Segment Information (PPY Table) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Revenues	$ 6,316.6	$ 6,047.9	$ 5,029.6
Cost of Sales	(7,492.5)	(5,657.6)	(4,814.9)
Excess Capacity Costs- B737MAX and A320 Production Schedules	(196.5)	(184.1)	(157.3)
Segment Reporting, Other Segment Item, Amount			(8.8)
Gross Operating Income	(1,372.4)	206.2	48.6
Restructuring Charges	(0.7)	(7.2)	(0.2)
Consolidated Business Segments Operating Income	(1,373.1)	193.1	48.4
Segment Reporting, Unallocated Selling, General and Administrative Expense	(365.5)
Selling, General and Administrative Expense	(365.5)	(281.9)	(279.2)
Segment Information Unallocated Research And Development	(47.5)
Research and Development Expense	(47.5)	(45.4)	(50.4)
Operating loss	(1,786.1)	(134.2)	(281.2)
Interest and Debt Expense	(353.5)	(318.7)	(244.1)
Other Operating Income (Expense), Net	(2.0)	(140.4)	(14.1)
Loss before income taxes and equity in net income (loss) of affiliates	(2,141.6)	(593.3)	(539.4)
Commercial [Member]
Segment Reporting Information [Line Items]
Revenues	4,927.4	4,885.0	4,068.4
Cost of Sales	(6,263.3)	(4,627.3)	(3,993.0)
Excess Capacity Costs- B737MAX and A320 Production Schedules	(186.5)	(177.3)	(149.5)
Segment Reporting, Other Segment Item, Amount			(8.6)
Segment Gross Income	(1,522.4)	80.4	(82.7)
Restructuring Charges	0.7	6.3	0.2
Business Segment Operating Income	(1,523.1)	66.0	(82.9)
Operating loss	(1,523.1)	66.0	(82.9)
Loss before income taxes and equity in net income (loss) of affiliates	(1,523.1)	66.0	(82.9)
Defense & Space [Member]
Segment Reporting Information [Line Items]
Revenues	975.2	789.0	649.8
Cost of Sales	(870.5)	(736.4)	(571.5)
Excess Capacity Costs- B737MAX and A320 Production Schedules	(10.0)	(6.8)	(7.8)
Segment Reporting, Other Segment Item, Amount			2.3
Segment Gross Income	94.7	45.8	72.8
Restructuring Charges	0.0	0.9	0.0
Business Segment Operating Income	94.7	44.7	72.8
Operating loss	94.7	44.7	72.8
Loss before income taxes and equity in net income (loss) of affiliates	94.7	44.7	72.8
Aftermarket [Member]
Segment Reporting Information [Line Items]
Revenues	414.0	373.9	311.4
Cost of Sales	(358.7)	(293.9)	(250.4)
Excess Capacity Costs- B737MAX and A320 Production Schedules	0.0	0.0	0.0
Segment Reporting, Other Segment Item, Amount			(2.5)
Segment Gross Income	55.3	80.0	58.5
Restructuring Charges	0.0	0.0	0.0
Business Segment Operating Income	55.3	82.4	58.5
Operating loss	55.3	82.4	58.5
Loss before income taxes and equity in net income (loss) of affiliates	55.3	82.4	58.5
unallocated
Segment Reporting Information [Line Items]
Segment Reporting, Unallocated Selling, General and Administrative Expense		(281.9)	(279.2)
Segment Information Unallocated Research And Development		(45.4)	(50.4)
Operating loss	(413.0)	(327.3)	(329.6)
Interest and Debt Expense	(353.5)	(318.7)	(244.1)
Other Operating Income (Expense), Net	(2.0)	(140.4)	(14.1)
Loss before income taxes and equity in net income (loss) of affiliates	$ (768.5)	$ (786.4)	$ (587.8)