Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

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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-Publisher FASB
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-SubTopic 10
-Section 50
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
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Long-Term Assets - Investment in Affiliates Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2018	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Annual sales		$ 5,733.7	$ 4,998.5
Lear FAWSN
Business Acquisition [Line Items]
Percentage of voting interests acquired	20.00%
Fair value of previously held equity interest		23.0
Lear FAWSN \| Customer relationships
Business Acquisition [Line Items]
Acquired intangible assets, weighted average useful life	10 years
Other Income And Expense \| Lear FAWSN
Business Acquisition [Line Items]
Consolidation of affiliate, revaluation gain		$ 10.0
Lear FAWSN
Business Acquisition [Line Items]
Fair value of previously held equity interest	$ 23.0
Fair value of the noncontrolling interest	$ 14.0
Annual sales				$ 100.0