and the Company executed a Memorandum of Agreement (the “2019 MOA”) relating to Spirit's production of aircraft with respect to the B737 program. In an effort to minimize the disruption to Spirit's operations and its supply chain, the 2019 MOA included the terms and conditions for an advance payment to be made from Boeing to Spirit in the amount of $123.0 , which was received during the third quarter of 2019. On February 6, 2020, Boeing and Spirit entered into a Memorandum of Agreement (the “2020 MOA”). The 2020 MOA extended the repayment date of the $123 million advance received by Spirit under the 2019 MOA to 2022. The 2020 MOA also required Boeing to pay $225 to Spirit in the first quarter of 2020, consisting of (i) $70 in support of Spirit’s inventory and production stabilization, of which $10 will be repaid by Spirit in 2021, and (ii) $155

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Apr. 02, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The 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 the interest rate swaps and foreign currency hedge contracts. Level 3 Unobservable inputs that are supported by little or no market activity and 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. At April 2, 2020, the Company’s long-term debt includes the 2018 Term Loan and 2018 Revolver (as such terms are defined below), senior secured notes, and senior unsecured notes. 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: April 2, 2020 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value 2018 Term Loan (including current portion) $ 432.4 $ 404.9 (2) $ 438.5 $ 440.1 (2) 2018 Revolver 800.0 800.0 (2) 800.0 800.0 (2) Senior unsecured floating rate notes due 2021 299.3 286.3 (1) 299.1 298.4 (1) Senior unsecured notes due 2023 298.4 254.0 (1) 298.3 307.2 (1) Senior secured notes due 2026 297.9 257.1 (1) 297.8 305.6 (1) Senior unsecured notes due 2028 694.2 576.3 (1) 694.1 734.4 (1) Total $ 2,822.2 $ 2,578.6 $ 2,827.8 $ 2,885.7 (1) Level 1 Fair Value hierarchy (2) Level 2 Fair Value hierarchy

Derivative and Hedging Activiti

Derivative and Hedging Activities	3 Months Ended
	Apr. 02, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative and Hedging Activities	Derivative and Hedging Activities The Company has traditionally entered into interest rate swap agreements to reduce its exposure to the variable rate portion of its long-term debt. 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 2018 Credit Agreement (as defined below) 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 15, Debt , for more information. Derivatives Not Accounted for as Hedges Interest Rate Swaps On March 15, 2017, the Company entered into an interest rate swap agreement, with an effective date of March 31, 2017. The swaps have a notional value of $250.0 and fix the variable portion of the Company’s floating rate debt at 1.815% . The swap expired in March 2020. The fair value of the swap, using Level 2 inputs, was a liability of $0.0 as of April 2, 2020 and $0.1 as of December 31, 2019 . The Company recorded $0.0 swap activity for the three months ended April 2, 2020 . Derivatives Accounted for as Hedges Cash Flow Hedges During the third quarter of 2019, the Company entered into two interest rate swap agreements with a combined notional value of $450.0. These derivatives have been designated as cash flow hedges by the Company. The fair value of these hedges was a liability of $13.7 as of April 2, 2020 . Changes in the fair value of cash flow hedges are recorded in Accumulated Other Comprehensive Income ("AOCI") and recorded in earnings in the period in which the hedged transaction occurs. The loss recognized in AOCI was $12.9 for the three months ended April 2, 2020 . For the three months ended April 2, 2020 , a loss of $0.1 was reclassified from AOCI to earnings. Within the next 12 months, the Company expects to recognize a loss of $5.7 in earnings related to these hedged contracts. As of April 2, 2020, the maximum term of hedged forecasted transactions was 3 years.

Debt

Debt	3 Months Ended
	Apr. 02, 2020
Debt Disclosure [Abstract]
Debt	Debt Total debt shown on the balance sheet is comprised of the following: April 2, 2020 December 31, 2019 Current Noncurrent Current Noncurrent 2018 Term Loan $ 22.7 $ 409.7 $ 22.8 $ 415.7 2018 Revolver — 800.0 — 800.0 Senior unsecured floating rate notes due 2021 — 299.3 — 299.1 Senior unsecured notes due 2023 — 298.4 — 298.3 Senior secured notes due 2026 — 297.9 — 297.8 Senior unsecured notes due 2028 — 694.2 — 694.1 Present value of finance lease obligations 28.2 121.6 25.8 121.3 Other 1.8 57.1 1.6 57.8 Total $ 52.7 $ 2,978.2 $ 50.2 $ 2,984.1 2018 Credit Agreement On July 12, 2018, the Company entered into a $1,256.0 senior unsecured Second Amended and Restated Credit Agreement (the “2018 Credit Agreement”) among Spirit, as borrower, the Company, as parent guarantor, the lenders party thereto, Bank of America, N.A., as administrative agent, (the “Administrative Agent”) and the other agents named therein, consisting of a $800.0 revolving credit facility (the “2018 Revolver”), a $206.0 term loan A facility (the “2018 Term Loan”) and a $250.0 delayed draw term loan facility (the “2018 DDTL”). Each of the 2018 Revolver, the 2018 Term Loan and the 2018 DDTL matures on July 12, 2023, and prior to the February 2020 Amendment (as defined below), bears interest, at Spirit’s option, ranging between LIBOR plus 1.125% and LIBOR plus 1.875% (or between base rate plus 0.125% and base rate plus 0.875%, as applicable) based on Spirit’s senior unsecured ratings provided by Standard & Poor’s Financial Services LLC (“S&P”) and/or Moody’s Investors Service, Inc. (“Moody’s”) The principal obligations under the 2018 Term Loan are to be repaid in equal quarterly installments of $2.6 , commencing with the fiscal quarter ending March 31, 2019, and with the balance due at maturity of the 2018 Term Loan. The principal obligations under the 2018 DDTL are to be repaid in equal quarterly installments of $3.1, subject to adjustments for any extension of the availability period of the 2018 DDTL, commencing with the fiscal quarter ending June 27, 2019, and with the balance due at maturity of the 2018 DDTL. The 2018 Credit Agreement also contains an accordion feature that provides Spirit with the option to increase the 2018 Revolver commitments and/or institute one or more additional term loans by an amount not to exceed $750.0 in the aggregate, subject to the satisfaction of certain conditions and the participation of the lenders. The 2018 Credit Agreement contains customary affirmative and negative covenants, including certain financial covenants that are tested on a quarterly basis. Spirit’s obligations under the 2018 Credit Agreement may be accelerated upon an event of default, which includes non-payment of principal or interest, material breach of a representation or warranty, material breach of a covenant, cross-default to material indebtedness, material judgments, ERISA events, change in control, bankruptcy and invalidity of the guarantee of Spirit’s obligations under the 2018 Credit Agreement made by the Company. Under the 2018 Credit Agreement, the pricing table and tiers are as follows. Pricing Tier Credit Rating (S&P/Moody's) Revolving Commitment Fee Applicable Rate For LIBOR Loans and Letter of Credit Fees Applicable Rate for Base Rate Loans I Greater than or equal to BBB+ / Baa1 0.125% 1.125% 0.125% II BBB / Baa2 0.150% 1.250% 0.250% III BBB- / Baa3 0.200% 1.375% 0.375% IV BB+ / Ba1 0.300% 1.625% 0.625% V BB / Ba2 0.375% 1.875% 0.875% The February 2020 Amendment On February 24, 2020, the Company entered into an amendment (the “February 2020 Amendment”) to the 2018 Credit Agreement among Spirit, as borrower, Holdings, as parent guarantor, the lenders party thereto, the Administrative Agent, and the other agents named therein. On February 24, 2020, Spirit also entered into a $375.0 senior unsecured delayed draw term loan among Spirit, as borrower, Holdings, as parent guarantor, Spirit NC (as defined below), the lenders party thereto, and the Administrative Agent (the “2020 DDTL”). Under the terms of the 2020 DDTL, if Spirit receives net cash proceeds from issuances of indebtedness or equity that exceed the amount of the 2020 DDTL, the commitments under that facility will be canceled and any amounts outstanding prepaid. The primary purpose for entering into the February 2020 Amendment was to obtain covenant relief with respect to expected breaches of the total leverage ratio and interest coverage ratios under the 2018 Credit Agreement. Given the production suspension beginning on January 1, 2020 and lower 2020 production rate for the B737 MAX, absent a waiver or an amendment of the 2018 Credit Agreement, the Company was expected to breach the total leverage ratio beginning with the first fiscal quarter of 2020 and continuing into 2021. The February 2020 Amendment waived or modified the testing of the ratios set forth in the 2018 Credit Agreement until the commencement of the second fiscal quarter of 2021 (the “Reversion Date”) and put the following financial ratios and tests in place for such time period: • Senior Secured Leverage Ratio: Commencing with the first fiscal quarter of 2020, the ratio of senior secured debt to consolidated EBITDA over the last twelve months shall not, as of the end of the applicable fiscal quarter, be greater than: (i) 3.00:1.00, with respect to the first fiscal quarter of 2020; (ii) 4.25:1.00, with respect to the second fiscal quarter of 2020; (iii) 5.50:1.00, with respect to the third fiscal quarter of 2020; (iv) 5.00:1.00, with respect to the fourth fiscal quarter of 2020; and (v) 3.00:1.00, with respect to the first fiscal quarter of 2021. • Interest Coverage Ratio: Commencing with the first fiscal quarter of 2020, the interest coverage ratio as of the end of the applicable fiscal quarter shall not be less than: (i) 4.00:1.00, with respect to the first fiscal quarter of 2020; (ii) 3.75:1.00, with respect to the second fiscal quarter of 2020; (iii) 2.50:1.00, with respect to the third fiscal quarter of 2020; (iv) 2.25:1.00, with respect to the fourth fiscal quarter of 2020; and (v) 3.75:1.00, with respect to the first fiscal quarter of 2021. • Minimum Liquidity: As of the end of each fiscal month, commencing with the first fiscal month after entering into the 2020 Amendment, the Company shall have minimum liquidity of not less than: (i) $1,000 through, and including, the last fiscal month ending in the third fiscal quarter of 2020; (ii) $850, as of the end of each fiscal month ending in the fourth fiscal quarter of 2020; and (iii) $750 , as of the end of each fiscal month ending in the first fiscal quarter of 2021; provided, however, that if the Company receives proceeds of at least $750 from the issuance of indebtedness before the Reversion Date, the minimum liquidity requirement shall remain at $1,000. Liquidity includes cash and cash equivalents and amounts available to be drawn under the 2018 Revolver and the 2020 DDTL. The February 2020 Amendment provided that, upon the Reversion Date, the ratios will revert back to the ratios in the 2018 Credit Agreement except that the total leverage ratio will be 4.00:1.00, with respect to the second fiscal quarter of 2021, returning to 3.50:1:00 thereafter. The Senior Secured Leverage Ratio and minimum liquidity covenants will no longer be applicable following the Reversion Date. The February 2020 Amendment added Spirit AeroSystems North Carolina, Inc. as an additional guarantor (“Spirit NC”) and provides for the grant of security interests to the lenders under the 2018 Credit Agreement with respect to certain real property and personal property, including certain equity interests, owned by Spirit, as borrower, and the Guarantors (as defined below), which include the Company and Spirit NC. Such guarantee and security interests will be released, at the option of Spirit, so long as no default or event of default shall exist at the time thereof, or immediately after giving effect thereto, if (A) (I) the senior unsecured debt rating of Spirit is “BBB-” or higher as determined by S&P, and (II) the senior unsecured debt rating of Spirit is “Baa3” or higher as determined by Moody’s, or (B) S&P and Moody’s have each confirmed, in a writing in form and substance reasonably satisfactory to the administrative agent, that (I) the senior unsecured debt rating of Spirit will be “BBB-” or higher as determined by S&P, and (II) the senior unsecured debt rating of Spirit will be “Baa3” or higher as determined by Moody’s, in each case of the foregoing clauses (B)(I) and (B)(II), after giving effect to the release of the security (the date of such release, the “Security Release Date”). The February 2020 Amendment also added increased restrictions on our ability to incur additional indebtedness, consolidate or merge, make acquisitions and other investments (although the Asco Acquisition and the Bombardier Acquisition (each as defined below) are expressly permitted thereunder), guarantee obligations of third parties, make loans or advances, declare or pay certain dividends or distributions on our stock, redeem or repurchase shares of our stock, or pledge assets. The February 2020 Amendment provides that a number of these increased restrictions will no longer apply following the Security Release Date. The accordion feature to increase the 2018 Revolver commitments and/or institute one or more additional term loans will not be available to Spirit during the period between the effective date of the February 2020 Amendment and the Security Release Date. Spirit’s obligations under the 2018 Credit Agreement may be accelerated upon an event of default, which includes non-payment of principal or interest, material breach of a representation or warranty, breach of a covenant, cross-default to material indebtedness, material judgments, ERISA events, change in control, bankruptcy and invalidity of the guarantee of Spirit’s obligations under the Credit Agreement made by the Company. The February 2020 Amendment added new events of default for validity, perfection and priority of liens and the public announcement by Boeing of the termination or permanent cessation of the B737 MAX program that will no longer apply following the Security Release Date. Under the February 2020 Amendment, the pricing table and tiers were updated to reflect the below. The pricing table was further updated under the April 2020 Amendment (as described below). Pricing Tier Credit Rating (S&P/Moody's) Revolving Commitment Fee Applicable Rate For LIBOR Loans and Letter of Credit Fees Applicable Rate for Base Rate Loans I Greater than or equal to BBB+ / Baa1 0.125% 1.625% 0.625% II BBB / Baa2 0.150% 1.750% 0.750% III BBB- / Baa3 0.200% 1.875% 0.875% IV BB+ / Ba1 0.300% 2.125% 1.125% V BB / Ba2 0.375% 2.375% 1.375% VI Less than or equal to BB- / Ba3 0.500% 2.625% 1.625% April 2020 Amendment The April 2020 Amendment . On April 13, 2020, Spirit, the Company, and Spirit NC entered into a further amendment to the 2018 Credit Agreement (the “April 2020 Amendment”). The April 2020 Amendment became effective upon April 17, 2020, when Spirit issued the 2025 Notes. As a result of the issuance of the 2025 Notes and the effectiveness of the April 2020 Amendment, the commitments under the 2020 DDTL were canceled in full and the facility was terminated. The primary purpose for entering into the April 2020 Amendment was to permit Spirit to issue the 2025 Notes and provide covenant flexibility for future capital raises and to take into account market conditions. The April 2020 Amendment waived or modified the testing of the ratios set forth in the 2018 Credit Agreement, as amended, by the February 2020 Amendment, and put the following financial ratios and tests in place: • First Lien Leverage Ratio: Commencing with the first fiscal quarter of 2020, the ratio of first lien senior secured debt to consolidated EBITDA over the last twelve months shall not, as of the end of the applicable fiscal quarter, be greater than: (i) 3.00:1.00, with respect to the first fiscal quarter of 2020; (ii) 4.50:1.00, with respect to the second fiscal quarter of 2020; (iii) 6.50:1.00, with respect to the third fiscal quarter of 2020; (iv) 6.75:1.00, with respect to the fourth fiscal quarter of 2020; (v) 5.00:1.00, with respect to the first fiscal quarter of 2021; (vi) 4.50:1.00, with respect to the second fiscal quarter of 2021; (vii) 3.50:1.00, with respect to the third fiscal quarter of 2021; and (viii) 3.00:1.00 thereafter through the fourth fiscal quarter of 2022. • Interest Coverage Ratio: Commencing with the first fiscal quarter of 2020, the interest coverage ratio shall not, as of the end of the applicable fiscal quarter, be less than: (i) 4.00:1.00, with respect to the first fiscal quarter of 2020; (ii) 2.25:1.00, with respect to the second fiscal quarter of 2020; (iii) 1.25:1.00, with respect to the third fiscal quarter of 2020; (iv) 1.25:1.00, with respect to the fourth fiscal quarter of 2020; (v) 1.75:1.00, with respect to the first fiscal quarter of 2021; (vi) 2.25:1.00, with respect to the second fiscal quarter of 2021; (vii) 2.50:1.00, with respect to the third fiscal quarter of 2021; (viii) 2.75:1.00, with respect to the fourth fiscal quarter of 2021; (ix) 3.00:1.00, with respect to the first fiscal quarter of 2022; (x) 3.25:1.00, with respect to the second fiscal quarter of 2022; (xi) 3.75:1.00 with respect to the third fiscal quarter of 2022; (xii) 3.75:1.00 with respect to the fourth fiscal quarter of 2022; and (xiii) 4.00:1.00 thereafter. • Total Leverage Ratio: Testing of the total leverage ratio will be suspended until the first fiscal quarter of 2022. Commencing with the first fiscal quarter of 2022, the ratio of indebtedness to consolidated EBIDTA over the last twelve months, shall not, as of the end of the applicable fiscal quarter, be greater than (i) 5.50:1.00, with respect to the first fiscal quarter of 2022; (ii) 5.00:1:00, with respect to the second fiscal quarter of 2022; (iii) 4.75:1.00, with respect to the third fiscal quarter of 2022; (iv) 4.50:1.00, with respect to the fourth fiscal quarter of 2022; and (v) 3.50:1.00 thereafter. • Minimum Liquidity: As of the end of each fiscal month, commencing with the first fiscal month until the end of the fourth fiscal quarter of 2021, the Company shall have minimum liquidity of not less than $1,000. The April 2020 Amendment provides that, following the fourth fiscal quarter of 2022, the ratios will revert back to the ratios in the 2018 Credit Agreement prior to giving effect to any amendments. The minimum liquidity covenant will no longer be applicable following the fourth fiscal quarter of 2021. The first lien leverage ratio will no longer be applicable following the fourth fiscal quarter of 2022. Additionally, the April 2020 Amendment also requires Spirit to demonstrate pro-forma compliance with the financial covenants set forth in the 2018 Credit Agreement for future borrowings under the 2018 Revolver. All 2018 Revolver draws and other credit extensions under the 2018 Credit Agreement are subject to the Company making a representation that no material adverse effect has occurred on the Company’s operations, business, assets, properties, liabilities, or financial condition (among other items) since a specified date. The April 2020 Amendment added a provision that the impacts of the COVID-19 pandemic on the business, operations and/or financial condition of the Company occurring prior to December 31, 2020 that were publicly disclosed or disclosed to the Administrative Agent prior to the effectiveness of the April 2020 Amendment will be disregarded when considering whether a material adverse effect has occurred when this representation is made. Each of the 2018 Revolver, the 2018 Term Loan and the 2018 DDTL continues to mature on July 12, 2023, and, following the effectiveness of the April 2020 Amendment, will bear interest at a rate, at Spirit’s option, ranging between LIBOR plus 3.125% and LIBOR plus 4.125% (or between base rate plus 2.125% and base rate plus 3.125%, as applicable) based on Spirit’s senior unsecured ratings provided by S&P and/or Moody’s as reflected in the pricing table below: Pricing Tier Credit Rating (S&P/Moody's) Revolving Commitment Fee Applicable Rate For LIBOR Loans and Letter of Credit Fees Applicable Rate for Base Rate Loans I Greater than or equal to BBB+ / Baa1 0.250% 3.125% 2.125% II BBB / Baa2 0.275% 3.250% 2.250% III BBB- / Baa3 0.325% 3.375% 2.375% IV BB+ / Ba1 0.425% 3.625% 2.625% V BB / Ba2 0.500% 3.875% 2.875% VI Less than or equal to BB- / Ba3 0.625% 4.125% 3.125% Upon the Security Release Date, the following pricing table and tiers will take effect: Pricing Tier Credit Rating (S&P/Moody's) Revolving Commitment Fee Applicable Rate For LIBOR Loans and Letter of Credit Fees Applicable Rate for Base Rate Loans I Greater than or equal to BBB+ / Baa1 0.250% 2.625% 1.625% II BBB / Baa2 0.275% 2.750% 1.750% III BBB- / Baa3 0.325% 2.875% 1.875% IV BB+ / Ba1 0.375% 3.125% 2.125% V BB / Ba2 0.425% 3.325% 2.375% As of April 2, 2020, the outstanding balance of the 2018 Term Loan and 2018 DDTL was $434.0 and the carrying value was $432.4 . The outstanding balance of the 2018 Revolver drawn in December 2019 was $800.0 and the carrying amount was $800.0 . On April 30, 2020, the Company repaid the outstanding balance of the 2018 Revolver. As of April 2, 2020, we were in compliance with all applicable covenants under our 2018 Credit Agreement, as amended. Senior Notes 2025 Notes On April 17, 2020, Spirit entered into an Indenture (the “2025 Notes Indenture”), by and among Spirit, the Company and Spirit NC, as guarantors (together with the Company, the “Guarantors”), and The Bank of New York Mellon Trust Company, N.A., as trustee and collateral agent, in connection with Spirit’s offering of $1,200 aggregate principal amount of its 7.500% Senior Secured Second Lien Notes due 2025 (the “2025 Notes”). The 2025 Notes were issued and sold in a private placement to qualified institutional buyers pursuant to Rule 144A under the U.S. Securities Act of 1933, as amended (the “Securities Act”), and in offshore transactions to non-U.S. persons pursuant to Regulation S under the Securities Act. The 2025 Notes mature on April 15, 2025 and bear interest at a rate of 7.500% per year payable semiannually in cash in arrears on April 15 and October 15 of each year. The first interest payment date is October 15, 2020. The 2025 Notes are guaranteed by the Guarantors and secured by certain real property and personal property, including certain equity interests, owned by Spirit and the Guarantors. The 2025 Notes and guarantees are Spirit’s senior secured obligations and will rank equally in right of payment with all of its existing and future senior indebtedness, effectively junior to all of its existing and future first-priority lien indebtedness to the extent of the value of the collateral securing such indebtedness (including indebtedness under the 2018 Credit Agreement and its 2026 Notes), effectively junior to any of its other existing and future indebtedness that is secured by assets that do not constitute collateral for the 2025 Notes to the extent of the value of such assets, and senior in right of payment to any of its existing and future subordinated indebtedness. The 2025 Notes Indenture contains covenants that limit Spirit’s, the Company’s and the Company’s subsidiaries’ ability, subject to certain exceptions and qualifications, to create liens, enter into sale and leaseback transactions and guarantee other indebtedness without guaranteeing the Notes. These covenants are subject to a number of qualifications and limitations. In addition, the 2025 Notes Indenture provides for customary events of default. Floating Rate, 2023, and 2028 Notes On May 30, 2018, Spirit entered into an Indenture (the “2018 Indenture”) by and among Spirit, the Company and The Bank of New York Mellon Trust Company, N.A., as trustee in connection with Spirit’s offering of $300.0 aggregate principal amount of its Senior Floating Rate Notes due 2021 (the “Floating Rate Notes”), $300.0 aggregate principal amount of its 3.950% Senior Notes due 2023 (the “2023 Notes”) and $700.0 aggregate principal amount of its 4.600% Senior Notes due 2028 (the “2028 Notes” and, together with the Floating Rate Notes and the 2023 Notes, the “2018 Notes”). The Company guaranteed Spirit’s obligations under the 2018 Notes on a senior unsecured basis. The Floating Rate Notes bear interest at a rate per annum equal to three-month LIBOR, as determined in the case of the initial interest period, on May 25, 2018, and thereafter at the beginning of each quarterly period as described herein, plus 80 basis points and mature on June 15, 2021. Interest on the Floating Rate Notes is payable on March 15, June 15, September 15 and December 15 of each year, beginning on September 15, 2018. The 2023 Notes bear interest at a rate of 3.950% per annum and mature on June 15, 2023. The 2028 Notes bear interest at a rate of 4.600% per annum and mature on June 15, 2028. Interest on the 2023 Notes and 2028 Notes is payable on June 15 and December 15 of each year, beginning on December 15, 2018. The outstanding balance of the Floating Rate Notes, 2023 Notes, and 2028 Notes was $300.0 , $300.0 , and $700.0 as of April 2, 2020, respectively. The carrying value of the Floating Rate Notes, 2023 Notes, and 2028 Notes was $299.3 , $298.4 , and $694.2 as of April 2, 2020 , respectively. The 2018 Indenture contains covenants that limit Spirit’s, the Company’s and certain of the Company’s subsidiaries’ ability, subject to certain exceptions and qualifications, to create liens without granting equal and ratable liens to the holders of the 2018 Notes and enter into sale and leaseback transactions. These covenants are subject to a number of qualifications and limitations. In addition, the 2018 Indenture provides for customary events of default. 2026 Notes In June 2016, 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. As of April 2, 2020 , the outstanding balance of the 2026 Notes was $300.0 and the carrying value was $297.9 . The Company and Spirit NC guarantee Spirit's obligations under the 2026 Notes on a senior secured basis. On February 24, 2020, Spirit entered into a Second Supplemental Indenture (the “Second Supplemental Indenture”) by and among Spirit, the Company, Spirit NC, and The Bank of New York Mellon Trust Company, N.A. (the “Trustee”), as trustee in connection with the 2026 Notes. Under the Second Supplemental Indenture, the 2026 Noteholders were granted security on an equal and ratable basis with the lenders under the 2018 Credit Agreement (as amended by the February 2020 Amendment) until the security in favor of the lenders under the 2018 Credit Agreement is released. The Supplemental Indenture also added the Spirit NC as an additional guarantor under the indenture governing the 2026 Notes. The guarantee of the Spirit NC will be released upon the release of its guarantee under the 2018 Credit Agreement. On April 17, 2020, Spirit entered into a Third Supplemental Indenture (the “Supplemental Indenture”), by and among Spirit, the Company, Spirit NC and The Bank of New York Mellon Trust Company, N.A., as trustee in connection with the 2025 Notes. Under the Supplemental Indenture, the noteholders were granted security on an equal and ratable basis with the holders of the 2025 Notes.

Pension and Other Post-Retireme

Pension and Other Post-Retirement Benefits	3 Months Ended
	Apr. 02, 2020
Defined Benefit Plan [Abstract]
Pension and Other Post-Retirement Benefits	Pension and Other Post-Retirement Benefits Defined Benefit Plans For the Three Months Ended Components of Net Periodic Pension Expense/(Income) April 2, March 28, Service cost $ 0.2 $ 0.3 Interest cost 8.0 10.1 Expected return on plan assets (17.3 ) (16.7 ) Amortization of net loss — 0.4 Curtailment loss (gain) (2) 33.0 — Special termination benefits (1) 24.7 — Net periodic pension expense (income) $ 48.6 $ (5.9 ) Other Benefits For the Three Months Ended Components of Other Benefit Expense April 2, March 28, Service cost $ 0.3 $ 0.2 Interest cost 0.2 0.3 Amortization of prior service cost (0.2 ) (0.2 ) Amortization of net gain (0.5 ) (0.6 ) Curtailment (gain) loss (0.3 ) — Special termination benefits (1) $ 11.8 $ — Net periodic other benefit expense (income) $ 11.3 $ (0.3 ) (1) Special termination benefits for the three months ending April 2, 2020 is a combination of pension value plan and postretirement medical plan changes offset by a reduction in the Company's net benefit obligation. Special termination benefits, curtailment accounting, and the remeasurement of the pension assets and obligations and retiree medical resulted in a $116.8 and $4.3 impact to OCI, respectively. This impact is included in the Company’s condensed consolidated statements of comprehensive (loss) income. The Company expects to record additional charges in subsequent 2020 quarters related to settlement accounting tied to cash payments made. (2) The Company's Voluntary Retirement Program ("VRP") resulted in an estimated 14% reduction in future working lifetime for the pension value plan and postretirement medical plan resulting in a curtailment accounting charge of $33.0 for the three months ended April 2, 2020 and is included in other (expense) income in the Company's condensed consolidated statements of operations. The components of net periodic pension expense (income) and other benefit expense, other than the service cost component, are included in other (expense) income in the Company's condensed consolidated statements of operations. Employer Contributions The Company expects to contribute zero dollars to the U.S. qualified pension plan and a combined total of approximately $9.4 for the Supplemental Executive Retirement Plan (“SERP”) and post-retirement medical plans in 2020. The Company’s projected contributions to the U.K. pension plan for 2020 are $1.8 . The entire amount contributed can vary based on exchange rate fluctuations.

Stock Compensation

Stock Compensation	3 Months Ended
	Apr. 02, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract]
Stock Compensation	Stock Compensation Holdings has established the stockholder-approved 2014 Omnibus Incentive Plan, as amended (the “Omnibus Plan”) to grant cash and equity awards of Class A Common Stock, par value $0.01 per share (the “Common Stock”), to certain individuals. The Company’s Omnibus Plan was amended in October 2019 to allow for participants to make tax elections with respect to their equity awards. The Company recognized a net total of $9.8 and $7.7 of stock compensation expense for the three months ended April 2, 2020 and March 28, 2019 , respectively. Holdings has established the Long-Term Incentive Plan (the “LTIP”) under the Omnibus Plan to grant equity awards to certain employees of the Company. Generally, specified employees are entitled to receive a long-term incentive award that, for the 2020 year, consisted of the following: • 60% of the award consisted of time-based, service-condition restricted Common Stock that vests in equal installments over a three-year period (the “RS Award”). Values for these awards are based on the value of Common Stock on the grant date. • 20% of the award consisted of performance-based, market-condition restricted Common Stock that vests on the three-year anniversary of the grant date contingent upon TSR compared to the Company’s peers (the “TSR Award”). Values for these awards are initially measured on the grant date using estimated payout levels derived from a Monte Carlo valuation model. • 20% of the award consisted of performance-based, (performance-condition) restricted Common Stock that vests on the three-year anniversary of the grant date contingent upon the Company’s cumulative three-year free cash flow as a percentage of the Company’s cumulative three-year revenues meeting certain pre-established goals (the “FCF Percentage Award”). Values for these awards are based on the dividend adjusted value of Common Stock on the grant date. During the three months ended April 2, 2020 , 324,756 shares, 197,258 shares, and 175,815 shares of Common Stock with aggregate grant date fair values of $16.6 , $6.2 and $9.2 were granted as RS Awards, TSR Awards, and FCF Percentage Awards under the Company’s LTIP. During the three months ended April 2, 2020 , 38,249 shares of Common Stock with aggregate grant date fair values of $2.5 were granted and vested as a result of a union ratification bonus. Additionally, 443,775 shares of Common Stock with an aggregate grant date fair value of $29.7 under the LTIP vested during the three months ended April 2, 2020 .

Income Taxes (Notes)

Income Taxes (Notes)	3 Months Ended
	Apr. 02, 2020
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes The process for calculating the Company’s income tax expense involves estimating actual current taxes due plus assessing temporary differences arising from differing treatment for tax and accounting purposes that are recorded as deferred tax assets and liabilities. Deferred tax assets are periodically evaluated to determine their recoverability. We have reviewed our material deferred tax assets to determine whether or not a valuation allowance was necessary. Based on the Company’s earnings history, in conjunction with other positive and negative evidence, we have determined it is more likely than not that the benefits from the deferred tax assets will be realized and therefore, a valuation allowance is not appropriate at this time. The total net deferred tax asset at April 2, 2020 , and December 31, 2019, was $184.4 and $98.2 , respectively. The difference is primarily due to the creation of deductible temporary differences and utilization of taxable temporary differences within the current year. The Company files income tax returns in all jurisdictions in which it operates. The Company establishes reserves to provide for additional income taxes that may be due upon audit. These reserves are established based on management’s assessment as to the potential exposure attributable to permanent tax adjustments and associated interest. All tax reserves are analyzed quarterly and adjustments made as events occur that warrant modification. For the three months ending April 2, 2020, the amount of income tax benefit that would have been recognized under the expected annual effective tax rate would have exceeded the tax benefit we expect to realize for the full year. Due to this, the loss was limited by the year to date tax benefit that would have been recognized if the year to date loss were the full year anticipated loss (“Loss Limitation Rule”). Essentially, the year to date period was deemed to be the full year for purposes of computing the tax benefit recognized. Certain items, however, continue to be given discrete period treatment and the tax effects for such items are therefore reported in the quarter that an event arises. Events or items that may give rise to discrete recognition include excess tax benefits with respect to share-based compensation, finalizing amounts in income tax returns filed, finalizing audit examinations for open tax years and expiration of statutes of limitations, and changes in tax law. The 35.1% effective tax rate for the three months ended April 2, 2020 differs from the 19.8% effective tax rate for the same period of 2019 primarily due to the benefit generated by state tax credits. In addition, the incorporation of the Loss Limitation Rule and the benefit generated related to the carryback of our 2020 estimated income tax loss as permitted by Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) resulted in increases to the rate which were offset by increases to GILTI and other permanent differences. As the Company is currently reporting a pre-tax loss for the three months ended April 2, 2020, increases to tax expense result in a decrease to the effective tax rate and decreases to tax expense result in an increase to the effective tax rate. The Company's federal audit is effectively complete under the Internal Revenue Service’s Compliance Assurance Process (“

Equity

Equity	3 Months Ended
	Apr. 02, 2020
Stockholders' Equity Note [Abstract]
Equity	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. The Company accounts for treasury stock under the cost method and includes treasury stock as a component of stockholders’ equity. As of April 2, 2020 , no treasury shares have been reissued or retired. During the three month period ended April 2, 2020 , the Company repurchased no shares of its Common Stock. The total authorization amount remaining under the current share repurchase program is approximately $925.0 . Share repurchases are currently on hold pending the outcome of the B737 MAX grounding. The February 2020 Amendment to the 2018 Credit Agreement imposes additional restrictions on the Company’s ability to repurchase shares. The following table sets forth the computation of basic and diluted earnings per share: For the Three Months Ended April 2, 2020 March 28, 2019 Income Shares Per Share Amount Income Shares Per Share Amount Basic EPS (Loss) income available to common stockholders $ (162.9 ) 103.7 $ (1.57 ) $ 163.0 104.0 $ 1.57 (Loss) income allocated to participating securities (0.1 ) — 0.1 0.1 Net (loss) income $ (163.0 ) $ 163.1 Diluted potential common shares 1.2 Diluted EPS Net (loss) income $ (163.0 ) 103.7 $ (1.57 ) $ 163.1 105.3 $ 1.55 Included in the outstanding Common Stock were 1.5 and 1.4 of issued but unvested shares at April 2, 2020 and March 28, 2019 , respectively, which are excluded from the basic EPS calculation. Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Loss is summarized by component as follows: As of As of April 2, 2020 December 31, 2019 Pension $ (142.5 ) $ (53.1 ) Interest swaps (10.4 ) (0.6 ) SERP/Retiree medical 13.0 17.1 Foreign currency impact on long term intercompany loan (16.0 ) (13.1 ) Currency translation adjustment (95.0 ) (59.5 ) Total accumulated other comprehensive loss $ (250.9 ) $ (109.2 ) Amortization or settlement cost recognition of the pension plans’ net gain/(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 $1.0 and $0 for the three months ended April 2, 2020 and March 28, 2019 , respectively.

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	3 Months Ended
	Apr. 02, 2020
Commitments Contingencies And Guarantees [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees Litigation From time to time, the Company is subject to, and is presently involved in, litigation, legal proceedings, or other claims 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, the Company believes that, on a basis of information presently available, none of these items, when finally resolved, will have a material adverse effect on the Company’s long-term financial position or liquidity. On February 10, 2020, February 24, 2020, and March 24, 2020, three separate private securities class action lawsuits were filed against the Company in the U.S. District Court for the Northern District of Oklahoma, its Chief Executive Officer, Tom Gentile III, former chief financial officer, Jose Garcia, and former controller (principal accounting officer), John Gilson. Allegations in each lawsuit include (i) violations of Section 10(b) of the Exchange Act and Rule 10b-5 promulgated thereunder by all defendants, and (ii) violations of Section 20(a) of the Exchange Act against the individual defendants. The facts underlying the complaints relate to the accounting process compliance independent review (the “Accounting Review”) discussed in the Company’s January 30, 2020 press release and described under Management's Discussion and Analysis of Financial Condition and Results of Operations - Accounting Review of the 2019 Form 10-K, and, with respect to the action filed on March 24, 2020, certain disclosures relating to B737 MAX grounding and Spirit’s production rate after the grounding. Prior to the issuance of Company’s January 30, 2020 press release, the Company voluntarily reported to the SEC the determination that, with respect to the third quarter of 2019, the Company did not comply with its established accounting processes related to potential third quarter contingent liabilities received after the quarter-end. The Company has communicated to the SEC that the Accounting Review is substantially complete. On March 24, 2020, the Staff of the SEC Enforcement Division informed the Company that it had determined to close its inquiry without recommending any enforcement action against Spirit. From time to time, in the ordinary course of business and similar to others in the industry, the Company receives 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. The Company reviews such requests and notices and takes appropriate action. Additionally, the Company is 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, the Company is required to participate in certain government investigations regarding environmental remediation actions. Customer and Vendor Claims From time to time the Company receives, or is subject to, customer and vendor claims arising in the ordinary course of business, including, but not limited to, those related to product quality and late delivery. The Company accrues for matters when losses are deemed probable and reasonably estimable. In evaluating matters for accrual and disclosure purposes, we take into consideration multiple factors including without limitation our historical experience with matters of a similar nature, the specific facts and circumstances asserted, the likelihood of an unfavorable outcome, and the severity of any potential loss. Any accruals deemed necessary are reevaluated at least quarterly and updated as matters progress over time. While the final outcome of these types of matters cannot be predicted with certainty, considering, among other things, the factual and legal defenses available, it is the opinion of the Company that, when finally resolved, no current claims will have a material adverse effect on the Company’s long-term financial position or liquidity. However, it is possible that the Company’s results of operations in a period could be materially affected by one or more of these other matters. Guarantees Outstanding guarantees were $19.0 and $21.5 at April 2, 2020 and December 31, 2019 , respectively. Restricted Cash - Collateral Requirements The Company was required to maintain $16.5 and $16.4 of restricted cash as of April 2, 2020 and December 31, 2019 , respectively, related to certain collateral requirements for obligations under its workers’ compensation programs. The 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 its non-employee directors, and its bylaws and certain executive employment agreements include indemnification and advancement provisions. Pursuant to the terms of the bylaws and, with respect to Jose Garcia, his employment agreement, the Company is providing Messrs. Garcia and Gilson advancement of defense costs and provisional indemnity with respect to the three private securities class action lawsuits discussed above. Under the bylaws and any applicable 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. The Company has agreed to indemnify parties for specified liabilities incurred, or that may be incurred, in connection with transactions they have entered into with the Company. The Company is unable to assess the potential number of future claims that may be asserted under these indemnities, nor the amounts thereof (if any). As a result, the Company cannot estimate the maximum potential amount of future payments under these indemnities and therefore, no liability has been recorded. Service and Product Warranties and Extraordinary Rework Provisions for estimated expenses related to service and product warranties and certain extraordinary rework are evaluated on a quarterly basis. These costs are accrued 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 rework is reported in current liabilities and other liabilities on the 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. The amount of the specific provisions recorded against disputed warranty claims was $8.1 as of April 2, 2020 and December 31, 2019 . These specific provisions represent the Company’s best estimate of probable warranty claims. 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 additional charges that exceed these recorded provisions. 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 significant judgment. The amount of the reasonably possible disputed warranty claims in excess of the specific warranty provision was $12.1 as of April 2, 2020 and December 31, 2019 . The following is a roll forward of the service warranty and extraordinary rework balance at April 2, 2020 : Balance, December 31, 2019 $ 64.7 Charges to costs and expenses 1.3 Payouts (0.4 ) Exchange rate (0.4 ) Balance, April 2, 2020 $ 65.2

Other Income (Expense), Net

Other Income (Expense), Net	3 Months Ended
	Apr. 02, 2020
Other Nonoperating Income (Expense) [Abstract]
Other Income (Expense), Net	Other (Expense) Income, Net Other (expense) income, net is summarized as follows: For the Three Months Ended April 2, March 28, Kansas Development Finance Authority bond $ 1.1 $ 1.2 Rental and miscellaneous income — 0.1 Interest income 6.9 3.2 Foreign currency gains (losses) (1) 5.4 (2.0 ) Gain (loss) on foreign currency contract and interest rate swaps 0.1 (15.4 ) Loss on sale of accounts receivable (3.1 ) (4.6 ) Pension (loss) income (2) (59.6 ) 6.5 Other 0.2 — Total $ (49.0 ) $ (11.0 ) (1) Foreign currency gains and losses are due to the impact of movement in foreign currency exchange rates on long-term contractual rights/obligations, as well as cash and both trade and intercompany receivables/payables that are denominated in a currency other than the entity’s functional currency. (2) Pension expense for the three months ended April 2, 2020 includes $69.2 of expenses related to the VRP.

Segment Information

Segment Information	3 Months Ended
	Apr. 02, 2020
Segment Reporting [Abstract]
Segment Information	Segment Information The Company operates in three principal segments: Fuselage Systems, Propulsion Systems, and Wing Systems. Revenue from Boeing represents a substantial portion of the Company's revenues in all segments. Wing Systems also includes significant revenues from Airbus. Approximately 89% of the Company's net revenues for the three months ended April 2, 2020 , 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. Restructuring costs represent corporate level charges related to involuntary workforce reductions and the VRP. 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 Original Equipment Manufacturers (“OEMs”), as well as related spares and maintenance, repairs and overhaul (“MRO”) services and exterior components of rocket systems. The Fuselage Systems segment manufactures products at the Company's facilities in Wichita, Kansas; Biddeford, Maine; Tulsa; Kinston, North Carolina; McAlester, Oklahoma; San Antonio, Texas; and Subang, Malaysia. 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 and internal components to rocket propulsion systems. The Propulsion Systems segment manufactures products at the Company's facility in Wichita, Kansas; Biddeford, Maine; and San Antonio, Texas. The Company’s Wing Systems segment includes development, production and marketing of wings and wing components (including flight control surfaces), and 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 Kinston, North Carolina; Tulsa and McAlester, Oklahoma; San Antonio, Texas; 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 aerostructure production 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 three months ended April 2, 2020 and March 28, 2019 : Three Months Ended April 2, March 28, Segment Revenues Fuselage Systems $ 551.5 $ 1,069.6 Propulsion Systems 225.2 485.7 Wing Systems 291.4 407.9 All Other 9.2 4.6 $ 1,077.3 $ 1,967.8 Segment Operating Income (Loss) Fuselage Systems (1) $ (86.4 ) $ 138.9 Propulsion Systems (2) (5.3 ) 95.5 Wing Systems (3) 13.6 65.8 All Other 1.8 1.2 (76.3 ) 301.4 SG&A (77.4 ) (63.6 ) Research and development (12.3 ) (12.9 ) Unallocated cost of sales (1.5 ) 8.1 Total operating income $ (167.5 ) $ 233.0 (1) includes excess capacity cost of $51.2 related to the B737 MAX production schedule adjustment that began on January 1, 2020, $15.3 abnormal costs of temporary workforce adjustments resulting from the Boeing production suspension which began on March 25, 2020 related to COVID-19, and $30.1 restructuring costs. (2) includes excess capacity cost of $15.8 related to the B737 MAX production schedule adjustment that began on January 1, 2020, $6.2 abnormal costs of temporary workforce adjustments resulting from the Boeing production suspension which began on March 25, 2020 related to COVID-19, and $8.8 restructuring costs. (3)

Restructuring Charges (Notes)

Restructuring Charges (Notes)	3 Months Ended
	Apr. 02, 2020
Restructuring Costs [Abstract]
Restructuring and Related Activities Disclosure [Text Block]	23. Restructuring Costs In March 2019, the B737 MAX fleet was grounded in the U.S. and internationally following the 2018 and 2019 accidents involving two B737 MAX aircraft. At the time, the Company was producing B737 aircraft at a rate of 52 aircraft per month and was expected to increase production to 57 aircraft per month in mid-2019. On April 12, 2019, Boeing and the Company entered into the 2019 MOA relating to the Company's production of aircraft with respect to the B737 program. Under the MOA, the Company was to maintain its delivery rate of 52 shipsets per month with respect to the B737 program following Boeing’s announced temporary adjustment in the production rate from 52 to 42 aircraft per month. The MOA established that all excess shipments (B737 shipsets in excess of Boeing’s rate) would be deemed to be delivered to Boeing “FOB” at the Company's facilities, which would trigger Boeing’s payment obligations for the excess shipsets. On December 19, 2019, the Company was directed by Boeing to stop all B737 MAX deliveries to Boeing effective January 1, 2020, due to Boeing’s announced temporary suspension of B737 MAX production. Accordingly, the Company suspended all B737 MAX production beginning on January 1, 2020. On February 6, 2020, Boeing and the Company entered into the 2020 MOA providing for delivery to Boeing of 216 B737 MAX shipsets in 2020, which represented less than half of the Company’s B737 MAX annualized production rate in 2019. As a result, the Company took actions to align costs to the expected 2020 production levels (restructuring activity). The Company’s planned restructuring activities are documented in a restructuring plan that is approved and controlled by management. The planned activities to align costs to expected production levels following Boeing’s announcement materially affected the scope of operations and manner in which business is conducted by the Company. Restructuring costs under the plan, which are presented separately as a component of operating loss on the consolidated statement of operations, are related to involuntary workforce reductions and the VRP. The total restructuring costs of $42.6 for the three months ended April 2, 2020 includes $31.5 , which is the total amount expected to be incurred for the involuntary termination benefits of approximately 3,200 employees. This amount represents the full cost of the involuntary workforce restructuring activities included in the plan, which has been accrued and substantially paid as of April 2, 2020. The remaining $11.1 of restructuring costs represents the total costs expected to be incurred for the voluntary retirement packages of 207 employees. The cost related to packages under the VRP are generally accrued and charged to earnings when the employee accepts the offer. Of the $11.1 total, $1.2 was paid during the period ended April 2, 2020 and the remaining $9.9 is recorded in the accrued expenses line item on the consolidated balance sheet as of April 2, 2020. The costs of the restructuring plan are included in segment operating margins. The total amount expected to be incurred for each segment is $30.1 for the Fuselage Systems Segment, $8.8 for the Propulsion Systems Segment, and $3.7

Acquisition (Notes)

Acquisition (Notes)	3 Months Ended
	Apr. 02, 2020
Business Combinations [Abstract]
Business Acquisition, Description of Acquired Entity	24. Acquisitions FMI On January 10, 2020 Spirit completed the acquisition of 100% of the outstanding equity of Fiber Materials Inc. (FMI) . The acquisition-date fair value of consideration transferred was $121.6 , which included cash payment to the seller, payment of closing indebtedness, and payment of selling expenses. There is no contingent consideration. Acquiring FMI aligns with the Company's strategic growth objectives to diversify its customer base and expand the current defense business. Founded in 1969 and headquartered in Biddeford, ME, FMI is an industry-leader in the design and manufacture of complex composite solutions that are primarily used in aerospace applications. Over the past 50 years, FMI has developed a portfolio related to its high temperature composites. FMI's main operations focus on multidirectional reinforced composites that enable high-temperature applications such as thermal protection systems, re-entry vehicle nose tips, and rocket motor throats and nozzles. Their unique capabilities have positioned them as a leader in 3D woven carbon-carbon high-temperature materials for hypersonic missiles, which the Department of Defense has identified as a national priority. The acquisition was funded from cash on hand. The Company incurred $1.5 in acquisition-related costs. Acquisition-related expenses were $0.5 for the three months ended April 2, 2020, and are included in SG&A on the condensed consolidated statement of operations. The purchase price has been allocated among assets acquired and liabilities assumed at fair value based on information currently available, with the excess purchase price recorded as goodwill. The Company’s allocation of the purchase price is subject to change on receipt of additional information, including, but not limited to, the finalization of the underlying cash flows used to determine the intangible asset valuations and the Company’s review of FMI’s accounting practices that could potentially result in an adjustment to goodwill or the respective segment allocation of the total goodwill. The Company expects to have sufficient information available to resolve these items before December 31, 2020. The Company has recorded purchase accounting entries on a preliminary basis as follows: At January 10, 2020 Cash and cash equivalents $ 3.5 Accounts receivable 5.3 Inventory 1.9 Contract Assets, short-term 5.6 Prepaid and other current assets 0.5 Equipment and leasehold improvements 12.3 Intangible assets 30.0 Goodwill 76.2 Other noncurrent assets 0.2 Total assets acquired $ 135.5 Accounts payable and accrued liabilities 1.8 Income Tax Payable 1.4 Contract liabilities, short-term 2.2 Accrued payroll and employee benefits 0.6 Other current liabilities 0.2 Deferred income taxes, non-current 7.5 Other noncurrent liabilities 0.2 Total liabilities assumed 13.9 Net assets acquired $ 121.6 The intangible assets included above consist of the following: Amount Amortization Period (in years) Developed technology asset $ 30.0 15 Total intangible assets $ 30.0 15 FMI has developed proprietary know-how over the past 50 years related to its densification and weaving processes. FMI's densification and weaving processes are used to develop specialized composites which can withstand high temperatures and meet the structural requirements set forth by FMI's customers. FMI has developed proprietary designs for 3D and 4D weaving of uncrimped carbon fibers. The densification process utilizes proprietary formulas of heat, pressure, materials, and time to create high density composite solutions at scale. FMI's developed technology results in high strength to weight composites with unmatched density, stability, and heat resistance, which are essential for the mission critical markets it serves. This developed technology is the primary driver of FMI's longstanding, competitive advantage in the markets. FMI is typically engaged with government agencies through purchase orders and does not have any life of program commitments from customers. As a result of FMI’s existing developed technology and incumbent position on previous purchase orders, FMI is positioned to capture future government programs. As such, the developed technology and contract assets were subsumed into one consolidated intangible asset (collectively referred to as the developed technology asset). The developed technology intangible asset is deemed to be the primary revenue-generating identifiable intangible asset acquired in the Transaction. The multi-period excess earnings method ("MPEEM") was used as the approach for estimating the fair value of the developed technology intangible asset which utilizes significant unobservable inputs, or Level 3 inputs, as defined by the fair value hierarchy. The principle behind this method is that the value of the intangible asset is equal to the present value of the after-tax cash flows attributable to the intangible asset only. The analysis included assumptions for projections of revenues and expenses, contributory asset charges, discount rates, and a tax impacts. The goodwill amount of $76.2 recognized is attributable primarily to expected revenue synergies generated by the integration of our products and technologies with those of FMI and intangible assets that do not qualify for separate recognition, such as the assembled workforce of FMI. None of the goodwill is expected to be deductible for income tax purposes. The goodwill is allocated $43.0 to the Fuselage Systems Segment and $33.2 to the Propulsion Systems Segment. This allocation was based upon the fair value of the projected earnings as of the acquisition date. As of April 2, 2020 there were no changes in the recognized amounts of goodwill resulting from the acquisition of FMI. The Company concluded that as a result of FMI’s insulation from the commercial aerospace industry and the increasing demand for its primary products, there was no impact related to the impairment of goodwill resulting from the COVID-19 pandemic as of April 2, 2020. The fair value of accounts receivables acquired is $5.3 , which approximates the gross contractual amount. The Company expects substantially all amounts to be collectible. Prior to the acquisition, the Company did not have a preexisting relationship with FMI. The Company’s consolidated income statement from the acquisition date to the period ending April 2, 2020 includes revenue and earnings of FMI of $10.7 and $1.2 , respectively. The following summary, prepared on a pro forma basis, presents the unaudited consolidated results of operations for the three months ended April 2, 2020 and March 28, 2019, as if the acquisition of FMI had been completed as of the beginning of fiscal 2019, after including in fiscal 2019 any post-acquisition adjustments directly attributable to the acquisition, and after including the impact of adjustments such as amortization of intangible assets, and interest expense on related borrowings and, in each case, the related income tax effects. These amounts have been calculated after substantively applying the Company’s accounting policies. This pro forma presentation does not include any impact of transaction synergies. The pro forma results are not necessarily indicative of our results of operations had the Company owned FMI for the entire periods presented. For the Three Months Ended April 2, March 28, Revenue - as reported $ 1,077.3 $ 1,967.8 Revenue - pro forma 1,078.1 1,975.6 Net (loss) income - as reported $ (163.0 ) $ 163.1 Net (loss) income - pro forma (162.9 ) 163.0 Earnings Per Share - Diluted - as reported $ (1.57 ) $ 1.55 Earnings Per Share - Diluted - pro forma (1.57 ) 1.55 Asco On May 1, 2018, the Company and its wholly-owned subsidiary Spirit AeroSystems Belgium Holdings BVBA (“Spirit Belgium”) entered into a definitive agreement (as amended, the “Asco Purchase Agreement”) with certain private sellers pursuant to which Spirit Belgium will purchase all of the issued and outstanding equity of S.R.I.F. N.V., the parent company of Asco Industries N.V. (“Asco”), a leading supplier of high lift wing structures, mechanical assemblies and major functional components to major OEMs and Tier I suppliers in the global commercial aerospace and military markets subject to certain customary closing adjustments, including foreign currency adjustments (the “Asco Acquisition”). The Asco Purchase Agreement is subject to customary closing conditions, including regulatory approvals. On October 28, 2019, the Company and Spirit Belgium entered into an agreement to amend and restate (the “Asco Amendment”) the Asco Purchase Agreement. The Asco Amendment incorporates amendments to the Purchase Agreement agreed among the Parties to date, and reduces the purchase price for the Asco Acquisition from $604 to $420. In addition, the Asco Amendment reduces the Sellers’ indemnification obligations under the Asco Purchase Agreement to $80 (except with respect to damages resulting or arising from the termination of certain commercial agreements), and removes the closing condition precedent that a “Material Adverse Change” in Asco’s business has not occurred since May 1, 2018. On January 29, 2020, Asco and Spirit entered into an amendment to the Asco Purchase Agreement extending the date upon which the Asco Purchase Agreement will automatically terminate in the event that conditions to the Asco Acquisition are not satisfied or waived is extended from April 4, 2020, to October 1, 2020. In addition, the Amendment changed the closing date for the Acquisition to the last business day of the month that all conditions precedent are satisfied or waived (provided certain notice requirements are met) or as the parties agree. Acquisition-related expenses were $11.0 and $2.8 for the three months ended April 2, 2020 and March 28, 2019, respectively and are included in selling, general and administrative costs on the condensed and consolidated statement of operations. Bombardier On October 31, 2019, Spirit and Spirit AeroSystems Global Holdings Limited (“Spirit UK”), wholly owned subsidiaries of the Company, entered into a definitive agreement (the “Bombardier Purchase Agreement”) with Bombardier Inc., Bombardier Aerospace UK Limited, Bombardier Finance Inc. and Bombardier Services Corporation (collectively, the “Bombardier Sellers”) pursuant to which, subject to the satisfaction or waiver of certain conditions, Spirit UK will acquire the outstanding equity of Short Brothers plc (“Shorts”) and Bombardier Aerospace North Africa SAS, and Spirit will acquire substantially all the assets of the maintenance, repair and overhaul business in Dallas, Texas (collectively, the “Bombardier Acquired Business”) for cash consideration of $500 (the “Bombardier Acquisition”). The Company agreed to procure payment of a special contribution of £100 (approximately $130) to the Shorts pension scheme after closing and has reached a tentative agreement to delay payment of the special contribution to 2021. The Bombardier Acquisition is subject to certain consents, regulatory approvals and customary closing conditions. Closing conditions include, but are not limited to, (i) the absence of certain legal impediments to the consummation of the Bombardier Acquisition, (ii) the receipt of specified third party consents and approvals, including consents from Airbus SE and its subsidiaries, (iii) the receipt of applicable regulatory approvals, and (iv) the absence of a material adverse change to the Bombardier Acquired Business. The Purchase Agreement contains customary representations, warranties and covenants among the parties, including, among others, certain covenants by the Sellers regarding the operation of the Bombardier Acquired Business during the interim period between the execution of the Purchase Agreement and the consummation of the Bombardier Acquisition. The Bombardier Acquisition is not conditioned upon the Company’s receipt of debt financing. Acquisition-related expenses were $1.0

Condensed Consolidating Financi

Condensed Consolidating Financial Information	3 Months Ended
	Apr. 02, 2020
Condensed Financial Information Disclosure [Abstract]
Condensed Consolidating Financial Information	Condensed Consolidating Financial Information The Floating Rate Notes, 2023 Notes, and 2028 Notes (collectively, the "Unsecured Notes") are fully and unconditionally guaranteed on a senior unsecured basis by Holdings. The 2026 Notes are fully and unconditionally guaranteed on a secured senior and second lien basis by Holdings and Spirit NC. The 2025 Notes are fully and unconditionally guaranteed on a secured second lien basis by Holdings and Spirit NC. Together, the Floating Rate Notes, 2023 Notes, 2025 Notes, 2026 Notes, and 2028 Notes shall be referred to as the “Existing Notes.” 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 guarantor of the Existing Notes, as further detailed in Note 15, Debt ; (ii) Spirit, as issuer of the Existing Notes; (iii) Spirit NC, as a guarantor of the 2026 Notes on a secured senior and second lien basis and 2025 Notes on a secured second lien basis; (iv) The Company’s other subsidiaries (the “Non-Guarantor Subsidiaries”), on a combined basis; (v) Consolidating entries and eliminations representing adjustments to (a) eliminate intercompany transactions between or among Holdings, Spirit NC, and the Non-Guarantor Subsidiaries, (b) eliminate the investments in the Company’s subsidiaries, and (c) record consolidating entries; and (vi) Holdings and its subsidiaries on a consolidated basis. Condensed Consolidating Statements of Operations For the Three Months Ended April 2, 2020 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Revenue $ — $ 899.2 $ 111.2 $ 230.9 $ (164.0 ) $ 1,077.3 Operating costs and expenses Cost of sales — 962.7 107.4 206.4 (164.0 ) 1,112.5 Selling, general and administrative 3.5 68.1 0.8 5.0 — 77.4 Restructuring cost — 42.6 — — — 42.6 Research and development — 11.6 0.1 0.6 — 12.3 Total operating costs and expenses 3.5 1,085.0 108.3 212.0 (164.0 ) 1,244.8 Operating (loss) income (3.5 ) (185.8 ) 2.9 18.9 — (167.5 ) Interest expense and financing fee amortization — (32.1 ) — (0.9 ) 0.8 (32.2 ) Other (expense) income, net — (54.3 ) — 6.1 (0.8 ) (49.0 ) (Loss) income before income taxes and equity in net (loss) income of affiliate and subsidiaries (3.5 ) (272.2 ) 2.9 24.1 — (248.7 ) Income tax benefit (provision) 1.2 90.3 (0.7 ) (3.6 ) — 87.2 (Loss) income before equity in net (loss) income of affiliate and subsidiaries (2.3 ) (181.9 ) 2.2 20.5 — (161.5 ) Equity in net (loss) income of affiliate — — — (1.5 ) — (1.5 ) Equity in net (loss) income of subsidiaries (160.7 ) 21.2 — — 139.5 — Net (loss) income (163.0 ) (160.7 ) 2.2 19.0 139.5 (163.0 ) Other comprehensive (loss) income (141.7 ) (141.7 ) — 24.5 117.2 (141.7 ) Comprehensive (loss) income $ (304.7 ) $ (302.4 ) $ 2.2 $ 43.5 $ 256.7 $ (304.7 ) Condensed Consolidating Statements of Operations For the Three Months Ended March 28, 2019 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Revenue $ — $ 1,765.2 116.4 $ 256.8 $ (170.6 ) $ 1,967.8 Operating costs and expenses Cost of sales — 1,500.3 112.7 215.9 (170.6 ) 1,658.3 Selling, general and administrative 2.3 56.5 0.8 4.0 — 63.6 Research and development — 11.4 0.4 1.1 — 12.9 Total operating costs and expenses 2.3 1,568.2 113.9 221.0 (170.6 ) 1,734.8 Operating income (loss) (2.3 ) 197.0 2.5 35.8 — 233.0 Interest expense and financing fee amortization — (18.8 ) — (1.0 ) 1.0 (18.8 ) Other (expense) income, net — (8.4 ) — (1.6 ) (1.0 ) (11.0 ) Income (loss) before income taxes and equity in net income of affiliate and subsidiaries (2.3 ) 169.8 2.5 33.2 — 203.2 Income tax (provision) benefit 0.5 (34.7 ) (0.6 ) (5.3 ) — (40.1 ) Income (loss) before equity in net income of affiliate and subsidiaries (1.8 ) 135.1 1.9 27.9 — 163.1 Equity in net income of affiliate — — — — — — Equity in net income of subsidiaries 164.9 29.8 — — (194.7 ) — Net income 163.1 164.9 1.9 27.9 (194.7 ) 163.1 Other comprehensive income (loss) 10.0 10.0 — 10.4 (20.4 ) 10.0 Comprehensive income (loss) $ 173.1 $ 174.9 1.9 $ 38.3 $ (215.1 ) $ 173.1 Condensed Consolidating Balance Sheet April 2, 2020 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Assets Cash and cash equivalents $ — $ 1,717.0 $ — $ 116.6 $ — $ 1,833.6 Restricted cash — 0.3 — — — 0.3 Accounts receivable, net — 480.1 52.6 301.2 (325.3 ) 508.6 Contract assets, short-term — 328.2 — 52.7 — 380.9 Inventory, net — 832.8 145.0 190.9 — 1,168.7 Other current assets — 129.7 — 4.3 — 134.0 Total current assets — 3,488.1 197.6 665.7 (325.3 ) 4,026.1 Property, plant and equipment, net — 1,773.9 295.7 183.6 — 2,253.2 Right of use assets — 40.0 7.3 0.2 — 47.5 Contract assets, long-term — 3.6 — 6.8 — 10.4 Pension assets, net — 259.0 — 23.6 — 282.6 Deferred income taxes — 192.4 — 0.2 — 192.6 Goodwill — 76.2 — 2.3 — 78.5 Intangible assets, net — 30.6 — — — 30.6 Investment in subsidiary 1,456.4 821.0 — — (2,277.4 ) — Other assets — 152.7 — 113.7 (186.8 ) 79.6 Total assets $ 1,456.4 $ 6,837.5 $ 500.6 $ 996.1 $ (2,789.5 ) $ 7,001.1 Liabilities Accounts payable $ — $ 660.4 $ 225.6 $ 180.0 $ (325.3 ) $ 740.7 Accrued expenses — 251.0 1.1 34.0 — 286.1 Profit sharing — 15.4 — 2.2 — 17.6 Current portion of long-term debt — 50.8 0.2 1.7 — 52.7 Operating lease liabilities, short-term — 5.3 0.6 — — 5.9 Advance payments, short-term — 17.8 — — — 17.8 Contract liabilities, short-term — 166.9 — — — 166.9 Forward loss provision, long-term — 91.5 — — — 91.5 Deferred revenue and other deferred credits, short-term — 17.6 — 0.3 — 17.9 Other current liabilities — 27.2 — 9.8 — 37.0 Total current liabilities — 1,303.9 227.5 228.0 (325.3 ) 1,434.1 Long-term debt — 2,968.9 0.8 94.7 (86.2 ) 2,978.2 Operating lease liabilities, long-term — 34.9 6.7 0.1 — 41.7 Advance payments, long-term — 327.3 — — — 327.3 Pension/OPEB obligation — 50.9 — — — 50.9 Contract liabilities, long-term — 388.9 — — — 388.9 Forward loss provision, long-term — 146.9 — — — 146.9 Deferred grant income liability - non-current — 9.1 — 18.3 — 27.4 Deferred revenue and other deferred credits — 31.4 — 5.4 — 36.8 Deferred income taxes — — — 8.2 — 8.2 Other liabilities — 199.0 — 5.9 (100.6 ) 104.3 Total equity 1,456.4 1,376.3 265.6 635.5 (2,277.4 ) 1,456.4 Total liabilities and stockholders’ equity $ 1,456.4 $ 6,837.5 $ 500.6 $ 996.1 $ (2,789.5 ) $ 7,001.1 Condensed Consolidating Balance Sheet December 31, 2019 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Assets Cash and cash equivalents $ — $ 2,193.3 $ — $ 157.2 $ — $ 2,350.5 Restricted cash — 0.3 — — — 0.3 Accounts receivable, net — 565.4 50.5 250.7 (320.2 ) 546.4 Inventory, net — 786.8 136.8 195.2 — 1,118.8 Contract assets, short-term — 458.8 — 69.5 — 528.3 Other current assets — 93.5 — 5.2 — 98.7 Total current assets — 4,098.1 187.3 677.8 (320.2 ) 4,643.0 Property, plant and equipment, net — 1,773.0 306.3 192.4 — 2,271.7 Right of use assets — 41.2 7.5 0.2 — 48.9 Contract assets, long-term — 6.4 — — — 6.4 Pension assets, net — 424.2 — 24.9 — 449.1 Deferred income taxes — 106.3 — 0.2 — 106.5 Goodwill — — — 2.4 — 2.4 Intangible assets, net — 1.2 — — — 1.2 Investment in subsidiary 1,761.9 838.4 — — (2,600.3 ) — Other assets — 147.6 — 116.0 (186.8 ) 76.8 Total assets $ 1,761.9 $ 7,436.4 $ 501.1 $ 1,013.9 $ (3,107.3 ) $ 7,606.0 Liabilities Accounts payable $ — $ 977.1 $ 226.3 $ 175.1 $ (320.2 ) $ 1,058.3 Accrued expenses — 210.0 0.8 29.4 — 240.2 Profit sharing — 76.9 — 7.6 — 84.5 Current portion of long-term debt — 48.4 0.2 1.6 — 50.2 Operating lease liabilities, short-term — 5.3 0.6 0.1 — 6.0 Advance payments, short-term — 21.6 — — — 21.6 Contract liabilities, short-term — 158.3 — — — 158.3 Forward loss provision, long-term — 83.9 — — — 83.9 Deferred revenue and other deferred credits, short-term — 14.5 — 0.3 — 14.8 Other current liabilities — 29.3 2.1 11.5 — 42.9 Total current liabilities — 1,625.3 230.0 225.6 (320.2 ) 1,760.7 Long-term debt — 2,974.7 0.9 94.7 (86.2 ) 2,984.1 Operating lease liabilities, long-term — 36.0 6.9 0.1 — 43.0 Advance payments, long-term — 333.3 — — — 333.3 Pension/OPEB obligation — 35.7 — — — 35.7 Contract liabilities, long-term — 356.3 — — — 356.3 Forward loss provision, long-term — 163.5 — — — 163.5 Deferred grant income liability - non-current — 9.2 — 19.8 — 29.0 Deferred revenue and other deferred credits — 30.4 — 4.0 — 34.4 Deferred income taxes — — — 8.3 — 8.3 Other liabilities — 190.1 — 6.3 (100.6 ) 95.8 Total equity 1,761.9 1,681.9 263.3 655.1 (2,600.3 ) 1,761.9 Total liabilities and stockholders’ equity $ 1,761.9 $ 7,436.4 $ 501.1 $ 1,013.9 $ (3,107.3 ) $ 7,606.0 Condensed Consolidating Statements of Cash Flows For the Three Months Ended April 2, 2020 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Operating activities Net cash used in operating activities $ — $ (312.5 ) $ 9.8 $ (28.6 ) $ (331.3 ) Investing activities Purchase of property, plant and equipment — (23.4 ) (0.4 ) (7.2 ) — (31.0 ) Acquisition, net of cash acquired — (118.1 ) — — — (118.1 ) Other — 0.3 — 1.5 — 1.8 Net cash used in investing activities — (141.2 ) (0.4 ) (5.7 ) — (147.3 ) Financing activities Customer financing — 10.0 — — — 10.0 Principal payments of debt — (7.0 ) — (0.3 ) — (7.3 ) Payments on term loan — (5.7 ) — — — (5.7 ) Proceeds (payments) from intercompany debt — 9.1 (9.4 ) 0.3 — — Taxes paid related to net share settlement of awards — (13.1 ) — — — (13.1 ) Proceeds (payments) from subsidiary for dividends paid 12.4 (12.4 ) — — — — Dividends Paid (12.4 ) — — — — (12.4 ) Proceeds from issuance of ESPP stock — 1.3 — — — 1.3 Debt issuance costs — (4.8 ) — — — (4.8 ) Net cash provided by (used in) financing activities — (22.6 ) (9.4 ) — — (32.0 ) Effect of exchange rate changes on cash and cash equivalents — — — (6.2 ) (6.2 ) Net decrease in cash and cash equivalents for the period — (476.3 ) — (40.5 ) — (516.8 ) Cash, cash equivalents, and restricted cash, beginning of period — 2,210.0 — 157.2 — 2,367.2 Cash, cash equivalents, and restricted cash, end of period $ — $ 1,733.7 $ — $ 116.7 $ — $ 1,850.4 Condensed Consolidating Statements of Cash Flows For the Three Months Ended March 28, 2019 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Operating activities Net cash provided by operating activities $ — $ 197.4 $ 3.3 $ 41.5 $ — $ 242.2 Investing activities Purchase of property, plant and equipment — (29.3 ) (3.3 ) (8.2 ) — (40.8 ) Acquisition, net of cash acquired — — — — — — Other — 0.1 — — — 0.1 Net cash used in investing activities — (29.2 ) (3.3 ) (8.2 ) — (40.7 ) Financing activities Proceeds from issuance of debt — 250.0 — — — 250.0 Proceeds from revolving credit facility — 100.0 — — — 100.0 Principal payments of debt — (2.4 ) — (0.2 ) — (2.6 ) Proceeds (payments) from intercompany debt — 34.0 — (34.0 ) — — Taxes paid related to net share settlement of awards — (10.0 ) — — — (10.0 ) Proceeds (payments) from subsidiary for purchase of treasury stock 75.0 (75.0 ) — — — — Purchase of treasury stock (75.0 ) — — — — (75.0 ) Proceeds (payments) from subsidiary for dividends paid 12.7 (12.7 ) — — — — Dividends Paid (12.7 ) — — — — (12.7 ) Net cash provided by (used in) financing activities — 283.9 — (34.2 ) — 249.7 Effect of exchange rate changes on cash and cash equivalents — — — (0.3 ) — (0.3 ) Net increase (decrease) in cash and cash equivalents for the period — 452.1 — (1.2 ) — 450.9 Cash, cash equivalents, and restricted cash, beginning of period — 725.5 — 68.6 — 794.1 Cash, cash equivalents, and restricted cash, end of period — 1,177.6 — 67.4 — 1,245.0

Subsequent Event (Notes)

Subsequent Event (Notes)	3 Months Ended
	Apr. 02, 2020
Subsequent Event [Line Items]
Subsequent Events [Text Block]	. Subsequent Events April 2020 Amendment and 2025 Notes On April 13, 2020, the Company entered into the April 2020 Amendment to the 2018 Credit Agreement, which became effective on April 17, 2020. On April 17, 2020, the Company issued the 2025 Notes. For more information on each of these items, please see Note 15, Debt . Rights Plan On April 22, 2020, the Company’s Board of Directors declared a dividend of one right (a “Right”) for each outstanding share of Common Stock held of record at the close of business on May 1, 2020 (the “Record Time”), and adopted a stockholder rights plan, as set forth in the Stockholder Protection Rights Agreement, dated as of April 22, 2020 (the “Rights Agreement”), between the Company and Computershare Inc., as Rights Agent. The Rights will be payable upon the later of the Record Time and the certification by the New York Stock Exchange to the Securities and Exchange Commission that the Rights have been approved for listing and registration. Generally, the Rights may cause substantial dilution to a person or group that acquires 10% (or 20% in the case of a passive institutional investor) or more of the Common Stock unless the Rights are first redeemed or the Rights Agreement is terminated by the Board. While the Rights will not prevent a takeover of the Company, they may discourage a merger, tender or exchange offer or other business combination involving the Company that is not approved by the Board. Nevertheless, the Rights will not interfere with a Board-approved transaction that is in the best interests of the Company and its stockholders because the Rights can be redeemed, or the Rights Agreement terminated, on or prior to the consummation of such a transaction. Prior to exercise, the Rights do not confer voting or dividend rights. Airbus Production Volumes On April 8, 2020, the Company received a supplier letter from Airbus, which provided information related to expected future production rates as a response to the significant disruption to global travel caused by the COVID-19 pandemic. The overall rates announced by Airbus are as follows: ▪ Single-aisle average production volume of 40 APM ▪ A350 average production volume of 6 APM ▪ A330 average production volume of 2 APM These rates are based upon a “mid-term plan” that extends through August of 2020, with additional conclusions regarding the long-term production plan expected to be resolved later in the second quarter. Due to these reduced production volumes, the Company expects lower amounts of revenue and gross profit as deliveries decrease below levels in previous periods. The Company is currently evaluating the potential impact to the A350 program, and based on its preliminary assessment expects to incur an incremental forward loss of approximately $15 to $20 in the second quarter of 2020. As a result of the uncertainty which exists regarding specific production rates, timing, duration and the Company’s actions it may take to recalibrate its cost structure in response to lower production volumes, the amount of forward loss the Company will incur in the second quarter of 2020 may be materially different than the range indicated above. Boeing Production Volumes On April 29, 2020, Boeing announced the following changes to its expected future production rates as a response to the significant disruption to global travel caused by the COVID-19 pandemic. • B737 MAX resume at low rates in 2020, and gradually increase to 31 APM during 2021 • B787 average production volume of 10 APM in 2020, and gradually decrease to 7 APM by 2022 • B777 average production volume will be reduced to 3 APM in 2021 On February 6, 2020, Boeing and the Company entered into the 2020 MOA providing for delivery to Boeing of 216 B737 MAX shipsets in 2020. On May 4, 2020, Boeing and the Company agreed that Spirit will deliver 125 B737 MAX shipsets to Boeing in 2020, rather than the previously announced 216 shipsets. The 125 shipsets to be delivered in 2020 includes shipsets Spirit has delivered to Boeing since January 1, 2020. The Company is working with Boeing to define the specific impacts of these production rate changes, including the timing, duration, model mix, and any potential pricing impacts and anticipates conclusions will be reached later in the second quarter. Due to these reduced production volumes, the Company expects lower amounts of revenue and gross profit as deliveries decrease below levels in previous periods. The Company is currently evaluating the potential impact to the B787 program, and based on its preliminary assessment expects to incur an incremental forward loss of approximately $70 to $90 in the second quarter of 2020 due to the impact of reduced production volumes and the corresponding amount of fixed overhead absorption applied to lower deliveries. Additionally, the Company will evaluate the impact of the expected lower production volumes of the B777 program, which may result in incremental forward losses on other Boeing programs. As a result of the uncertainty which exists regarding our customer’s specific production rates, timing, duration and the Company’s actions it may take to recalibrate its cost structure in response to decisions our customers make, the amount of forward loss the Company will incur in the second quarter of 2020 may be materially different than the range indicated above. Additional Workforce Actions On May 1, 2020, Spirit announced various employment reduction actions in light of customer production rate reductions. Such actions included a voluntary layoff program that was offered to union represented employees in Wichita, KS, a reduction of 1,450 employees in Wichita, KS, and additional reductions at other Spirit locations. Spirit's work on defense programs is expected to continue uninterrupted.

New Accounting Pronouncements (

New Accounting Pronouncements (Policies)	3 Months Ended
	Apr. 02, 2020
Accounting Policies [Abstract]
New Accounting Pronouncements, Policy [Policy Text Block]	. New Accounting Pronouncements In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Rate Reform on Financial Reportin g (“ASU 2020-04”), which provides temporary optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. ASU 2020-04 provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. ASU 2020-04 is effective for all entities as of March 12, 2020 through December 31, 2022, and an entity may elect to apply ASU 2020-04 for contract modifications by Topic or Industry Subtopic as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. An entity may elect to apply ASU 2020-04 to eligible hedging relationships existing as of the beginning of the interim period that includes March 12, 2020 and to new eligible hedging relationships entered into after the beginning of the interim period that includes March 12, 2020. The Company is currently evaluating the potential impact of adopting this guidance on our consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes ("ASU 2019-12”) which modifies FASB Accounting Standards Codification 740 to simplify the accounting for income taxes. ASU 2019-12 is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. The Company is currently evaluating the potential impact of adopting this guidance on our consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-14, Compensation-Retirement Benefits-Defined Benefit Plans-General (Topic 715-20): Disclosure Framework-Changes to the Disclosure Requirements for Defined Benefit Plans

Accounts Receivable and Allow_2

Accounts Receivable and Allowance for Credit Losses Allowance for Credit Losses (Policies)	3 Months Ended
	Apr. 02, 2020
Credit Loss [Abstract]
Credit Loss, Financial Instrument [Text Block]	Allowance for Credit Losses Beginning January 1, 2020, management assesses and records an allowance for credit losses on financial assets within the scope of ASU 2016-13 using the CECL model. Prior periods allowance for credit losses were based on a review of outstanding receivables that are charged off against the allowance after the potential for recovery is considered remote in accordance with legacy GAAP. The amount necessary to adjust the allowance for credit losses to management’s current estimate, as of the reporting date, on these assets is recorded in net income as credit loss expense. All credit losses reported in accordance with ASU 2016-13 were on trade receivables and/or contract assets arising from the Company’s contracts with customers. In determining the appropriate methodology to use within the CECL model for receivables and contract assets arising from the Company’s contracts with customers, the Company considered the risk characteristics of the applicable assets. Spirit segregated the trade receivables and Contract Assets into “pools” of assets at the major customer level. The Company's assessment was based on similarity of risk characteristics shared by these pool of assets. Management observed that risks for collectability, with regard to the trade receivables and contract assets resulting from contracts with customers include: macro level economic conditions that impact all of Spirit’s customers, macro level market conditions that could impact Spirit’s customers in certain aircraft categories, certain customer specific market conditions, certain customer specific economic conditions, certain customer specific administrative conditions. The Company selected a loss-rate method for the CECL model, based on the relationship between historical write-offs of receivables and the underlying sales by major customer. Utilizing this model, a historical loss-rate is applied against the amortized cost of applicable assets, at the time the asset is established. The loss rate reflects the Company’s current estimate of the risk of loss (even when that risk is remote) over the expected remaining contractual life of the assets. The Company's policy is to deduct write-offs from the allowance for credit losses account in the period in which the financial assets are deemed uncollectible. The changes to the allowance for credit losses and related credit loss expense reported for the current period were solely based on the unadjusted results of the CECL model. During the reported period, there have been no significant changes in the factors that influenced management’s current estimate of expected credit losses, nor changes to the Company’s accounting policies or CECL methodology. The beginning balances, current period activity, and ending balances of the allocation for credit losses on accounts receivable and contract assets were not material.

Leases (Policies)

Leases (Policies)	3 Months Ended
	Apr. 02, 2020
Leases [Abstract]
Lessee, Leases [Policy Text Block]	The Company determines if an arrangement is a lease at the inception of a signed agreement. Operating leases are included in in right-of-use (“ROU”) assets (long-term), short-term operating lease liabilities, and long-term operating lease liabilities on the Company’s consolidated balance sheet. Finance leases are included in Property, Plant and Equipment, current maturities of long-term debt, and long-term debt. ROU assets represent the right of the Company to use an underlying asset for the length of the lease term, and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. To determine the present value of lease payments, the Company uses its estimated incremental borrowing rate or the implicit rate, if readily determinable. The estimated incremental borrowing rate is based on information available at the lease commencement date, including any recent debt issuances and publicly available data for instruments with similar characteristics. The ROU asset also includes any lease payments made and excludes lease incentives. The Company's lease terms may include options to extend or terminate the lease and, when it is reasonably certain that an option will be exercised, those options are included in the net present value calculation. Leases with a term of 12 months or less, which are primarily related to automobiles and manufacturing equipment, are not recorded on the balance sheet. The aggregate amount of lease cost for leases with a term of 12 months or less is not material. The Company has lease agreements that include lease and non-lease components, which are generally accounted for separately. For certain leases (primarily related to IT equipment), the Company does account for the lease and non-lease components as a single lease component. A portfolio approach is applied to effectively account for the ROU assets and liabilities for those specific

Other Assets goodwill (Policies

Other Assets goodwill (Policies)	3 Months Ended
	Apr. 02, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets Disclosure [Text Block]	Goodwill is summarized as follows: April 2, December 31, Goodwill - United Kingdom 2.3 2.4 Goodwill - United States (1) 76.2 — Total $ 78.5 $ 2.4 (1) The acquisition of Fiber Materials Inc. ("FMI") on January 10, 2020 resulted in the establishment of $76.2 goodwill. Management used its best judgment to assess the potential impact of COVID-19 pandemic on the valuation of this goodwill as of April 2, 2020. The changes in the allocation of goodwill by reportable segment within the period ended April 2, 2020 reflect the FMI acquisition. The goodwill balance as of December 31, 2019 of $2.4 is allocated to the Wing Systems Segment. The balance as of April 2, 2020 is allocated $43.0 to the Fuselage Systems Segment, $33.2 to the Propulsion Systems Segment, and $2.3 to the Wing Systems Segment. The total goodwill value of $78.5 includes no accumulated impairment loss in any of the periods presented. The change in value from December 31, 2019 to April 2, 2020 for the Europe goodwill item, as seen in the table above, reflects net exchange differences arising during the period. Intangible assets are summarized as follows: April 2, December 31, Intangible assets Patents $ 2.0 $ 2.0 Favorable leasehold interests 2.8 2.8 Developed technology asset (1) 30.0 — Total intangible assets 34.8 4.8 Less: Accumulated amortization - patents (2.0 ) (1.9 ) Accumulated amortization - favorable leasehold interest (1.7 ) (1.7 ) Accumulated amortization - developed technology asset (0.5 ) — Intangible assets, net 30.6 1.2 (1) The acquisition of FMI on January 10, 2020 resulted in the establishment of a $30.0 intangible asset for developed technology as of April 2, 2020. Management used its best judgment to assess the potential impact of COVID-19 pandemic on the valuation of this intangible asset. The amortization for each of the five succeeding years relating to intangible assets currently recorded in the condensed consolidated balance sheet and the weighted average amortization is estimated to be the following as of April 2, 2020: Year Patents Favorable leasehold interest Developed Technology Total remaining in 2020 — 0.1 1.5 1.6 2021 — 0.1 2.0 2.1 2022 — 0.1 2.0 2.1 2023 — 0.1 2.0 2.1 2024 — 0.1 2.0 2.1 2025 — 0.1 2.0 2.1 Weighted average amortization period — 9.5 15.0 14.8

Changes in Estimates Changes in

Changes in Estimates Changes in Estimates (Tables)	3 Months Ended
	Apr. 02, 2020
Accounting Changes and Error Corrections [Abstract]
Schedule of Change in Accounting Estimate [Table Text Block]	Changes in estimates are summarized below: For the Three Months Ended Changes in Estimates April 2, 2020 March 28, 2019 (Unfavorable) Favorable Cumulative Catch-up Adjustment by Segment Fuselage $ (4.0 ) $ (1.2 ) Propulsion (1.5 ) (2.8 ) Wing (2.7 ) (0.2 ) Total (Unfavorable) Favorable Cumulative Catch-up Adjustment $ (8.2 ) $ (4.2 ) Changes in Estimates on Loss Programs (Forward Loss) by Segment Fuselage $ (13.2 ) $ 3.7 Propulsion (3.1 ) 0.5 Wing (3.4 ) 0.5 Total Changes in Estimates (Forward Loss) on Loss Programs $ (19.7 ) $ 4.7 Total Change in Estimate $ (27.9 ) $ 0.5 EPS Impact (diluted per share based upon 2020 forecasted effective tax rate) $ (0.17 ) $ —

Accounts Receivable, net (Table

Accounts Receivable, net (Tables)	3 Months Ended
	Apr. 02, 2020
Accounts Receivable, after Allowance for Credit Loss, Current [Abstract]
Accounts Receivable, Net	Accounts receivable, net consists of the following: April 2, December 31, Trade receivables $ 481.4 $ 515.2 Other 28.1 32.6 Less: allowance for doubtful accounts (0.9 ) (1.4 ) Accounts receivable, net $ 508.6 $ 546.4

Revenue (Tables)

Revenue (Tables) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 1,077.3	$ 1,967.8
Boeing [Member]
Disaggregation of Revenue [Line Items]
Revenues	676.1	1,548.4
Airbus [Member]
Disaggregation of Revenue [Line Items]
Revenues	287.2	329.8
Other Customer [Member]
Disaggregation of Revenue [Line Items]
Revenues	114	89.6
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenues	782.5	1,627.9
UNITED KINGDOM
Disaggregation of Revenue [Line Items]
Revenues	184.1	209.5
Other International [Member]
Disaggregation of Revenue [Line Items]
Revenues	110.7	130.4
Total International [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 294.8	$ 339.9

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Apr. 02, 2020
Inventory Disclosure [Abstract]
Summary Of Inventories	Work-in-process inventory includes direct labor, direct material, overhead, and purchases on contracts for which revenue is recognized at a point in time as well as sub-assembly parts that have not been issued to production on contracts for which revenue is recognized using the input method. For the periods ended April 2, 2020 and December 31, 2019 , work-in-process inventory includes $158.2 and $157.2 , respectively, of costs incurred in anticipation of specific contracts and no impairments were recorded in the period. Product inventory, summarized in the table above, is shown net of valuation reserves of $42.2 and $39.0 as of April 2, 2020 and December 31, 2019 , respectively. Excess capacity and abnormal costs are excluded from inventory and recognized as expense in the period incurred. Cost of sales for the period ended April 2, 2020 includes the impact of $73.4 in excess capacity costs related to the B737 MAX production schedule adjustment that began on January 1, 2020, and the impact of $25.4

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	3 Months Ended
	Apr. 02, 2020
Property, Plant and Equipment [Abstract]
Property, plant and equipment, net	Property, plant and equipment, net consists of the following: April 2, December 31, Land $ 17.2 $ 15.9 Buildings (including improvements) 926.5 924.0 Machinery and equipment 1,989.9 1,941.5 Tooling 1,051.3 1,047.4 Capitalized software 277.3 277.8 Construction-in-progress 178.3 192.8 Total 4,440.5 4,399.4 Less: accumulated depreciation (2,187.3 ) (2,127.7 ) Property, plant and equipment, net $ 2,253.2 $ 2,271.7

Other Assets (Tables)

Other Assets (Tables)	3 Months Ended
	Apr. 02, 2020
Other Assets, Noncurrent [Abstract]
Other Assets	April 2, December 31, Deferred financing Deferred financing costs 45.1 41.7 Less: Accumulated amortization - deferred financing costs (37.5 ) (36.9 ) Deferred financing costs, net 7.6 4.8 Other Supply agreements (1) 10.1 11.5 Equity in net assets of affiliates 6.2 7.7 Restricted cash - collateral requirements 16.5 16.4 Other 39.2 36.4 Total $ 79.6 $ 76.8 (1) Certain payments accounted for as consideration paid by the Company to a customer are being amortized as reductions to net revenues.

Other Assets Intangible Assets

Other Assets Intangible Assets (Tables)	3 Months Ended
	Apr. 02, 2020
Finite-Lived Intangible Assets [Line Items]
Schedule of Finite-Lived Intangible Assets [Table Text Block]	Intangible assets are summarized as follows: April 2, December 31, Intangible assets Patents $ 2.0 $ 2.0 Favorable leasehold interests 2.8 2.8 Developed technology asset (1) 30.0 — Total intangible assets 34.8 4.8 Less: Accumulated amortization - patents (2.0 ) (1.9 ) Accumulated amortization - favorable leasehold interest (1.7 ) (1.7 ) Accumulated amortization - developed technology asset (0.5 ) — Intangible assets, net 30.6 1.2 (1) The acquisition of FMI on January 10, 2020 resulted in the establishment of a $30.0 intangible asset for developed technology as of April 2, 2020. Management used its best judgment to assess the potential impact of COVID-19 pandemic on the valuation of this intangible asset.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	The amortization for each of the five succeeding years relating to intangible assets currently recorded in the condensed consolidated balance sheet and the weighted average amortization is estimated to be the following as of April 2, 2020: Year Patents Favorable leasehold interest Developed Technology Total remaining in 2020 — 0.1 1.5 1.6 2021 — 0.1 2.0 2.1 2022 — 0.1 2.0 2.1 2023 — 0.1 2.0 2.1 2024 — 0.1 2.0 2.1 2025 — 0.1 2.0 2.1 Weighted average amortization period — 9.5 15.0 14.8

Other Assets Goodwill (Tables)

Other Assets Goodwill (Tables)	3 Months Ended
	Apr. 02, 2020
Goodwill [Abstract]
Goodwill Disclosure [Text Block]	Goodwill is summarized as follows: April 2, December 31, Goodwill - United Kingdom 2.3 2.4 Goodwill - United States (1) 76.2 — Total $ 78.5 $ 2.4 (1) The acquisition of Fiber Materials Inc. ("FMI") on January 10, 2020 resulted in the establishment of $76.2 goodwill. Management used its best judgment to assess the potential impact of COVID-19 pandemic on the valuation of this goodwill as of April 2, 2020. The changes in the allocation of goodwill by reportable segment within the period ended April 2, 2020 reflect the FMI acquisition. The goodwill balance as of December 31, 2019 of $2.4 is allocated to the Wing Systems Segment. The balance as of April 2, 2020 is allocated $43.0 to the Fuselage Systems Segment, $33.2 to the Propulsion Systems Segment, and $2.3 to the Wing Systems Segment. The total goodwill value of $78.5 includes no accumulated impairment loss in any of the periods presented. The change in value from December 31, 2019 to April 2, 2020 for the Europe goodwill item, as seen in the table above, reflects net exchange differences arising during the period.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Apr. 02, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	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 the interest rate swaps and foreign currency hedge contracts. Level 3 Unobservable inputs that are supported by little or no market activity and 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.
Carrying Amount And Estimated Fair Value Of Long Term Debt	The following table presents the carrying amount and estimated fair value of long-term debt: April 2, 2020 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value 2018 Term Loan (including current portion) $ 432.4 $ 404.9 (2) $ 438.5 $ 440.1 (2) 2018 Revolver 800.0 800.0 (2) 800.0 800.0 (2) Senior unsecured floating rate notes due 2021 299.3 286.3 (1) 299.1 298.4 (1) Senior unsecured notes due 2023 298.4 254.0 (1) 298.3 307.2 (1) Senior secured notes due 2026 297.9 257.1 (1) 297.8 305.6 (1) Senior unsecured notes due 2028 694.2 576.3 (1) 694.1 734.4 (1) Total $ 2,822.2 $ 2,578.6 $ 2,827.8 $ 2,885.7 (1) Level 1 Fair Value hierarchy (2)

Debt (Tables)

Debt (Tables)	3 Months Ended
	Apr. 02, 2020
Debt Disclosure [Abstract]
Long Term Debt And Capital Lease Obligations Current And Non Current	Total debt shown on the balance sheet is comprised of the following: April 2, 2020 December 31, 2019 Current Noncurrent Current Noncurrent 2018 Term Loan $ 22.7 $ 409.7 $ 22.8 $ 415.7 2018 Revolver — 800.0 — 800.0 Senior unsecured floating rate notes due 2021 — 299.3 — 299.1 Senior unsecured notes due 2023 — 298.4 — 298.3 Senior secured notes due 2026 — 297.9 — 297.8 Senior unsecured notes due 2028 — 694.2 — 694.1 Present value of finance lease obligations 28.2 121.6 25.8 121.3 Other 1.8 57.1 1.6 57.8 Total $ 52.7 $ 2,978.2 $ 50.2 $ 2,984.1

Pension and Other Post-Retire_2

Pension and Other Post-Retirement Benefits (Tables)	3 Months Ended
	Apr. 02, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Change in projected benefit obligations	. Pension and Other Post-Retirement Benefits Defined Benefit Plans For the Three Months Ended Components of Net Periodic Pension Expense/(Income) April 2, March 28, Service cost $ 0.2 $ 0.3 Interest cost 8.0 10.1 Expected return on plan assets (17.3 ) (16.7 ) Amortization of net loss — 0.4 Curtailment loss (gain) (2) 33.0 — Special termination benefits (1) 24.7 — Net periodic pension expense (income) $ 48.6 $ (5.9 ) Other Benefits For the Three Months Ended Components of Other Benefit Expense April 2, March 28, Service cost $ 0.3 $ 0.2 Interest cost 0.2 0.3 Amortization of prior service cost (0.2 ) (0.2 ) Amortization of net gain (0.5 ) (0.6 ) Curtailment (gain) loss (0.3 ) — Special termination benefits (1) $ 11.8 $ — Net periodic other benefit expense (income) $ 11.3 $ (0.3 ) (1) Special termination benefits for the three months ending April 2, 2020 is a combination of pension value plan and postretirement medical plan changes offset by a reduction in the Company's net benefit obligation. Special termination benefits, curtailment accounting, and the remeasurement of the pension assets and obligations and retiree medical resulted in a $116.8 and $4.3 impact to OCI, respectively. This impact is included in the Company’s condensed consolidated statements of comprehensive (loss) income. The Company expects to record additional charges in subsequent 2020 quarters related to settlement accounting tied to cash payments made. (2) The Company's Voluntary Retirement Program ("VRP") resulted in an estimated 14% reduction in future working lifetime for the pension value plan and postretirement medical plan resulting in a curtailment accounting charge of $33.0 for the three months ended April 2, 2020 and is included in other (expense) income in the Company's condensed consolidated statements of operations.

Equity (Tables)

Equity (Tables)	3 Months Ended
	Apr. 02, 2020
Stockholders' Equity Note [Abstract]
Basic and Diluted Earnings per share	The following table sets forth the computation of basic and diluted earnings per share: For the Three Months Ended April 2, 2020 March 28, 2019 Income Shares Per Share Amount Income Shares Per Share Amount Basic EPS (Loss) income available to common stockholders $ (162.9 ) 103.7 $ (1.57 ) $ 163.0 104.0 $ 1.57 (Loss) income allocated to participating securities (0.1 ) — 0.1 0.1 Net (loss) income $ (163.0 ) $ 163.1 Diluted potential common shares 1.2 Diluted EPS Net (loss) income $ (163.0 ) 103.7 $ (1.57 ) $ 163.1 105.3 $ 1.55
Schedule of Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Loss is summarized by component as follows: As of As of April 2, 2020 December 31, 2019 Pension $ (142.5 ) $ (53.1 ) Interest swaps (10.4 ) (0.6 ) SERP/Retiree medical 13.0 17.1 Foreign currency impact on long term intercompany loan (16.0 ) (13.1 ) Currency translation adjustment (95.0 ) (59.5 ) Total accumulated other comprehensive loss $ (250.9 ) $ (109.2 )

Commitments, Contingencies an_2

Commitments, Contingencies and Guarantees (Tables)	3 Months Ended
	Apr. 02, 2020
Commitments Contingencies And Guarantees [Abstract]
Service warranty roll forward	The following is a roll forward of the service warranty and extraordinary rework balance at April 2, 2020 : Balance, December 31, 2019 $ 64.7 Charges to costs and expenses 1.3 Payouts (0.4 ) Exchange rate (0.4 ) Balance, April 2, 2020 $ 65.2

Other Income (Expense), Net (Ta

Other Income (Expense), Net (Tables)	3 Months Ended
	Apr. 02, 2020
Other Nonoperating Income (Expense) [Abstract]
Other Income Expense Net	Other (expense) income, net is summarized as follows: For the Three Months Ended April 2, March 28, Kansas Development Finance Authority bond $ 1.1 $ 1.2 Rental and miscellaneous income — 0.1 Interest income 6.9 3.2 Foreign currency gains (losses) (1) 5.4 (2.0 ) Gain (loss) on foreign currency contract and interest rate swaps 0.1 (15.4 ) Loss on sale of accounts receivable (3.1 ) (4.6 ) Pension (loss) income (2) (59.6 ) 6.5 Other 0.2 — Total $ (49.0 ) $ (11.0 )

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Apr. 02, 2020
Segment Reporting [Abstract]
Segment Information	The following table shows segment revenues and operating income for the three months ended April 2, 2020 and March 28, 2019 : Three Months Ended April 2, March 28, Segment Revenues Fuselage Systems $ 551.5 $ 1,069.6 Propulsion Systems 225.2 485.7 Wing Systems 291.4 407.9 All Other 9.2 4.6 $ 1,077.3 $ 1,967.8 Segment Operating Income (Loss) Fuselage Systems (1) $ (86.4 ) $ 138.9 Propulsion Systems (2) (5.3 ) 95.5 Wing Systems (3) 13.6 65.8 All Other 1.8 1.2 (76.3 ) 301.4 SG&A (77.4 ) (63.6 ) Research and development (12.3 ) (12.9 ) Unallocated cost of sales (1.5 ) 8.1 Total operating income $ (167.5 ) $ 233.0 (1) includes excess capacity cost of $51.2 related to the B737 MAX production schedule adjustment that began on January 1, 2020, $15.3 abnormal costs of temporary workforce adjustments resulting from the Boeing production suspension which began on March 25, 2020 related to COVID-19, and $30.1 restructuring costs. (2) includes excess capacity cost of $15.8 related to the B737 MAX production schedule adjustment that began on January 1, 2020, $6.2 abnormal costs of temporary workforce adjustments resulting from the Boeing production suspension which began on March 25, 2020 related to COVID-19, and $8.8 restructuring costs. (3) includes excess capacity cost of $6.4 related to the B737 MAX production schedule adjustment that began on January 1, 2020, $3.9 abnormal costs of temporary workforce adjustments resulting from the Boeing production suspension which began on March 25, 2020 related to COVID-19, and $3.7 restructuring costs.

Condensed Consolidating Finan_2

Condensed Consolidating Financial Information (Tables)	3 Months Ended
	Apr. 02, 2020
Condensed Financial Information Disclosure [Abstract]
Condensed Income Statement	Condensed Consolidating Statements of Operations For the Three Months Ended April 2, 2020 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Revenue $ — $ 899.2 $ 111.2 $ 230.9 $ (164.0 ) $ 1,077.3 Operating costs and expenses Cost of sales — 962.7 107.4 206.4 (164.0 ) 1,112.5 Selling, general and administrative 3.5 68.1 0.8 5.0 — 77.4 Restructuring cost — 42.6 — — — 42.6 Research and development — 11.6 0.1 0.6 — 12.3 Total operating costs and expenses 3.5 1,085.0 108.3 212.0 (164.0 ) 1,244.8 Operating (loss) income (3.5 ) (185.8 ) 2.9 18.9 — (167.5 ) Interest expense and financing fee amortization — (32.1 ) — (0.9 ) 0.8 (32.2 ) Other (expense) income, net — (54.3 ) — 6.1 (0.8 ) (49.0 ) (Loss) income before income taxes and equity in net (loss) income of affiliate and subsidiaries (3.5 ) (272.2 ) 2.9 24.1 — (248.7 ) Income tax benefit (provision) 1.2 90.3 (0.7 ) (3.6 ) — 87.2 (Loss) income before equity in net (loss) income of affiliate and subsidiaries (2.3 ) (181.9 ) 2.2 20.5 — (161.5 ) Equity in net (loss) income of affiliate — — — (1.5 ) — (1.5 ) Equity in net (loss) income of subsidiaries (160.7 ) 21.2 — — 139.5 — Net (loss) income (163.0 ) (160.7 ) 2.2 19.0 139.5 (163.0 ) Other comprehensive (loss) income (141.7 ) (141.7 ) — 24.5 117.2 (141.7 ) Comprehensive (loss) income $ (304.7 ) $ (302.4 ) $ 2.2 $ 43.5 $ 256.7 $ (304.7 ) Condensed Consolidating Statements of Operations For the Three Months Ended March 28, 2019 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Revenue $ — $ 1,765.2 116.4 $ 256.8 $ (170.6 ) $ 1,967.8 Operating costs and expenses Cost of sales — 1,500.3 112.7 215.9 (170.6 ) 1,658.3 Selling, general and administrative 2.3 56.5 0.8 4.0 — 63.6 Research and development — 11.4 0.4 1.1 — 12.9 Total operating costs and expenses 2.3 1,568.2 113.9 221.0 (170.6 ) 1,734.8 Operating income (loss) (2.3 ) 197.0 2.5 35.8 — 233.0 Interest expense and financing fee amortization — (18.8 ) — (1.0 ) 1.0 (18.8 ) Other (expense) income, net — (8.4 ) — (1.6 ) (1.0 ) (11.0 ) Income (loss) before income taxes and equity in net income of affiliate and subsidiaries (2.3 ) 169.8 2.5 33.2 — 203.2 Income tax (provision) benefit 0.5 (34.7 ) (0.6 ) (5.3 ) — (40.1 ) Income (loss) before equity in net income of affiliate and subsidiaries (1.8 ) 135.1 1.9 27.9 — 163.1 Equity in net income of affiliate — — — — — — Equity in net income of subsidiaries 164.9 29.8 — — (194.7 ) — Net income 163.1 164.9 1.9 27.9 (194.7 ) 163.1 Other comprehensive income (loss) 10.0 10.0 — 10.4 (20.4 ) 10.0 Comprehensive income (loss) $ 173.1 $ 174.9 1.9 $ 38.3 $ (215.1 ) $ 173.1
Condensed Balance Sheet	Condensed Consolidating Balance Sheet April 2, 2020 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Assets Cash and cash equivalents $ — $ 1,717.0 $ — $ 116.6 $ — $ 1,833.6 Restricted cash — 0.3 — — — 0.3 Accounts receivable, net — 480.1 52.6 301.2 (325.3 ) 508.6 Contract assets, short-term — 328.2 — 52.7 — 380.9 Inventory, net — 832.8 145.0 190.9 — 1,168.7 Other current assets — 129.7 — 4.3 — 134.0 Total current assets — 3,488.1 197.6 665.7 (325.3 ) 4,026.1 Property, plant and equipment, net — 1,773.9 295.7 183.6 — 2,253.2 Right of use assets — 40.0 7.3 0.2 — 47.5 Contract assets, long-term — 3.6 — 6.8 — 10.4 Pension assets, net — 259.0 — 23.6 — 282.6 Deferred income taxes — 192.4 — 0.2 — 192.6 Goodwill — 76.2 — 2.3 — 78.5 Intangible assets, net — 30.6 — — — 30.6 Investment in subsidiary 1,456.4 821.0 — — (2,277.4 ) — Other assets — 152.7 — 113.7 (186.8 ) 79.6 Total assets $ 1,456.4 $ 6,837.5 $ 500.6 $ 996.1 $ (2,789.5 ) $ 7,001.1 Liabilities Accounts payable $ — $ 660.4 $ 225.6 $ 180.0 $ (325.3 ) $ 740.7 Accrued expenses — 251.0 1.1 34.0 — 286.1 Profit sharing — 15.4 — 2.2 — 17.6 Current portion of long-term debt — 50.8 0.2 1.7 — 52.7 Operating lease liabilities, short-term — 5.3 0.6 — — 5.9 Advance payments, short-term — 17.8 — — — 17.8 Contract liabilities, short-term — 166.9 — — — 166.9 Forward loss provision, long-term — 91.5 — — — 91.5 Deferred revenue and other deferred credits, short-term — 17.6 — 0.3 — 17.9 Other current liabilities — 27.2 — 9.8 — 37.0 Total current liabilities — 1,303.9 227.5 228.0 (325.3 ) 1,434.1 Long-term debt — 2,968.9 0.8 94.7 (86.2 ) 2,978.2 Operating lease liabilities, long-term — 34.9 6.7 0.1 — 41.7 Advance payments, long-term — 327.3 — — — 327.3 Pension/OPEB obligation — 50.9 — — — 50.9 Contract liabilities, long-term — 388.9 — — — 388.9 Forward loss provision, long-term — 146.9 — — — 146.9 Deferred grant income liability - non-current — 9.1 — 18.3 — 27.4 Deferred revenue and other deferred credits — 31.4 — 5.4 — 36.8 Deferred income taxes — — — 8.2 — 8.2 Other liabilities — 199.0 — 5.9 (100.6 ) 104.3 Total equity 1,456.4 1,376.3 265.6 635.5 (2,277.4 ) 1,456.4 Total liabilities and stockholders’ equity $ 1,456.4 $ 6,837.5 $ 500.6 $ 996.1 $ (2,789.5 ) $ 7,001.1 Condensed Consolidating Balance Sheet December 31, 2019 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Assets Cash and cash equivalents $ — $ 2,193.3 $ — $ 157.2 $ — $ 2,350.5 Restricted cash — 0.3 — — — 0.3 Accounts receivable, net — 565.4 50.5 250.7 (320.2 ) 546.4 Inventory, net — 786.8 136.8 195.2 — 1,118.8 Contract assets, short-term — 458.8 — 69.5 — 528.3 Other current assets — 93.5 — 5.2 — 98.7 Total current assets — 4,098.1 187.3 677.8 (320.2 ) 4,643.0 Property, plant and equipment, net — 1,773.0 306.3 192.4 — 2,271.7 Right of use assets — 41.2 7.5 0.2 — 48.9 Contract assets, long-term — 6.4 — — — 6.4 Pension assets, net — 424.2 — 24.9 — 449.1 Deferred income taxes — 106.3 — 0.2 — 106.5 Goodwill — — — 2.4 — 2.4 Intangible assets, net — 1.2 — — — 1.2 Investment in subsidiary 1,761.9 838.4 — — (2,600.3 ) — Other assets — 147.6 — 116.0 (186.8 ) 76.8 Total assets $ 1,761.9 $ 7,436.4 $ 501.1 $ 1,013.9 $ (3,107.3 ) $ 7,606.0 Liabilities Accounts payable $ — $ 977.1 $ 226.3 $ 175.1 $ (320.2 ) $ 1,058.3 Accrued expenses — 210.0 0.8 29.4 — 240.2 Profit sharing — 76.9 — 7.6 — 84.5 Current portion of long-term debt — 48.4 0.2 1.6 — 50.2 Operating lease liabilities, short-term — 5.3 0.6 0.1 — 6.0 Advance payments, short-term — 21.6 — — — 21.6 Contract liabilities, short-term — 158.3 — — — 158.3 Forward loss provision, long-term — 83.9 — — — 83.9 Deferred revenue and other deferred credits, short-term — 14.5 — 0.3 — 14.8 Other current liabilities — 29.3 2.1 11.5 — 42.9 Total current liabilities — 1,625.3 230.0 225.6 (320.2 ) 1,760.7 Long-term debt — 2,974.7 0.9 94.7 (86.2 ) 2,984.1 Operating lease liabilities, long-term — 36.0 6.9 0.1 — 43.0 Advance payments, long-term — 333.3 — — — 333.3 Pension/OPEB obligation — 35.7 — — — 35.7 Contract liabilities, long-term — 356.3 — — — 356.3 Forward loss provision, long-term — 163.5 — — — 163.5 Deferred grant income liability - non-current — 9.2 — 19.8 — 29.0 Deferred revenue and other deferred credits — 30.4 — 4.0 — 34.4 Deferred income taxes — — — 8.3 — 8.3 Other liabilities — 190.1 — 6.3 (100.6 ) 95.8 Total equity 1,761.9 1,681.9 263.3 655.1 (2,600.3 ) 1,761.9 Total liabilities and stockholders’ equity $ 1,761.9 $ 7,436.4 $ 501.1 $ 1,013.9 $ (3,107.3 ) $ 7,606.0
Condensed Cash Flow Statement	Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Assets Cash and cash equivalents $ — $ 2,193.3 $ — $ 157.2 $ — $ 2,350.5 Restricted cash — 0.3 — — — 0.3 Accounts receivable, net — 565.4 50.5 250.7 (320.2 ) 546.4 Inventory, net — 786.8 136.8 195.2 — 1,118.8 Contract assets, short-term — 458.8 — 69.5 — 528.3 Other current assets — 93.5 — 5.2 — 98.7 Total current assets — 4,098.1 187.3 677.8 (320.2 ) 4,643.0 Property, plant and equipment, net — 1,773.0 306.3 192.4 — 2,271.7 Right of use assets — 41.2 7.5 0.2 — 48.9 Contract assets, long-term — 6.4 — — — 6.4 Pension assets, net — 424.2 — 24.9 — 449.1 Deferred income taxes — 106.3 — 0.2 — 106.5 Goodwill — — — 2.4 — 2.4 Intangible assets, net — 1.2 — — — 1.2 Investment in subsidiary 1,761.9 838.4 — — (2,600.3 ) — Other assets — 147.6 — 116.0 (186.8 ) 76.8 Total assets $ 1,761.9 $ 7,436.4 $ 501.1 $ 1,013.9 $ (3,107.3 ) $ 7,606.0 Liabilities Accounts payable $ — $ 977.1 $ 226.3 $ 175.1 $ (320.2 ) $ 1,058.3 Accrued expenses — 210.0 0.8 29.4 — 240.2 Profit sharing — 76.9 — 7.6 — 84.5 Current portion of long-term debt — 48.4 0.2 1.6 — 50.2 Operating lease liabilities, short-term — 5.3 0.6 0.1 — 6.0 Advance payments, short-term — 21.6 — — — 21.6 Contract liabilities, short-term — 158.3 — — — 158.3 Forward loss provision, long-term — 83.9 — — — 83.9 Deferred revenue and other deferred credits, short-term — 14.5 — 0.3 — 14.8 Other current liabilities — 29.3 2.1 11.5 — 42.9 Total current liabilities — 1,625.3 230.0 225.6 (320.2 ) 1,760.7 Long-term debt — 2,974.7 0.9 94.7 (86.2 ) 2,984.1 Operating lease liabilities, long-term — 36.0 6.9 0.1 — 43.0 Advance payments, long-term — 333.3 — — — 333.3 Pension/OPEB obligation — 35.7 — — — 35.7 Contract liabilities, long-term — 356.3 — — — 356.3 Forward loss provision, long-term — 163.5 — — — 163.5 Deferred grant income liability - non-current — 9.2 — 19.8 — 29.0 Deferred revenue and other deferred credits — 30.4 — 4.0 — 34.4 Deferred income taxes — — — 8.3 — 8.3 Other liabilities — 190.1 — 6.3 (100.6 ) 95.8 Total equity 1,761.9 1,681.9 263.3 655.1 (2,600.3 ) 1,761.9 Total liabilities and stockholders’ equity $ 1,761.9 $ 7,436.4 $ 501.1 $ 1,013.9 $ (3,107.3 ) $ 7,606.0 Condensed Consolidating Statements of Cash Flows For the Three Months Ended April 2, 2020 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Operating activities Net cash used in operating activities $ — $ (312.5 ) $ 9.8 $ (28.6 ) $ (331.3 ) Investing activities Purchase of property, plant and equipment — (23.4 ) (0.4 ) (7.2 ) — (31.0 ) Acquisition, net of cash acquired — (118.1 ) — — — (118.1 ) Other — 0.3 — 1.5 — 1.8 Net cash used in investing activities — (141.2 ) (0.4 ) (5.7 ) — (147.3 ) Financing activities Customer financing — 10.0 — — — 10.0 Principal payments of debt — (7.0 ) — (0.3 ) — (7.3 ) Payments on term loan — (5.7 ) — — — (5.7 ) Proceeds (payments) from intercompany debt — 9.1 (9.4 ) 0.3 — — Taxes paid related to net share settlement of awards — (13.1 ) — — — (13.1 ) Proceeds (payments) from subsidiary for dividends paid 12.4 (12.4 ) — — — — Dividends Paid (12.4 ) — — — — (12.4 ) Proceeds from issuance of ESPP stock — 1.3 — — — 1.3 Debt issuance costs — (4.8 ) — — — (4.8 ) Net cash provided by (used in) financing activities — (22.6 ) (9.4 ) — — (32.0 ) Effect of exchange rate changes on cash and cash equivalents — — — (6.2 ) (6.2 ) Net decrease in cash and cash equivalents for the period — (476.3 ) — (40.5 ) — (516.8 ) Cash, cash equivalents, and restricted cash, beginning of period — 2,210.0 — 157.2 — 2,367.2 Cash, cash equivalents, and restricted cash, end of period $ — $ 1,733.7 $ — $ 116.7 $ — $ 1,850.4 Condensed Consolidating Statements of Cash Flows For the Three Months Ended March 28, 2019 Holdings Spirit Spirit NC Non-Guarantor Subsidiaries Consolidating Adjustments Total Operating activities Net cash provided by operating activities $ — $ 197.4 $ 3.3 $ 41.5 $ — $ 242.2 Investing activities Purchase of property, plant and equipment — (29.3 ) (3.3 ) (8.2 ) — (40.8 ) Acquisition, net of cash acquired — — — — — — Other — 0.1 — — — 0.1 Net cash used in investing activities — (29.2 ) (3.3 ) (8.2 ) — (40.7 ) Financing activities Proceeds from issuance of debt — 250.0 — — — 250.0 Proceeds from revolving credit facility — 100.0 — — — 100.0 Principal payments of debt — (2.4 ) — (0.2 ) — (2.6 ) Proceeds (payments) from intercompany debt — 34.0 — (34.0 ) — — Taxes paid related to net share settlement of awards — (10.0 ) — — — (10.0 ) Proceeds (payments) from subsidiary for purchase of treasury stock 75.0 (75.0 ) — — — — Purchase of treasury stock (75.0 ) — — — — (75.0 ) Proceeds (payments) from subsidiary for dividends paid 12.7 (12.7 ) — — — — Dividends Paid (12.7 ) — — — — (12.7 ) Net cash provided by (used in) financing activities — 283.9 — (34.2 ) — 249.7 Effect of exchange rate changes on cash and cash equivalents — — — (0.3 ) — (0.3 ) Net increase (decrease) in cash and cash equivalents for the period — 452.1 — (1.2 ) — 450.9 Cash, cash equivalents, and restricted cash, beginning of period — 725.5 — 68.6 — 794.1 Cash, cash equivalents, and restricted cash, end of period — 1,177.6 — 67.4 — 1,245.0

Changes in Estimates (Details)

Changes in Estimates (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Change In Estimate [Line Items]
Changes in Contract Estimates, aggregate, Affecting earnings from Continuing Operations, per Share diluted	$ (0.17)	$ 0
Change In Accounting Estimate, aggregate	$ (27.9)	$ 0.5
Cumulative catch-up adjustment [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(8.2)	(4.2)
Forward Loss [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(19.7)	4.7
Fuselage Systems [Member] | Cumulative catch-up adjustment [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(4)	(1.2)
Fuselage Systems [Member] | Forward Loss [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(13.2)	3.7
Wing Systems [Member] | Cumulative catch-up adjustment [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(2.7)	(0.2)
Wing Systems [Member] | Forward Loss [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(3.4)	0.5
Propulsion Systems [Member] | Cumulative catch-up adjustment [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	(1.5)	(2.8)
Propulsion Systems [Member] | Forward Loss [Member]
Change In Estimate [Line Items]
Change in Accounting Estimate - Contract Accounting	$ (3.1)	$ 0.5

Accounts Receivable, net (Detai

Accounts Receivable, net (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019
Accounts Receivable, after Allowance for Credit Loss, Current [Abstract]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	$ 718.1
Trade receivables	481.4		$ 515.2
Other	28.1		32.6
Less: allowance for doubtful accounts	(0.9)		(1.4)
Accounts receivable, net	508.6		$ 546.4
Gain (Loss) on Sale of Accounts Receivable	$ 3.1	$ 4.6

Contract with customer, asset_2

Contract with customer, asset and liability (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,077.3	$ 1,967.8
Disaggregation of Revenue [Table Text Block]	Disaggregation of Revenue The Company disaggregates revenue based on the method of measuring satisfaction of the performance obligation either over time or at a point in time, based upon the location where products and services are transferred to the customer, and based upon major customer. The Company’s principal operating segments and related revenue are noted in Note 22, Segment Information . The following tables show disaggregated revenues for the three months ended April 2, 2020 and March 28, 2019 : For the Three Months Ended Revenue April 2, March 28, Contracts with performance obligations satisfied over time $ 605.9 $ 1,479.7 Contracts with performance obligations satisfied at a point in time 471.4 488.1 Total Revenue $ 1,077.3 $ 1,967.8 The following table disaggregates revenue by major customer: For the Three Months Ended Customer April 2, March 28, Boeing $ 676.1 $ 1,548.4 Airbus 287.2 329.8 Other 114.0 89.6 Total Revenue $ 1,077.3 $ 1,967.8 The following table disaggregates revenue based upon the location where control of products are transferred to the customer: For the Three Months Ended Location April 2, March 28, United States $ 782.5 $ 1,627.9 International United Kingdom 184.1 209.5 Other 110.7 130.4 Total International 294.8 339.9 Total Revenue $ 1,077.3 $ 1,967.8
Contract with Customer, Liability, Revenue Recognized	$ 33.1	19.4
Contract with Customer, Asset, before Allowance for Credit Loss	391.3	582.2	$ 534.7	$ 523.5
change in contract asset	(143.4)	58.7
Contract with Customer, Liability	(555.8)	(532.4)	(514.6)	(527.7)
change in contract liability	(41.2)	(4.7)
Contract with Customer, Asset, after Allowance for Credit Loss	(164.5)	49.8	$ (20.1)	$ 4.2
change in net contract asset	(184.6)	54
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenues	605.9	1,479.7
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 471.4	$ 488.1

Revenue (Details)

Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Disaggregation of Revenue [Table Text Block]	Disaggregation of Revenue The Company disaggregates revenue based on the method of measuring satisfaction of the performance obligation either over time or at a point in time, based upon the location where products and services are transferred to the customer, and based upon major customer. The Company’s principal operating segments and related revenue are noted in Note 22, Segment Information . The following tables show disaggregated revenues for the three months ended April 2, 2020 and March 28, 2019 : For the Three Months Ended Revenue April 2, March 28, Contracts with performance obligations satisfied over time $ 605.9 $ 1,479.7 Contracts with performance obligations satisfied at a point in time 471.4 488.1 Total Revenue $ 1,077.3 $ 1,967.8 The following table disaggregates revenue by major customer: For the Three Months Ended Customer April 2, March 28, Boeing $ 676.1 $ 1,548.4 Airbus 287.2 329.8 Other 114.0 89.6 Total Revenue $ 1,077.3 $ 1,967.8 The following table disaggregates revenue based upon the location where control of products are transferred to the customer: For the Three Months Ended Location April 2, March 28, United States $ 782.5 $ 1,627.9 International United Kingdom 184.1 209.5 Other 110.7 130.4 Total International 294.8 339.9 Total Revenue $ 1,077.3 $ 1,967.8
Revenues	$ 1,077.3	$ 1,967.8
Remaining in Current Year [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,955.1
2021 [Member] [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,716.9
2022 [Member] [Member] [Domain]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,806.7
2021 and after [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,767.4
Transferred over Time [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	605.9	1,479.7
Transferred at Point in Time [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	$ 471.4	$ 488.1

Inventory (Details)

Inventory (Details) - USD ($)	3 Months Ended
	Apr. 02, 2020	Dec. 31, 2019
Summary Of Inventories [Abstract]
Raw materials	$ 321,000,000	$ 253,100,000
Work-in-process	803,100,000	822,800,000
Finished goods	16,800,000	14,500,000
Product inventory	1,140,900,000	1,090,400,000
Capitalized pre-production	27,800,000	28,400,000
Total inventory, net	1,168,700,000	1,118,800,000
Inventory Valuation Reserves	42,200,000	39,000,000
Costs Incurred in Anticipation of Contracts	158,200,000	$ 157,200,000
Cost, Overhead	73.4
Abnormal Costs- COVID19 production suspension	$ 25.4

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Millions	Apr. 02, 2020	Dec. 31, 2019
Property, plant and equipment, net
Land	$ 17.2	$ 15.9
Buildings (including improvements)	926.5	924
Machinery and equipment	1,989.9	1,941.5
Tooling	1,051.3	1,047.4
Capitalized software	277.3	277.8
Construction-in-progress	178.3	192.8
Total	4,440.5	4,399.4
Less: accumulated depreciation	(2,187.3)	(2,127.7)
Property, plant and equipment, net	$ 2,253.2	$ 2,271.7

Property, Plant and Equipment_3

Property, Plant and Equipment (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Property Plant And Equipment Textuals [Abstract]
Repair and maintenance costs	$ 30.5	$ 35.6
Depreciation expense related to capitalized software	$ 4.3	$ 4.3

Leases (Details)

Leases (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019
Lessee Disclosure [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	10 years 1 month 6 days		10 years 2 months 12 days
Finance Lease, Weighted Average Remaining Lease Term	6 years 2 months 12 days		6 years 6 months
Assets and Liabilities, Lessee [Abstract]
Operating Lease, Liability, Current	$ 5.9		$ 6
Operating Lease, Liability, Noncurrent	41.7		43
Operating Lease, Liability	47.6
finance lease, Right-of-Use Asset, gross	194.8		165.5
Finance Lease, RIght-of-Use Asset, Accumulated Amortization	(28.9)		(23.5)
Finance Lease, Right-of-Use Asset	165.9		$ 142
Finance Lease, Liability	149.8
Lessee, Operating Lease, Lease Not yet Commenced, Description	2.8
Lessee, Finance Lease, Lease Not yet Commenced, Description	$ 51.9
Operating Lease, Weighted Average Discount Rate, Percent	5.60%		5.60%
Finance Lease, Weighted Average Discount Rate, Percent	4.20%		4.30%
Finance Lease, Liability, Payment, Due [Abstract]
Finance Lease, Liability, Payments, Remainder of Fiscal Year	$ 25.3
Finance Lease, Liability, Payments, Due Year Two	33.4
Finance Lease, Liability, Payments, Due Year Three	29.6
Finance Lease, Liability, Payments, Due Year Four	25.5
Finance Lease, Liability, Payments, Due Year Five	20
Finance Lease, Liability, Payments, Due after Year Five	37.1
Finance Lease, Liability, Payment, Due	170.9
Lease Imputed Interest Due- Financing	(21.1)
Cash Flow, Operating Activities, Lessee [Abstract]
Operating lease cost	2.2	$ 2.2
Finance Lease, Interest Payment on Liability	1.6	0.4
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	0.2	0.1
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	6.4
Lessee, Operating Lease, Liability, Payments, Due Year Two	7.5
Lessee, Operating Lease, Liability, Payments, Due Year Three	7.1
Lessee, Operating Lease, Liability, Payments, Due Year Four	6.1
Lessee, Operating Lease, Liability, Payments, Due Year Five	5.6
Lessee, Operating Lease, Liability, Payments, Due after Year Five	30.3
Lessee, Operating Lease, Liability, Payments, Due	63
Lease Imputed Interest Due- Operating	(15.4)
Lease, Cost [Abstract]
Operating Lease, Cost	2.2	2.2
Finance Lease, Right-of-Use Asset, Amortization	5.8	1.8
Finance Lease, Interest Expense	1.6	0.4
Lease, Cost	9.6	4.4
Cash Flow, Financing Activities, Lessee [Abstract]
Finance Lease, Principal Payments	$ 6.7	$ 1.8

Other Assets (Details)

Other Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Dec. 31, 2019	Mar. 28, 2019	Dec. 31, 2018
Other Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	$ 34.8	$ 4.8
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	1.6
Finite-Lived Intangible Assets, Amortization Expense, Year Two	2.1
Finite-Lived Intangible Assets, Amortization Expense, Year Three	2.1
Finite-Lived Intangible Assets, Amortization Expense, Year Four	2.1
Finite-Lived Intangible Assets, Amortization Expense, Year Five	2.1
Finite-Lived Intangible Assets, Amortization Expense, Year Six	2.1
Intangible assets
Deferred financing costs, net	7.6	4.8
Goodwill - Europe	78.5	2.4
Equity in net assets of affiliates	6.2	7.7
Customer Supply Agreement	10.1	11.5
Restricted Cash, Noncurrent	16.5	16.4	$ 16.3	$ 20.2
Other	39.2	36.4
Total	79.6	76.8
Intangible Assets, Net (Excluding Goodwill)	$ 30.6	1.2
Weighted Average Amortization Period Intangible Assets	P14Y9M18D
Patents [Member]
Other Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	$ 2	2
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	0
Finite-Lived Intangible Assets, Amortization Expense, Year Two	0
Finite-Lived Intangible Assets, Amortization Expense, Year Three	0
Finite-Lived Intangible Assets, Amortization Expense, Year Four	0
Finite-Lived Intangible Assets, Amortization Expense, Year Five	0
Finite-Lived Intangible Assets, Amortization Expense, Year Six	0
Intangible assets
Less: Accumulated amortization	2	1.9
Favorable Leasehold [Member]
Other Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	2.8	2.8
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	0.1
Finite-Lived Intangible Assets, Amortization Expense, Year Two	0.1
Finite-Lived Intangible Assets, Amortization Expense, Year Three	0.1
Finite-Lived Intangible Assets, Amortization Expense, Year Four	0.1
Finite-Lived Intangible Assets, Amortization Expense, Year Five	0.1
Finite-Lived Intangible Assets, Amortization Expense, Year Six	0.1
Intangible assets
Less: Accumulated amortization	$ 1.7	1.7
Weighted Average Amortization Period Intangible Assets	P9Y6M
Debt issuance costs [Member]
Intangible assets
Deferred financing costs	$ 45.1	41.7
Less: Accumulated amortization-deferred financing costs	(37.5)	(36.9)
Developed Technology [Member]
Other Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	30	0
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	1.5
Finite-Lived Intangible Assets, Amortization Expense, Year Two	2
Finite-Lived Intangible Assets, Amortization Expense, Year Three	2
Finite-Lived Intangible Assets, Amortization Expense, Year Four	2
Finite-Lived Intangible Assets, Amortization Expense, Year Five	2
Finite-Lived Intangible Assets, Amortization Expense, Year Six	2
Intangible assets
Less: Accumulated amortization	$ 0.5	$ 0
Weighted Average Amortization Period Intangible Assets	P15Y

Other Assets (Details Textuals)

Other Assets (Details Textuals) - USD ($) $ in Millions	Apr. 02, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill	$ 78.5	$ 2.4
Spirit Europe Goodwill [Member]
Goodwill [Line Items]
Goodwill	2.3	2.4
FMI Goodwill [Member] [Member]
Goodwill [Line Items]
Goodwill	76.2	0
Wing Systems [Member]
Goodwill [Line Items]
Goodwill	2.3	$ 2.4
FMI [Member]
Goodwill [Line Items]
Goodwill	76.2
FMI [Member] | Fuselage Systems [Member]
Goodwill [Line Items]
Goodwill	43
FMI [Member] | Propulsion Systems [Member]
Goodwill [Line Items]
Goodwill	$ 33.2

Advance Payments and Deferred_2

Advance Payments and Deferred Revenue/Credits (Details) $ in Millions	Apr. 02, 2020USD ($)
advance payments [Line Items]
Customer advances- B787 program	$ 212.1
Total Payment [Member]
advance payments [Line Items]
Customer advances- B737 program	123
Total Payment [Member]
advance payments [Line Items]
Customer advances- B737 program	225
Production Stabilization [Member]
advance payments [Line Items]
Customer advances- B737 program	70
To be repaid in 2021 [Member]
advance payments [Line Items]
Customer advances- B737 program	10
Prepayment of shipset deliveries [Member]
advance payments [Line Items]
Customer advances- B737 program	$ 155

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	Apr. 02, 2020	Dec. 31, 2019	Jun. 27, 2019
Carrying amount and estimated fair value of long term debt
Carrying Amount	$ 2,822.2	$ 2,827.8
Fair Value	2,578.6	2,885.7
Long-term Line of Credit, Noncurrent	800	800	$ 800
Lines of Credit, Fair Value Disclosure		800	$ 800
Secured Debt Term A [Member]
Debt Instrument [Line Items]
Secured Debt, Current	22.7	22.8
Secured Long-term Debt, Noncurrent	409.7	415.7
Carrying amount and estimated fair value of long term debt
Carrying Amount	432.4	438.5
Fair Value	404.9	440.1
Senior unsecured notes due 2022 [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	286.3	298.4
Senior Notes, Noncurrent		299.1
Senior Unsecured Notes Due 2023 [Domain]
Carrying amount and estimated fair value of long term debt
Fair Value	254	307.2
Senior Notes, Noncurrent	298.4	298.3
Senior Unsecured Notes Due 2026 [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	257.1	305.6
Senior Notes, Noncurrent	297.9	297.8
SeniorUnsecuredNotesDue2028 [Member] [Member]
Carrying amount and estimated fair value of long term debt
Fair Value	$ 576.3	734.4
Senior Notes, Noncurrent		$ 694.1

Derivative and Hedging Activi_2

Derivative and Hedging Activities (Details 1) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	$ 13.7
Maximum Length of Time Hedged in Cash Flow Hedge	3 years
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	$ 12.9	$ 0
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate	1.815%

Derivative and Hedging Activi_3

Derivative and Hedging Activities (Details Textual) - USD ($)	3 Months Ended
	Apr. 02, 2020	Dec. 31, 2019
Derivatives Fair Value [Line Items]
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 0.1
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	5.7
Derivative, Fair Value, Net	0	$ 100,000
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	$ 0

Debt (Details)

Debt (Details) - USD ($)	Apr. 02, 2020	Dec. 31, 2019	Jun. 27, 2019
Debt Disclosure [Abstract]
Outstanding Balance Term Loan	$ 434
Carrying Value Term Loan	432.4
Outstanding Balance Revolver	800
Carrying Value 2018 Revolver	800
Line of Credit, Current	0	$ 0
Long-term Line of Credit, Noncurrent	800,000,000	800,000,000	$ 800,000,000
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Capital Lease Obligations, Current	28,200,000	25,800,000
Capital Lease Obligations, Noncurrent	121,600,000	121,300,000
Other Long-term Debt, Current	1,800,000	1,600,000
Other Long-term Debt, Noncurrent	57,100,000	57,800,000
Long-term Debt and Lease Obligation, Current	52,700,000	50,200,000
Long-term Debt and Lease Obligation	2,978,200,000	2,984,100,000
Secured Debt Term A [Member]
Debt Disclosure [Abstract]
Secured Debt, Current	22,700,000	22,800,000
Senior unsecured notes due 2022 [Member]
Debt Disclosure [Abstract]
Debt Instrument, Face Amount	300,000,000
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Senior Notes, Noncurrent		299,100,000
SeniorUnsecuredFloatingRateNotes [Member]
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Senior Notes, Noncurrent	299,300,000	299,100,000
Senior Unsecured Notes Due 2023 [Domain]
Debt Disclosure [Abstract]
Debt Instrument, Face Amount	300,000,000
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Senior Notes, Current	0	0
Senior Notes, Noncurrent	298,400,000	298,300,000
SeniorUnsecuredNotesDue2028 [Member] [Member]
Debt Disclosure [Abstract]
Debt Instrument, Face Amount	700,000,000
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Senior Notes, Noncurrent		694,100,000
Senior Unsecured Notes Due 2026 [Member]
Debt Disclosure [Abstract]
Debt Instrument, Face Amount	300,000,000
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Senior Notes, Current	0	0
Senior Notes, Noncurrent	297,900,000	297,800,000
Senior Unsecured Notes Due 2028 [Member]
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Senior Notes, Current	0	0
Senior Notes, Noncurrent	694,200,000	694,100,000
Total Debt [Member]
Long Term Debt And Capital Lease Obligations Current And Non Current [Abstract]
Long-term Debt and Lease Obligation, Current	52,700,000	50,200,000
Long-term Debt and Lease Obligation	$ 2,978,200,000	$ 2,984,100,000

Debt (Details Textual)

Debt (Details Textual) - USD ($)	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019
Debt Instrument [Line Items]
Outstanding Balance Term Loan	$ 434
Proceeds from (Payments for) Other Financing Activities	10,000,000	$ 0
Optional Revolver Commitment	750,000,000
Restricted Cash and Cash Equivalents	300,000		$ 300,000
Proceeds from Issuance of Senior Long-term Debt		250,000,000
Proceeds from Lines of Credit	0	$ 100,000,000
Carrying Value Term Loan	432.4
Long-term Debt	2,822,200,000		2,827,800,000
SeniorUnsecuredNotesDue2028 [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	700,000,000
Senior Notes	694,200,000
2018 Amended Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	1,256,000,000
Senior unsecured notes due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	300,000,000
Senior Notes	299,300,000
Senior Unsecured Notes Due 2023 [Domain]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	300,000,000
Senior Notes	298,400,000
Senior Notes, Current	0		0
Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	300,000,000
Senior Notes	297,900,000
Senior Notes, Current	0		0
2018 Revolver [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	800,000,000
2018 Term Loan A [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	206,000,000
Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 250,000,000
2018 Revolver, 2018 Term Loan, Delayed Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate Terms	Each of the 2018 Revolver, the 2018 Term Loan and the 2018 DDTL matures on July 12, 2023, and prior to the February 2020 Amendment (as defined below), bears interest, at Spirit’s option, ranging between LIBOR plus 1.125% and LIBOR plus 1.875% (or between base rate plus 0.125% and base rate plus 0.875%, as applicable) based on Spirit’s senior unsecured ratings provided by Standard & Poor’s Financial Services LLC (“S&P”) and/or Moody’s Investors Service, Inc. (“Moody’s”)
Debt Instrument, Payment Terms	The principal obligations under the 2018 DDTL are to be repaid in equal quarterly installments of $3.1, subject to adjustments for any extension of the availability period of the 2018 DDTL, commencing with the fiscal quarter ending June 27, 2019, and with the balance due at maturity of the 2018 DDTL.
2020 Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 375,000,000
Senior unsecured term loan A [Member]
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal	2,600,000
Secured Debt Term A [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 432,400,000		$ 438,500,000

Pension and Other Post Retireme

Pension and Other Post Retirement Benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Pension And Other Post Retirement Benefits Textuals [Abstract]
Defined Benefit Plan Estimated Future Employer Contributions Remainder Of Year	$ 9.4
Expected UK Pension Plan Contribution For The Year	1.8
Defined Benefit Plans [Member]
Pension [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax	116.8
Pension and Other Post-Retirement Benefits
Service cost	(0.2)	$ (0.3)
Interest cost	(8)	(10.1)
Expected return on plan assets	(17.3)	(16.7)
Amortization of net loss	0	0.4
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	24.7	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment	33	0
Net periodic pension income	48.6	(5.9)
Other Benefits [Member]
Pension [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax	(4.3)
Pension and Other Post-Retirement Benefits
Service cost	(0.3)	(0.2)
Interest cost	(0.2)	(0.3)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(0.2)	(0.2)
Amortization of net loss	(0.5)	(0.6)
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	11.8	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment	(0.3)	0
Net periodic pension income	$ 11.3	$ (0.3)

Stock Compensation (Details)

Stock Compensation (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company recognized total stock compensation expense, net of forfeitures	$ 9.8	$ 7.7
LTIA AND Prior Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company recognized total stock compensation expense, net of forfeitures	$ 9.8	$ 7.7
Class A [Member] | Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	443,775
Grant date value of shares vested	$ 29.7
Class A [Member] | Board of Directors Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	38,249
Fair Value Of Shares Granted	$ 2.5
Class A [Member] | Market Based LTIA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	197,258
Fair Value Of Shares Granted	$ 6.2
Class A [Member] | Service Based LTIA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	324,756
Fair Value Of Shares Granted	$ 16.6
Class A [Member] | Performance Based LTIA [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	175,815
Fair Value Of Shares Granted	$ 9.2

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Deferred Tax Assets, Net	$ 184.4		$ 98.2
Effective Income Tax Rate Reconciliation, Percent	35.10%	19.80%

Equity (Details)

Equity (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 925
Common Stock, Dividends, Per Share, Declared	$ 0.01	$ 0.12
Basic EPS
Income available to common shareholders	$ (162,900,000)	$ 163,000,000
Income available to common shareholders, shares	103.7	104
Income available to common shareholders, per share amount	$ (1.57)	$ 1.57
Income allocated to participating securities	$ (100,000)	$ 100,000
Income allocated to participating securities, shares	0	0.1
Net (loss) income	$ (163,000,000)	$ 163,100,000
Diluted potential common shares		1.2
Diluted EPS
Net (loss) income	$ (163,000,000)	$ 163,100,000
Shares	103.7	105.3
Diluted (in dollars per share)	$ (1.57)	$ 1.55
Equity Textuals [Abstract]
Noncontrolling interest	$ 500,000		$ 500,000
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, Current Period, Tax	1,000,000	$ 0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(250,900,000)		(109,200,000)
Pension [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(142,500,000)		(53,100,000)
Accumulated Interest Rate Swaps [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(10,400,000)		(600,000)
SERP and Retiree medical [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	13,000,000		17,100,000
Foreign currency impact on long term intercompany loan [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(16,000,000)		(13,100,000)
Currency translation adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (95,000,000)		$ (59,500,000)

Commitments, Contingencies an_3

Commitments, Contingencies and Guarantees (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Dec. 31, 2019	Mar. 28, 2019	Dec. 31, 2018
Commitments Contingencies And Guarantees [Abstract]
Restricted Cash, Noncurrent	$ 16.5	$ 16.4	$ 16.3	$ 20.2
Service warranty roll forward
Product Warranty And Extraordinary Rework	64.7
Charges to costs and expenses	(1.3)
Product Warranty Accrual, Payments	(0.4)
Product Warranty And Extraordinary Rework	65.2
Product Warranty Extraordinary Rework Accrual Currency Translation Increase Decrease	(0.4)
Commitments Contingencies And Guarantees Textuals [Abstract]
Outstanding amount of guarantees	19	$ 21.5
Product Liability Accrual, Component Amount	8.1
Product Liability Contingency, Loss Exposure in Excess of Accrual, Best Estimate	$ 12.1

Other Income (Expense), Net (De

Other Income (Expense), Net (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Other Income (Loss) [Line Items]
Kansas Development Finance Authority bond	$ 1.1	$ 1.2
Rental and miscellaneous income	0	0.1
Interest Income, Other	6.9	3.2
Foreign currency gains (losses) (1)	5.4	(2)
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	0.1	(15.4)
Gain (Loss) on Sale of Accounts Receivable	(3.1)	(4.6)
Pension Income (Expense) without Service Cost	(59.6)	6.5
VRP pension expense	69.2
Other Noninterest Expense	0.2	0
Total	$ (49)	$ (11)

Segment Information (Details)

Segment Information (Details) $ in Millions	3 Months Ended
	Apr. 02, 2020USD ($)segment	Mar. 28, 2019USD ($)
Segment Reporting Information [Line Items]
Cost of Goods and Services Sold	$ 1,112.5	$ 1,658.3
Segment Revenues
Segment Revenues	1,077.3	1,967.8
Segment Operating Income
Business Segment Operating Income	(76.3)	301.4
Segment Information Unallocated Corporate Selling General And Administrative	(77.4)	(63.6)
Segment Information Unallocated Research And Development	(12.3)	(12.9)
Segment Information Unallocated Cost Of Sales	(1.5)	8.1
Operating (loss) income	$ (167.5)	233
Segment Reporting Information, Additional Information [Abstract]
Number Of Principal Segments | segment	3
Percentage Of Net Revenue Derived From Two Largest Customers	89.00%
Fuselage Systems [Member]
Segment Revenues
Segment Revenues	$ 551.5	1,069.6
Segment Operating Income
Business Segment Operating Income	(86.4)	138.9
Propulsion Systems [Member]
Segment Revenues
Segment Revenues	225.2	485.7
Segment Operating Income
Business Segment Operating Income	(5.3)	95.5
Wing Systems [Member]
Segment Revenues
Segment Revenues	291.4	407.9
Segment Operating Income
Business Segment Operating Income	13.6	65.8
Other Systems [Member]
Segment Revenues
Segment Revenues	9.2	4.6
Segment Operating Income
Business Segment Operating Income	$ 1.8	$ 1.2

Restructuring Charges (Details)

Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 42.6	$ 0
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	31.5
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	11.1
Payments for Restructuring	1.2
Restructuring Costs	9.9
Fuselage Systems [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	30.1
Propulsion Systems [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	8.8
Wing Systems [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 3.7

Acquisition (Details)

Acquisition (Details) - USD ($)	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019
Business Acquisition [Line Items]
Revenues	$ 1,077,300,000	$ 1,967,800,000
Net Income (Loss) Attributable to Parent	$ (163,000,000)	$ 163,100,000
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Goodwill	$ 78,500,000		$ 2,400,000
Weighted Average Amortization Period Intangible Assets	P14Y9M18D
Earnings Per Share, Diluted	$ (1.57)	$ 1.55
FMI [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Net Income (Loss)	$ (162,900,000)	$ 163,000,000
Business Acquisition, Pro Forma Revenue	1,078,100,000	$ 1,975,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	3,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	$ 5,300,000
Business Acquisition, Effective Date of Acquisition	Jan. 10, 2020
Business Acquisition, Name of Acquired Entity	Fiber Materials Inc. (FMI)
Business Combination, Consideration Transferred	$ 121,600,000
Business Combination, Reason for Business Combination	Acquiring FMI aligns with the Company's strategic growth objectives to diversify its customer base and expand the current defense business.
Business Acquisition, Description of Acquired Entity	Founded in 1969 and headquartered in Biddeford, ME, FMI is an industry-leader in the design and manufacture of complex composite solutions that are primarily used in aerospace applications. Over the past 50 years, FMI has developed a portfolio related to its high temperature composites. FMI's main operations focus on multidirectional reinforced composites that enable high-temperature applications such as thermal protection systems, re-entry vehicle nose tips, and rocket motor throats and nozzles. Their unique capabilities have positioned them as a leader in 3D woven carbon-carbon high-temperature materials for hypersonic missiles, which the Department of Defense has identified as a national priority.
cumulative transaction costs	$ 1,500,000
Business Acquisition, Transaction Costs	500,000
Goodwill	76,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	5,300,000
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	10,700,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	1,900,000
business combination, recognized identifiable assets liabilities assumed, contract assets	5,600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	12,300,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	30,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	135,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable	1,800,000
business combination, recognized identifiable assets acquired and liabilities assumed, income tax payable	1,400,000
business combination, recognized identifiable assets acquired and liabilities assumed, contract liabilities	2,200,000
business combination, recognized identifiable assets acquired and liabilities assumed, accrued payroll and benefits	600,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	7,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other	200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	13,900,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	$ 121,600,000
Business Acquisition, Pro Forma Earnings Per Share, Diluted	$ (1.57)	$ 1.55
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual	$ 1,200,000
Asco [Member]
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs	11,000,000	$ 2,800,000
Bombardier [Member]
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs	1,000,000
Technology-Based Intangible Assets [Member] | FMI [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 30,000,000
Weighted Average Amortization Period Intangible Assets	15
Fuselage Systems [Member]
Business Acquisition [Line Items]
Revenues	$ 551,500,000	1,069,600,000
Fuselage Systems [Member] | FMI [Member]
Business Acquisition [Line Items]
Goodwill	43,000,000
Propulsion Systems [Member]
Business Acquisition [Line Items]
Revenues	225,200,000	$ 485,700,000
Propulsion Systems [Member] | FMI [Member]
Business Acquisition [Line Items]
Goodwill	$ 33,200,000

Condensed Consolidating Finan_3

Condensed Consolidating Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2020	Mar. 28, 2019	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 1,077.3	$ 1,967.8
Operating costs and expenses
Cost of sales	1,112.5	1,658.3
Selling, general and administrative	77.4	63.6
Restructuring Charges	42.6	0
Research and development	12.3	12.9
Total operating costs and expenses	1,244.8	1,734.8
Operating income	(167.5)	233
Interest expense and financing fee amortization	(32.2)	(18.8)
Other expense, net	(49)	(11)
Income (loss) before income taxes and equity in net loss of affiliates and subsidiaries	(248.7)	203.2
Income tax benefit (provision)	87.2	(40.1)
Income (loss) Before Equity In Net Income (Loss) Of Affiliates and Subsidiaries	(161.5)	163.1
Equity in net loss of affiliate	(1.5)	0
Equity in net income of subsidiaries	0	0
Net (loss) income	(163)	163.1
Total other comprehensive income (loss)	(141.7)	10
Comprehensive Income, Net of Tax, Attributable to Parent	(304.7)	173.1
Assets
Cash and cash equivalents	1,850.4	1,245	$ 2,367.2	$ 794.1
Restricted Cash and Cash Equivalents	0.3		0.3
Accounts receivable, net	508.6		546.4
Unbilled Receivables, Current	380.9		528.3
Inventory	1,168.7		1,118.8
Other current assets	134		98.7
Total current assets	4,026.1		4,643
Property, plant and equipment, net	2,253.2		2,271.7
Operating Lease, Right-of-Use Asset	47.5		48.9
Unbilled Receivable, Non Current	10.4		6.4
Pension assets	282.6		449.1
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	192.6		106.5
Goodwill	78.5		2.4
Intangible Assets, Net (Excluding Goodwill)	30.6		1.2
Deferred income taxes	79.6		76.8
Other assets	7,001.1		7,606
Total assets
Liabilities	740.7		1,058.3
Accounts payable	286.1		240.2
Accrued expenses	17.6		84.5
Profit sharing	52.7		50.2
Operating Lease, Liability, Current	5.9		6
Operating lease liabilities, short-term	17.8		21.6
Billings in Excess of Cost, Noncurrent	388.9		356.3
Billings in Excess of Cost, Current	166.9		158.3
Provision for Loss on Contracts	91.5		83.9
Forward loss provision, short-term	17.9		14.8
Deferred grant income liability — current	37		42.9
Other current liabilities	1,434.1		1,760.7
Long-term debt	2,978.2		2,984.1
Operating Lease, Liability, Noncurrent	41.7		43
Advance payments, long-term	327.3		333.3
Pension/OPEB obligation	50.9		35.7
Provision for Loss on Contacts, Non Current	146.9		163.5
Deferred grant income liability — non-current	27.4		29
Deferred revenue and other deferred credits	36.8		34.4
Deferred Tax Liabilities, Net, Noncurrent	8.2		8.3
Deferred income taxes	104.3		95.8
Total equity	1,456.4		1,761.9
Total liabilities and equity	7,001.1		7,606
Operating activities
Net cash (used in) operating activities	(331.3)	242.2
Investing activities
Purchase of property, plant and equipment	(31)	(40.8)
Payments for (Proceeds from) Other Investing Activities	0.3	0.1
Payments to Acquire Businesses, Net of Cash Acquired	(118.1)	0
Payments for (Proceeds from) Other Investing Activities	(1.8)
Net cash used in investing activities	(147.3)	(40.7)
Proceeds from Issuance of Debt	0
Proceeds from Lines of Credit	0	100
Proceeds from (Payments for) Other Financing Activities	10	0
Proceeds from Issuance of Senior Long-term Debt		(250)
Financing activities
Principal payments of debt	(7.3)	(2.6)
Repayments of Debt	(5.7)	0
Early Repayment of Senior Debt		(2.6)
Collection on (repayment of) intercompany debt		0
Payment, Tax Withholding, Share-based Payment Arrangement	(13.1)	(10)
Proceeds (payments) from subsidiary for purchase of treasury stock		0
Debt issuance and financing costs	4.8	0
Payments for Repurchase of Common Stock	0	(75)
Proceeds from subsidiary (payments to Parent) to pay dividends	0	0
Payments of Dividends	(12.4)	(12.7)
Proceeds from Stock Plans	1.3	0
Net cash (used in) provided by financing activities	(32)	249.7
Effect of exchange rate changes on cash and cash equivalents	(6.2)	(0.3)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(516.8)	450.9
Cash and cash equivalents, beginning of period	2,350.5	773.6
Cash, cash equivalents, and restricted cash, end of period	1,833.6	1,228.4
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	(164)	(170.6)
Operating costs and expenses
Cost of sales	(164)	(170.6)
Restructuring Charges	0
Total operating costs and expenses	(164)	(170.6)
Interest expense and financing fee amortization	0.8	1
Other expense, net	(0.8)	(1)
Equity in net income of subsidiaries	139.5	(194.7)
Net (loss) income	139.5	(194.7)
Total other comprehensive income (loss)	117.2	(20.4)
Comprehensive Income, Net of Tax, Attributable to Parent	256.7	(215.1)
Assets
Restricted Cash and Cash Equivalents	0		0
Accounts receivable, net	(325.3)		(320.2)
Unbilled Receivables, Current	0		0
Inventory			0
Total current assets	(325.3)		(320.2)
Operating Lease, Right-of-Use Asset	0		0
Unbilled Receivable, Non Current	0		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent			0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Investment in subsidiary	(2,277.4)		(2,600.3)
Deferred income taxes	(186.8)		(186.8)
Other assets	(2,789.5)		(3,107.3)
Total assets
Liabilities	(325.3)		(320.2)
Operating Lease, Liability, Current	0		0
Billings in Excess of Cost, Noncurrent	0		0
Billings in Excess of Cost, Current	0		0
Provision for Loss on Contracts	0		0
Other current liabilities	(325.3)		(320.2)
Long-term debt	(86.2)		(86.2)
Operating Lease, Liability, Noncurrent	0		0
Provision for Loss on Contacts, Non Current	0		0
Deferred Tax Liabilities, Net, Noncurrent	0		0
Deferred income taxes	(100.6)		(100.6)
Total equity	(2,277.4)		(2,600.3)
Total liabilities and equity	(2,789.5)		(3,107.3)
Operating activities
Net cash (used in) operating activities
Investing activities
Payments for (Proceeds from) Other Investing Activities		0
Payments to Acquire Businesses, Net of Cash Acquired	0
Payments for (Proceeds from) Other Investing Activities	0
Proceeds from Lines of Credit		0
Proceeds from (Payments for) Other Financing Activities	0
Financing activities
Early Repayment of Senior Debt		0
Collection on (repayment of) intercompany debt		0
Payment, Tax Withholding, Share-based Payment Arrangement	0	0
Proceeds (payments) from subsidiary for purchase of treasury stock		0
Debt issuance and financing costs	0
Payments for Repurchase of Common Stock		0
Proceeds from subsidiary (payments to Parent) to pay dividends	0	0
Payments of Dividends	0	0
Proceeds from Stock Plans	0
Effect of exchange rate changes on cash and cash equivalents
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0
Operating costs and expenses
Selling, general and administrative	3.5	2.3
Restructuring Charges	0
Total operating costs and expenses	3.5	2.3
Operating income	(3.5)	(2.3)
Income (loss) before income taxes and equity in net loss of affiliates and subsidiaries	(3.5)	(2.3)
Income tax benefit (provision)	1.2	0.5
Income (loss) Before Equity In Net Income (Loss) Of Affiliates and Subsidiaries	(2.3)	(1.8)
Equity in net income of subsidiaries	(160.7)	164.9
Net (loss) income	(163)	163.1
Total other comprehensive income (loss)	(141.7)	10
Comprehensive Income, Net of Tax, Attributable to Parent	(304.7)	173.1
Assets
Restricted Cash and Cash Equivalents	0		0
Unbilled Receivables, Current	0		0
Inventory			0
Operating Lease, Right-of-Use Asset	0		0
Unbilled Receivable, Non Current	0		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent			0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Investment in subsidiary	1,456.4		1,761.9
Other assets	1,456.4		1,761.9
Total assets
Operating Lease, Liability, Current			0
Billings in Excess of Cost, Noncurrent	0		0
Billings in Excess of Cost, Current	0
Provision for Loss on Contracts	0		0
Operating Lease, Liability, Noncurrent			0
Provision for Loss on Contacts, Non Current	0		0
Deferred Tax Liabilities, Net, Noncurrent	0		0
Total equity	1,456.4		1,761.9
Total liabilities and equity	1,456.4		1,761.9
Investing activities
Payments for (Proceeds from) Other Investing Activities		0
Payments to Acquire Businesses, Net of Cash Acquired	0
Payments for (Proceeds from) Other Investing Activities	0
Proceeds from (Payments for) Other Financing Activities	0
Financing activities
Early Repayment of Senior Debt		0
Collection on (repayment of) intercompany debt		0
Payment, Tax Withholding, Share-based Payment Arrangement	0	0
Proceeds (payments) from subsidiary for purchase of treasury stock		(75)
Debt issuance and financing costs	0
Payments for Repurchase of Common Stock		75
Proceeds from subsidiary (payments to Parent) to pay dividends	12.4	12.7
Payments of Dividends	(12.4)	(12.7)
Proceeds from Stock Plans	0
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	230.9	256.8
Operating costs and expenses
Cost of sales	206.4	215.9
Selling, general and administrative	5	4
Restructuring Charges	0
Research and development	0.6	1.1
Total operating costs and expenses	212	221
Operating income	18.9	35.8
Interest expense and financing fee amortization	(0.9)	(1)
Other expense, net	6.1	(1.6)
Income (loss) before income taxes and equity in net loss of affiliates and subsidiaries	24.1	33.2
Income tax benefit (provision)	(3.6)	(5.3)
Income (loss) Before Equity In Net Income (Loss) Of Affiliates and Subsidiaries	20.5	27.9
Equity in net loss of affiliate	(1.5)
Net (loss) income	19	27.9
Total other comprehensive income (loss)	24.5	10.4
Comprehensive Income, Net of Tax, Attributable to Parent	43.5	38.3
Assets
Cash and cash equivalents	116.7	67.4	157.2	68.6
Restricted Cash and Cash Equivalents	0		0
Accounts receivable, net	301.2		250.7
Unbilled Receivables, Current	52.7		69.5
Inventory	190.9		195.2
Other current assets	4.3		5.2
Total current assets	665.7		677.8
Property, plant and equipment, net	183.6		192.4
Operating Lease, Right-of-Use Asset	0.2		0.2
Unbilled Receivable, Non Current	6.8		0
Pension assets	23.6		24.9
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	0.2		0.2
Goodwill	2.3		2.4
Intangible Assets, Net (Excluding Goodwill)	0		0
Deferred income taxes	113.7		116
Other assets	996.1		1,013.9
Total assets
Liabilities	180		175.1
Accounts payable	34		29.4
Accrued expenses	2.2		7.6
Profit sharing	1.7		1.6
Operating Lease, Liability, Current	0		0.1
Billings in Excess of Cost, Noncurrent	0		0
Billings in Excess of Cost, Current	0		0
Provision for Loss on Contracts	0		0
Forward loss provision, short-term	0.3		0.3
Deferred grant income liability — current	9.8		11.5
Other current liabilities	228		225.6
Long-term debt	94.7		94.7
Operating Lease, Liability, Noncurrent	0.1		0.1
Provision for Loss on Contacts, Non Current	0		0
Deferred grant income liability — non-current	18.3		19.8
Deferred revenue and other deferred credits	5.4		4
Deferred Tax Liabilities, Net, Noncurrent	8.2		8.3
Deferred income taxes	5.9		6.3
Total equity	635.5		655.1
Total liabilities and equity	996.1		1,013.9
Operating activities
Net cash (used in) operating activities	(28.6)	41.5
Investing activities
Purchase of property, plant and equipment	(7.2)	(8.2)
Payments for (Proceeds from) Other Investing Activities		0
Payments to Acquire Businesses, Net of Cash Acquired	0
Payments for (Proceeds from) Other Investing Activities	(1.5)
Net cash used in investing activities	(5.7)	(8.2)
Proceeds from Lines of Credit		0
Proceeds from (Payments for) Other Financing Activities	0
Financing activities
Principal payments of debt	(0.3)
Early Repayment of Senior Debt		0.2
Collection on (repayment of) intercompany debt	0.3	34
Payment, Tax Withholding, Share-based Payment Arrangement	0	0
Proceeds (payments) from subsidiary for purchase of treasury stock		0
Debt issuance and financing costs	0
Payments for Repurchase of Common Stock		0
Proceeds from subsidiary (payments to Parent) to pay dividends	0	0
Payments of Dividends	0	0
Proceeds from Stock Plans	0
Net cash (used in) provided by financing activities		(34.2)
Effect of exchange rate changes on cash and cash equivalents	(6.2)	(0.3)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(40.5)	(1.2)
Cash and cash equivalents, beginning of period	157.2
Cash, cash equivalents, and restricted cash, end of period	116.6
Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	899.2	1,765.2
Operating costs and expenses
Cost of sales	962.7	1,500.3
Selling, general and administrative	68.1	56.5
Restructuring Charges	42.6
Research and development	11.6	11.4
Total operating costs and expenses	1,085	1,568.2
Operating income	(185.8)	197
Interest expense and financing fee amortization	(32.1)	(18.8)
Other expense, net	(54.3)	(8.4)
Income (loss) before income taxes and equity in net loss of affiliates and subsidiaries	(272.2)	169.8
Income tax benefit (provision)	90.3	(34.7)
Income (loss) Before Equity In Net Income (Loss) Of Affiliates and Subsidiaries	(181.9)	135.1
Equity in net income of subsidiaries	21.2	29.8
Net (loss) income	(160.7)	164.9
Total other comprehensive income (loss)	(141.7)	10
Comprehensive Income, Net of Tax, Attributable to Parent	(302.4)	174.9
Assets
Cash and cash equivalents	1,733.7	1,177.6	2,210	$ 725.5
Restricted Cash and Cash Equivalents	0.3		0.3
Accounts receivable, net	480.1		565.4
Unbilled Receivables, Current	328.2		458.8
Inventory	832.8		786.8
Other current assets	129.7		93.5
Total current assets	3,488.1		4,098.1
Property, plant and equipment, net	1,773.9		1,773
Operating Lease, Right-of-Use Asset	40		41.2
Unbilled Receivable, Non Current	3.6		6.4
Pension assets	259		424.2
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	192.4		106.3
Goodwill	76.2		0
Intangible Assets, Net (Excluding Goodwill)	30.6		1.2
Investment in subsidiary	821		838.4
Deferred income taxes	152.7		147.6
Other assets	6,837.5		7,436.4
Total assets
Liabilities	660.4		977.1
Accounts payable	251		210
Accrued expenses	15.4		76.9
Profit sharing	50.8		48.4
Operating Lease, Liability, Current	5.3		5.3
Operating lease liabilities, short-term	17.8		21.6
Billings in Excess of Cost, Noncurrent	388.9		356.3
Billings in Excess of Cost, Current	166.9		158.3
Provision for Loss on Contracts	91.5		83.9
Forward loss provision, short-term	17.6		14.5
Deferred grant income liability — current	27.2		29.3
Other current liabilities	1,303.9		1,625.3
Long-term debt	2,968.9		2,974.7
Operating Lease, Liability, Noncurrent	34.9		36
Advance payments, long-term	327.3		333.3
Pension/OPEB obligation	50.9		35.7
Provision for Loss on Contacts, Non Current	146.9		163.5
Deferred grant income liability — non-current	9.1		9.2
Deferred revenue and other deferred credits	31.4		30.4
Deferred Tax Liabilities, Net, Noncurrent	0		0
Deferred income taxes	199		190.1
Total equity	1,376.3		1,681.9
Total liabilities and equity	6,837.5		7,436.4
Operating activities
Net cash (used in) operating activities	(312.5)	197.4
Investing activities
Purchase of property, plant and equipment	(23.4)	(29.3)
Payments for (Proceeds from) Other Investing Activities		0.1
Payments to Acquire Businesses, Net of Cash Acquired	(118.1)
Payments for (Proceeds from) Other Investing Activities	0.3
Net cash used in investing activities	(141.2)	(29.2)
Proceeds from Lines of Credit		100
Proceeds from (Payments for) Other Financing Activities	10
Proceeds from Issuance of Senior Long-term Debt		250
Financing activities
Principal payments of debt	(7)
Repayments of Debt	(5.7)
Early Repayment of Senior Debt		(2.4)
Collection on (repayment of) intercompany debt	9.1	34
Payment, Tax Withholding, Share-based Payment Arrangement	(13.1)	(10)
Proceeds (payments) from subsidiary for purchase of treasury stock		75
Debt issuance and financing costs	(4.8)
Payments for Repurchase of Common Stock		0
Proceeds from subsidiary (payments to Parent) to pay dividends	(12.4)	(12.7)
Payments of Dividends	0	0
Proceeds from Stock Plans	(1.3)
Net cash (used in) provided by financing activities	(22.6)	283.9
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(476.3)	452.1
Cash and cash equivalents, beginning of period	2,193.3
Cash, cash equivalents, and restricted cash, end of period	1,717
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	111.2	116.4
Operating costs and expenses
Cost of sales	107.4	112.7
Selling, general and administrative	0.8	0.8
Restructuring Charges	0
Research and development	0.1	0.4
Total operating costs and expenses	108.3	113.9
Operating income	2.9	2.5
Interest expense and financing fee amortization	0
Other expense, net	0
Income (loss) before income taxes and equity in net loss of affiliates and subsidiaries	2.9	2.5
Income tax benefit (provision)	0.7	(0.6)
Income (loss) Before Equity In Net Income (Loss) Of Affiliates and Subsidiaries	2.2	1.9
Equity in net loss of affiliate	0
Equity in net income of subsidiaries	0
Net (loss) income	2.2	1.9
Total other comprehensive income (loss)	0
Comprehensive Income, Net of Tax, Attributable to Parent	2.2	1.9
Assets
Restricted Cash and Cash Equivalents	0		0
Accounts receivable, net	52.6		50.5
Unbilled Receivables, Current	0		0
Inventory	145		136.8
Other current assets	0
Total current assets	197.6		187.3
Property, plant and equipment, net	295.7		306.3
Operating Lease, Right-of-Use Asset	7.3		7.5
Unbilled Receivable, Non Current	0		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent			0
Goodwill	0		0
Intangible Assets, Net (Excluding Goodwill)	0		0
Other assets	500.6		501.1
Total assets
Liabilities	225.6		226.3
Accounts payable	1.1		0.8
Profit sharing	0.2		0.2
Operating Lease, Liability, Current	0.6		0.6
Billings in Excess of Cost, Noncurrent	0		0
Billings in Excess of Cost, Current	0
Provision for Loss on Contracts	0		0
Deferred grant income liability — current			2.1
Other current liabilities	227.5		230
Long-term debt	0.8		0.9
Operating Lease, Liability, Noncurrent	6.7		6.9
Provision for Loss on Contacts, Non Current	0		0
Deferred Tax Liabilities, Net, Noncurrent	0		0
Total equity	265.6		263.3
Total liabilities and equity	500.6		$ 501.1
Operating activities
Net cash (used in) operating activities	9.8	3.3
Investing activities
Purchase of property, plant and equipment	(0.4)	(3.3)
Payments for (Proceeds from) Other Investing Activities		0
Payments to Acquire Businesses, Net of Cash Acquired	0
Net cash used in investing activities	(0.4)	(3.3)
Proceeds from Lines of Credit		0
Proceeds from (Payments for) Other Financing Activities	0
Financing activities
Repayments of Debt	0
Early Repayment of Senior Debt		0
Collection on (repayment of) intercompany debt	(9.4)	0
Payment, Tax Withholding, Share-based Payment Arrangement	0	0
Proceeds (payments) from subsidiary for purchase of treasury stock		0
Debt issuance and financing costs	0
Payments for Repurchase of Common Stock		0
Proceeds from subsidiary (payments to Parent) to pay dividends	0	0
Payments of Dividends	0	$ 0
Proceeds from Stock Plans	0
Net cash (used in) provided by financing activities	(9.4)
Cash, cash equivalents, and restricted cash, end of period	$ 0

Uncategorized Items - spr202004

Label	Element	Value
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock	In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-13, which requires the immediate recognition of management's estimates of current expected credit losses. ASU 2016-13 is effective for fiscal years and interim reporting periods within those years beginning after December 15, 2019. Early adoption is permitted after fiscal years beginning December 15, 2018. The Company adopted ASU 2016-13 as of January 1, 2020 by means of the modified retrospective method and required cumulative-effect adjustment to the opening retained earnings as of that date. The cumulative-effect adjustment to the opening retained earnings as of January 1, 2020 was not material. All credit losses in accordance with ASU 2016-13 were on receivables and/or contract assets arising from the Company’s contracts with customers including the cumulative-effect adjustment to the opening retained earnings. There is no significant impact to our operating results for the current period due to ASU 2016-13. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement (“ASU 2018-13”), which modifies the disclosure requirements on fair value measurements by removing, modifying, or adding certain disclosures. Certain disclosures in ASU 2018-13 are required to be applied on a retrospective basis and others on a prospective basis. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. There was not a significant impact of adopting this guidance on our consolidated financial statements. In January 2017, the FASB issued Accounting Standards Update No. 2017-04, Intangibles-Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment (“ASU 2017-04”), which eliminates Step 2 of the goodwill impairment test and the qualitative assessment for any reporting unit with a zero or negative carrying amount. Under ASU 2017-04, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. ASU 2017-04 is effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. The adoption did not have an impact on our financial statements.
Treasury Stock, Common [Member]
Treasury Stock, Value	us-gaap_TreasuryStockValue	$ (2,456,000,000)
Treasury Stock, Value, Acquired, Cost Method	us-gaap_TreasuryStockValueAcquiredCostMethod	(75,000,000)
Stockholders' Equity, Total [Member]
Net Income (Loss) Attributable to Parent	us-gaap_NetIncomeLoss	163,100,000
Impact on Retained Earnings, Adoption of ASC 606	spr_ImpactonRetainedEarningsAdoptionofASC606	0
Other Comprehensive Income (Loss), Net of Tax	us-gaap_OtherComprehensiveIncomeLossNetOfTax	10,000,000
Treasury Stock, Value, Acquired, Cost Method	us-gaap_TreasuryStockValueAcquiredCostMethod	(75,100,000)
Stockholders' Equity Attributable to Parent	us-gaap_StockholdersEquity	1,320,600,000
Stock Issued During Period, Value, Restricted Stock Award, Gross	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross	7,700,000
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	12,700,000
Payment, Tax Withholding, Share-based Payment Arrangement	us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation	(10,000,000)
Additional Paid-in Capital [Member]
Stock Issued During Period, Value, Restricted Stock Award, Gross	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross	7,700,000
Additional Paid in Capital, Common Stock	us-gaap_AdditionalPaidInCapitalCommonStock	1,098,600,000
Payment, Tax Withholding, Share-based Payment Arrangement	us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation	(10,000,000)
Retained Earnings [Member]
Net Income (Loss) Attributable to Parent	us-gaap_NetIncomeLoss	163,100,000
Impact on Retained Earnings, Adoption of ASC 606	spr_ImpactonRetainedEarningsAdoptionofASC606	8,300,000
Retained Earnings (Accumulated Deficit)	us-gaap_RetainedEarningsAccumulatedDeficit	2,871,900,000
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	12,700,000
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Other Comprehensive Income (Loss), Net of Tax	us-gaap_OtherComprehensiveIncomeLossNetOfTax	10,000,000
Accumulated Other Comprehensive Income (Loss), Net of Tax	us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax	(194,900,000)
Common Stock [Member]
Common Stock, Value, Outstanding	us-gaap_CommonStockValueOutstanding	$ 1,000,000
Treasury Stock, Shares, Acquired	us-gaap_TreasuryStockSharesAcquired	796,409
Treasury Stock, Value, Acquired, Cost Method	us-gaap_TreasuryStockValueAcquiredCostMethod	$ (100,000)
Common Stock, Shares, Outstanding	us-gaap_CommonStockSharesOutstanding	104,876,827
Shares Issued, Shares, Share-based Payment Arrangement, Forfeited	us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationForfeited	(27,604)
Shares Granted, Value, Share-based Payment Arrangement, Forfeited	us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited	$ 0
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture	us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross	$ 0
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation	(112,436)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	351,459