Financial Instruments - Additional Information (Detail) - USD ($)	6 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Financial Instruments [Line Items]
Gain (loss) expected to be reclassified into earnings from accumulated other comprehensive loss	$ (4,500,000)
Derivative contracts classified within Level 3 of fair value hierarchy	0	$ 0
Derivative contracts transfers in to Level 3 fair value hierarchy	0
Lear FAWSN
Financial Instruments [Line Items]
Previously held equity interest, fair value	23,000,000
Level 3 \| Lear FAWSN
Financial Instruments [Line Items]
Property, plant and equipment, fair value	11,000,000
Noncontrolling interest, fair value	14,000,000
Intangible assets, fair value	7,500,000
Foreign currency contract \| Derivative instruments and hedging \| Designated as hedging instrument
Financial Instruments [Line Items]
Pretax gains (losses) related to derivative instruments and hedging activities in accumulated other comprehensive loss	$ (12,800,000)	$ (18,200,000)

Financial Instruments [Line Items]

No definition available.

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- Definition

Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, including portion attributable to noncontrolling interest. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994

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- Definition

Amount of transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into level 3 of the fair value hierarchy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
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-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19279-110258

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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Fair value portion of assets, excluding financial assets, that lack physical substance, having a limited useful life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258

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- Definition

Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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