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.

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

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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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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.

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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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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Long-Term Assets - Investment in Affiliates Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 31, 2018	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Annual sales		$ 5,580.8	$ 5,123.2	$ 11,314.5	$ 10,121.7
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