Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jul. 02, 2016	Jun. 27, 2015	Jul. 02, 2016	Jun. 27, 2015
Income Tax Contingency [Line Items]
Provision for income taxes	$ 101.0	$ 71.9	$ 199.2	$ 134.8
Pretax income before equity in net income of affiliates	$ 376.0	$ 256.3	$ 719.9	$ 462.6
Effective tax rate	26.90%	28.10%	27.70%	29.10%
Tax benefits			$ 12.1	$ 29.8
U.S. federal statutory income tax rate			35.00%	35.00%
Beijing BAI Lear Automotive Systems Co., Ltd.
Income Tax Contingency [Line Items]
Gain on consolidation of affiliate	$ 30.3		$ 30.3

Income Tax Expense (Benefit), Discrete Items

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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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