Commitments, Contingencies and Guarantees (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 27, 2012	Dec. 31, 2013 employee	Dec. 31, 2012
Contingencies [Line Items]
Valuation allowance		$ (396.5)	$ (10.4)
Valuation Allowance, Deferred Tax Asset, Change in Amount		5.1
Loss Contingency Accrual		1.0	0
Current and former Spirit Employees, putative		2,500
Vesting years, putative		10 years
Service warranty roll forward
Product Warranty And Extraordinary Rework, Beginning Balance		30.9	19.6
Charges to costs and expenses		38.3	12.0
Write-offs, net of recoveries		(0.6)	(0.9)
Exchange rate		0.1	0.2
Product Warranty And Extraordinary Rework, Ending Balance		68.7	30.9
Commitments Contingencies And Guarantees Textuals [Abstract]
Net Forward Loss Charge Recorded	590.0	1,133.3
Capital Commitments		226.0	264.8
Interest Expense Related To Capital Leases		0.9	1.2
Outstanding Amount Of Letter Of Credit		19.9
Outstanding Amount Of Guarantees		24.8	25.6
Industrial Revenue Bond [Member]
Commitments Contingencies And Guarantees Textuals [Abstract]
Tax Exempt Bonds		394.7	345.7
KFDA [Member]
Commitments Contingencies And Guarantees Textuals [Abstract]
Tax Exempt Bonds		80.0
Allowance For Warranties And Extraordinary Rework [Member]
Service warranty roll forward
Product Warranty And Extraordinary Rework, Ending Balance		$ 68.7