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Long-Lived Assets - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Sep. 06, 2021	Oct. 02, 2021	Oct. 03, 2020	Oct. 02, 2021	Oct. 03, 2020
Property, Plant and Equipment [Line Items]
Depreciation expense		$ 124.6	$ 120.0	$ 374.0	$ 347.7
Asset impairment charges				2.0	3.4
Amortization of intangible assets		$ 15.8	$ 16.3	57.4	49.4
Impairment loss				1.0
Affiliated Entity
Property, Plant and Equipment [Line Items]
Impairment loss				1.0
Shenyang Jinbei Lear Auto Parts Co., Ltd
Property, Plant and Equipment [Line Items]
Equity method investment, ownership percentage	49.00%
Payments to acquire equity method investments	$ 41.3
E-Systems
Property, Plant and Equipment [Line Items]
Asset impairment charges				8.5
Restructuring Charges
Property, Plant and Equipment [Line Items]
Asset impairment charges				$ 1.0	$ 12.5