Summary of Changes in Reserves for Product Liability and Warranty Claims (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 28, 2013
Product Liability Contingency [Line Items]
Beginning Balance	$ 22.7
Expense, net (including changes in estimates)	9.1
Settlements	(5.1)
Foreign currency translation and other	(0.1)
Ending Balance	$ 26.6

Standard Product Warranty Accrual, Currency Translation, Increase (Decrease) and Other

No definition available.

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Namespace Prefix:	lea_
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Balance Type:	credit
Period Type:	duration

- Definition

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to product warranties (including adjustments related to changes in estimates).

+ References

No definition available.

+ Details

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Namespace Prefix:	lea_
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- Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)(1),(c)(5)

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(2))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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Balance Type:	debit
Period Type:	duration