Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 830.7	$ 1,246.7	$ 1,380.9
Other comprehensive income (loss), net of tax:
Defined benefit plan adjustments	(44.8)	11.2	8.8
Derivative instruments and hedging activities	19.5	13.2
Derivative instruments and hedging activities			22.2
Foreign currency translation adjustments	(45.1)	(233.0)	305.0
Total other comprehensive income (loss)	(70.4)	(208.6)	336.0
Consolidated comprehensive income	760.3	1,038.1	1,716.9
Less: Comprehensive income attributable to noncontrolling interests	73.6	80.7	81.3
Comprehensive income attributable to Lear	$ 686.7	$ 957.4	$ 1,635.6

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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