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Segment Reporting - Summary of Segment Financial Information (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 31, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenues from external customers	$ 4,817.6	$ 4,825.0	$ 5,007.6	$ 5,160.1	$ 4,942.4	$ 4,891.6	$ 5,580.8	$ 5,733.7	$ 19,810.3	$ 21,148.5	$ 20,467.0
Segment earnings									1,070.2	1,654.1	1,608.3
Depreciation and amortization									509.9	484.4	427.7
Capital expenditures									603.9	677.0	594.5
Total assets	12,680.7				11,600.7				12,680.7	11,600.7
Operating segments
Segment Reporting Information [Line Items]
Segment earnings									1,327.5	1,892.1	1,892.4
Operating segments \| Seating
Segment Reporting Information [Line Items]
Revenues from external customers									15,097.2	16,021.9	15,873.0
Segment earnings									961.2	1,263.6	1,250.8
Depreciation and amortization									331.0	323.5	289.5
Capital expenditures									370.4	459.8	398.3
Total assets	7,277.6				6,857.5				7,277.6	6,857.5
Operating segments \| E-Systems
Segment Reporting Information [Line Items]
Revenues from external customers									4,713.1	5,126.6	4,594.0
Segment earnings									366.3	628.5	641.6
Depreciation and amortization									163.0	146.2	123.4
Capital expenditures									213.9	208.4	176.3
Total assets	3,068.1				2,452.0				3,068.1	2,452.0
Other
Segment Reporting Information [Line Items]
Revenues from external customers									0.0	0.0	0.0
Segment earnings									(257.3)	(238.0)	(284.1)
Depreciation and amortization									15.9	14.7	14.8
Capital expenditures									19.6	8.8	$ 19.9
Total assets	$ 2,335.0				$ 2,291.2				$ 2,335.0	$ 2,291.2