Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(12))
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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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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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Segment Reporting - Summary of Segment Financial Information (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Revenues from external customers	$ 5,363.8	$ 4,981.5	$ 5,123.2	$ 4,998.5	$ 4,643.5	$ 4,526.4	$ 4,724.8	$ 4,662.9	$ 20,467.0	$ 18,557.6	$ 18,211.4
Segment earnings									1,608.3	1,427.2	1,186.8
Depreciation and amortization									427.7	378.2	347.8
Capital expenditures									594.5	528.3	485.8
Total assets	11,945.9				9,900.6				11,945.9	9,900.6
Operating segments
Segment Reporting Information [Line Items]
Segment earnings									1,892.4	1,727.3	1,461.4
Operating segments \| Seating
Segment Reporting Information [Line Items]
Revenues from external customers									15,873.0	14,356.7	14,098.5
Segment earnings									1,250.8	1,136.0	907.0
Depreciation and amortization									289.5	258.1	239.3
Capital expenditures									398.3	341.6	317.2
Total assets	7,303.4				6,199.2				7,303.4	6,199.2
Operating segments \| E-Systems
Segment Reporting Information [Line Items]
Revenues from external customers									4,594.0	4,200.9	4,112.9
Segment earnings									641.6	591.3	554.4
Depreciation and amortization									123.4	107.6	99.3
Capital expenditures									176.3	162.4	134.4
Total assets	2,268.0				1,675.9				2,268.0	1,675.9
Other
Segment Reporting Information [Line Items]
Revenues from external customers									0.0	0.0	0.0
Segment earnings									(284.1)	(300.1)	(274.6)
Depreciation and amortization									14.8	12.5	9.2
Capital expenditures									19.9	24.3	$ 34.2
Total assets	$ 2,374.5				$ 2,025.5				$ 2,374.5	$ 2,025.5