Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 1,040.5	$ 795.8	$ 702.3
Other comprehensive income (loss), net of tax:
Defined benefit plan adjustments	1.8	24.6	(114.7)
Derivative instruments and hedging activities	(6.4)	(5.5)	(27.9)
Foreign currency translation adjustments	(109.5)	(251.1)	(195.2)
Total other comprehensive loss	(114.1)	(232.0)	(337.8)
Consolidated comprehensive income	926.4	563.8	364.5
Less: Comprehensive income attributable to noncontrolling interests	56.8	46.4	28.0
Comprehensive income attributable to Lear	$ 869.6	$ 517.4	$ 336.5

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

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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