Financial Instruments [Line Items]

No definition available.

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- Definition

Intangible Assets (Excluding Goodwill), Fair Value Disclosure

+ References

No definition available.

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- Definition

Uncommitted Factoring Agreement, Aggregate Purchase of Customer Accounts

+ References

No definition available.

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19279-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19279-110258

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258

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- Definition

Gain relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

+ Details

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- Definition

The net gain (loss) relating to components of the gain (loss) on the cash flow hedging instrument excluded from the assessment of cash flow hedge effectiveness. Recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Amount of investments in equity securities and other forms of securities that provide ownership interests expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

No definition available.

+ Details

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

+ Details

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Financial Instruments - Additional Information (Detail)		3 Months Ended		9 Months Ended
Financial Instruments - Additional Information (Detail)	Sep. 07, 2017 USD ($)	Sep. 30, 2017 USD ($)	Oct. 01, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2017 EUR (€)	Oct. 01, 2016 USD ($)	Dec. 31, 2016 USD ($)
Financial Instruments [Line Items]
Uncommitted factoring agreement, aggregate purchases of specified customer accounts (up to) \| €					€ 200,000,000
Factored receivables outstanding		$ 0		$ 0
Gain (loss) expected to be reclassified into earnings from accumulated other comprehensive loss				14,600,000
Gain (loss) recognized related to components excluded from effectiveness assessments, cash flow hedges		0	$ 0	0		$ 0
Gain (loss) on hedge ineffectiveness, cash flow hedges		0	0	0		0
Gain (loss) recognized related to components excluded from effectiveness assessments, fair value hedges		0	0	0		0
Gain (loss) on hedge ineffectiveness, fair value hedges		0	$ 0	0		$ 0
Derivative contracts classified within Level 3 of fair value hierarchy		0		0			$ 0
Derivative contracts transfers in to Level 3 fair value hierarchy				0
Shanghai Lear Stec Automotive Parts Co Limited
Financial Instruments [Line Items]
Noncontrolling interest, fair value	$ 125,000,000
Previously held equity interest, fair value	$ 94,000,000
Level 1 \| Recurring
Financial Instruments [Line Items]
Marketable equity securities		40,700,000		40,700,000			30,200,000
Level 3 \| Shanghai Lear Stec Automotive Parts Co Limited
Financial Instruments [Line Items]
Property, plant and equipment, fair value		16,200,000		16,200,000
Noncontrolling interest, fair value		125,000,000		125,000,000
Previously held equity interest, fair value				94,000,000
Level 3 \| Shanghai Lear Stec Automotive Parts Co Limited \| Customer-based intangible assets
Financial Instruments [Line Items]
Customer-based intangible assets, fair value		66,000,000		66,000,000
Level 3 \| Antolin Seating
Financial Instruments [Line Items]
Property, plant and equipment, fair value		81,700,000		81,700,000
Intangible assets, fair value		121,400,000		121,400,000
Level 3 \| AccuMED
Financial Instruments [Line Items]
Property, plant and equipment, fair value		11,200,000		11,200,000			13,900,000
Intangible assets, fair value		53,000,000		53,000,000			53,000,000
Foreign currency contract \| Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest \| Designated as hedging instrument
Financial Instruments [Line Items]
Pretax gains (losses) related to derivative instruments and hedging activities in accumulated other comprehensive loss		$ 19,500,000		$ 19,500,000			$ (56,500,000)