Number of shares of common stock issuable upon exercise of warrants.

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- Definition

Common Stock, Votes per share

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- Definition

Excess Shares Delivered Under ASR

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- Definition

Treasury stock percentage acquired.

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- Definition

Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 25

-Paragraph 5

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- Definition

The price paid per share to immediately purchase the targeted number of shares on the date of executing the accelerated share repurchase agreement.

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- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

Number of warrants or rights outstanding.

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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- Definition

The cash outflow to reacquire common stock during the period.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Amount of decrease of par value, additional paid in capital (APIC) and retained earnings of common and preferred stock retired from treasury when treasury stock is accounted for under the cost method.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Number of shares of common and preferred stock retired from treasury during the period.

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Capital Stock and Equity - Capital Stock and Equity - Additional Information (Detail) (USD $)	3 Months Ended									12 Months Ended			48 Months Ended
	Dec. 31, 2014 Vote	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 31, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 31, 2012	Dec. 31, 2014 Vote	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014 Vote	Nov. 09, 2009	Mar. 31, 2014	Apr. 25, 2013
Stockholders Equity Note [Line Items]
Common stock, shares authorized	300,000,000us-gaap_CommonStockSharesAuthorized				300,000,000us-gaap_CommonStockSharesAuthorized					300,000,000us-gaap_CommonStockSharesAuthorized	300,000,000us-gaap_CommonStockSharesAuthorized		300,000,000us-gaap_CommonStockSharesAuthorized
Common stock holders voting right, vote per outstanding share	1lea_CommonStockVotesPerShare									1lea_CommonStockVotesPerShare			1lea_CommonStockVotesPerShare
Common stock, aggregate authorized repurchase amount	$ 2,250,000,000.00									$ 2,250,000,000.00			$ 2,250,000,000.00
Amount paid in accelerated stock repurchase agreement			55,500,000
Common stock, repurchased										3,805,114us-gaap_TreasuryStockSharesAcquired	15,533,758us-gaap_TreasuryStockSharesAcquired	5,357,443us-gaap_TreasuryStockSharesAcquired
Common stock, share repurchase program amount	338,600,000									338,600,000			338,600,000
Common stock, at an average purchase price excluding commission										$ 93.52	$ 54.08	$ 41.59	$ 61.97
Repurchase of common stock										411,400,000	1,000,100,000	222,800,000	1,900,000,000
Treasury stock, shares retired										8,000,000us-gaap_TreasuryStockSharesRetired	20,000,000us-gaap_TreasuryStockSharesRetired
Cash dividends declared per share	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.17	$ 0.17	$ 0.17	$ 0.17	$ 0.14
Dividends declared to Lear Corporation stockholders										67,100,000us-gaap_DividendsCommonStockCash	59,400,000us-gaap_DividendsCommonStockCash	56,100,000us-gaap_DividendsCommonStockCash
Dividends paid to Lear Corporation stockholders										65,300,000us-gaap_PaymentsOfDividendsCommonStock	58,400,000us-gaap_PaymentsOfDividendsCommonStock	54,600,000us-gaap_PaymentsOfDividendsCommonStock
Warrants outstanding					279,094						279,094			8,157,249
Exercisable of warrants into common stock					558,188						558,188
Number of shares called by warrants	2									2			2
Exercise price of warrants	$ 0.005									$ 0.005			$ 0.005
Additional paid-in capital
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury											389,700,000
Common stock
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury											200,000
Retained earnings
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury											600,700,000
Treasury stock
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury											(990,600,000)
Open market repurchases
Stockholders Equity Note [Line Items]
Repurchase of common stock										355,900,000
Accelerated share repurchase agreement \| Share repurchase program
Stockholders Equity Note [Line Items]
Common stock, aggregate authorized repurchase amount																800,000,000
Amount paid in accelerated stock repurchase agreement	855,500,000		55,500,000				800,000,000			855,500,000			855,500,000
Final price paid per share										$ 72.11
Common stock, repurchased							11,862,836
Excess shares delivered under ASR															658,903
Percentage of treasury stock repurchased							80.00%
Value of common stock repurchased, per share							$ 53.95
Treasury stock
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury										(519,900,000)	(990,600,000)
Retained earnings
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury										363,900,000	600,700,000
Dividends declared to Lear Corporation stockholders										67,100,000	59,400,000	56,100,000
Additional paid-in capital
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury										155,900,000	389,700,000
Common stock
Stockholders Equity Note [Line Items]
Retirement of shares held in treasury										$ 100,000	$ 200,000