Segment Reporting - Reconciliation of Consolidated Segment Earnings to Consolidated Income Before Provision for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 29, 2025	Mar. 30, 2024
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	$ 5,560.3	$ 5,994.6
Cost of sales	5,201.1	5,596.5
Gross margin	359.2	398.1
Selling, general and administrative	172.4	186.5
Amortization of intangibles	5.2	15.1
Intersegment support activities	0.0	0.0
Segment earnings	181.6	196.5
Interest expense, net	25.8	26.1
Other expense, net	20.4	13.5
Consolidated income before provision for income taxes and equity in net income of affiliates	135.4	156.9
Seating
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	4,151.1	4,477.6
E-Systems
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	1,409.2	1,517.0
Operating segments \| Seating
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	4,151.1	4,477.6
Cost of sales	3,845.9	4,138.5
Gross margin	306.4	339.8
Selling, general and administrative	85.5	87.0
Amortization of intangibles	3.4	9.8
Intersegment support activities	1.8	1.4
Segment earnings	215.7	241.6
Operating segments \| E-Systems
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	1,409.2	1,517.0
Cost of sales	1,377.4	1,471.0
Gross margin	95.2	103.6
Selling, general and administrative	35.5	42.0
Amortization of intangibles	1.8	5.3
Intersegment support activities	2.4	2.2
Segment earnings	55.5	54.1
Intersegment Eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	(64.6)	(58.3)
Intersegment Eliminations \| Seating
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	1.2	0.7
Intersegment Eliminations \| E-Systems
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	63.4	57.6
Other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated
Revenue	0.0	0.0
Cost of sales	(22.2)	(13.0)
Gross margin	(42.4)	(45.3)
Selling, general and administrative	51.4	57.5
Amortization of intangibles	0.0	0.0
Intersegment support activities	(4.2)	(3.6)
Segment earnings	$ (89.6)	$ (99.2)

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