Percentage of stock of subsidiaries that secure on a first priority basis of the Amended and Restated Credit Agreement.

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Percentage ownership by Lear of domestic subsidiaries who are guarantors

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Restricted Cash Disbursements for Repayments of Senior Debt

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Restricted Cash Disbursements to Acquire Businesses, Gross

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Maximum contractual interest rate for funds borrowed, under the debt agreement.

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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Percentage of principal amount of debt redeemed.

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Face (par) amount of the original debt instrument that was repurchased.

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The net cash inflow or outflow in other borrowings not otherwise defined in the taxonomy.

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The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Debt - Additional Information (Detail)		1 Months Ended				3 Months Ended			9 Months Ended
Debt - Additional Information (Detail)	Jan. 05, 2015 USD ($)	Mar. 28, 2015 USD ($)	Jan. 31, 2015 USD ($)	Nov. 30, 2014 USD ($)	Mar. 29, 2014 USD ($)	Sep. 26, 2015 USD ($)	Mar. 28, 2015 USD ($)	Mar. 29, 2014 USD ($)	Sep. 26, 2015 USD ($)	Sep. 27, 2014 USD ($)	Dec. 31, 2014 USD ($)	Oct. 31, 2014 USD ($)
Debt Instrument [Line Items]
Cash restricted for use - repurchase of senior notes									$ 250,000,000	$ 0
Cash restricted for use - acquisition of Eagle Ottawa									$ 350,000,000	0
Percentage owned, domestic subsidiaries									1
Proceeds from borrowings under Term Loan Facility									$ 500,000,000	0
Repayments under Term Loan Facility									3,100,000	$ 0
Eagle Ottawa
Debt Instrument [Line Items]
Restricted cash used to finance the acquisition	$ 350,000,000
4.75% Senior Notes due 2023 \| Senior notes
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount						$ 500,000,000			$ 500,000,000
Long-term debt, stated coupon rate						4.75%			4.75%		4.75%
5.375% Senior Notes due 2024 \| Senior notes
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount						$ 325,000,000			$ 325,000,000
Long-term debt, stated coupon rate						5.375%			5.375%		5.375%
Proceeds from offering					$ 325,000,000
Debt issuance cost					$ 3,800,000
5.375% Senior Notes due 2024 \| Senior notes \| Unsecured Debt
Debt Instrument [Line Items]
Cash paid for debt redemption								$ 327,100,000
Gain (loss) on extinguishment of debt								$ (17,500,000)
7.875% Senior Notes due 2018 \| Senior notes
Debt Instrument [Line Items]
Long-term debt, stated coupon rate					7.875%			7.875%
Payment for redemption of aggregate principal amount					$ 280,000,000			$ 280,000,000
8.125% Senior Notes due 2020 \| Senior notes
Debt Instrument [Line Items]
Long-term debt, stated coupon rate						8.125%			8.125%		8.125%
Payment for redemption of aggregate principal amount					$ 35,000,000	$ 245,000,000		$ 35,000,000	$ 245,000,000
Percentage of debt redemption		104.063%			10.00%
Cash restricted for use - repurchase of senior notes		$ 250,000,000							250,000,000
8.125% Senior Notes due 2020 \| Senior notes \| Unsecured Debt
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt							$ (14,300,000)
Repayments of debt		$ 255,000,000
5.25% Senior Notes due 2025 \| Eagle Ottawa
Debt Instrument [Line Items]
Cash restricted for use - acquisition of Eagle Ottawa	350,000,000
Restricted cash used to finance the acquisition	$ 350,000,000
5.25% Senior Notes due 2025 \| Senior notes
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount						$ 650,000,000			$ 650,000,000
Long-term debt, stated coupon rate				5.25%		5.25%			5.25%		5.25%
Proceeds from offering				$ 650,000,000
Debt issuance cost				8,400,000
Credit Agreement — Term Loan Facility \| Term Loan Facility
Debt Instrument [Line Items]
Credit agreement borrowings				500,000,000
Long-term debt, aggregate principal amount				500,000,000
Repayments under Term Loan Facility						$ 3,100,000
Credit Agreement — Term Loan Facility \| Term Loan Facility \| Eurocurrency Rate
Debt Instrument [Line Items]
Minimum interest rate margin									1.25%
Maximum interest rate margin									2.25%
Line of credit facility, interest rate at period end						1.50%			1.50%
Credit Agreement — Term Loan Facility \| Term Loan Facility \| Adjusted Base Rate
Debt Instrument [Line Items]
Minimum interest rate margin									0.25%
Maximum interest rate margin									1.25%
Line of credit facility, interest rate at period end						0.50%			0.50%
Credit Agreement — Term Loan Facility \| Eagle Ottawa \| Term Loan Facility
Debt Instrument [Line Items]
Proceeds from borrowings under Term Loan Facility			$ 500,000,000
Credit agreement- revolving credit facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity				$ 1,250,000,000.00								$ 1,000,000,000.0
Credit agreement- revolving credit facility \| Minimum
Debt Instrument [Line Items]
Line of credit facility, facility fee									0.25%
Credit agreement- revolving credit facility \| Maximum
Debt Instrument [Line Items]
Line of credit facility, facility fee									0.50%
Credit agreement- revolving credit facility \| Eurocurrency Rate
Debt Instrument [Line Items]
Minimum interest rate margin									1.00%
Maximum interest rate margin									2.25%
Line of credit facility, interest rate at period end						1.50%			1.50%
Credit agreement- revolving credit facility \| Adjusted Base Rate
Debt Instrument [Line Items]
Minimum interest rate margin									0.00%
Maximum interest rate margin									1.25%
Line of credit facility, interest rate at period end						0.50%			0.50%
Credit agreement- revolving credit facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings outstanding under revolving credit facility						$ 0			$ 0		$ 0
Credit Agreement \| Domestic subsidiaries
Debt Instrument [Line Items]
Percentage of stock secured on a first priority basis						100.00%			100.00%
Credit Agreement \| Foreign subsidiaries
Debt Instrument [Line Items]
Percentage of stock secured on a first priority basis						65.00%			65.00%