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

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

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-Name Accounting Standards Codification

-Topic 825

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Number 210

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-Topic 210

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

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

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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Credit Facility and Long-Term Debt (Debt Instruments) (Details) (USD $)	0 Months Ended
	Oct. 29, 2013	May 08, 2012	Mar. 27, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	$ (8,200,000)	$ (800,000)
Carrying amount			1,493,082,000us-gaap_LongTermDebt	1,492,759,000us-gaap_LongTermDebt
Proceeds from issuance of long term debt	991,800,000	499,200,000
Debt Issuance Cost	5,500,000us-gaap_DebtIssuanceCosts	3,700,000us-gaap_DebtIssuanceCosts
Senior Notes [Member] \| Two Point Five Percent Senior Notes Maturing November 15, 2018 [Member]
Debt Instrument [Line Items]
Due Date	Nov. 15, 2018
Coupon rate	2.50%
Effective interest rate	2.71%
Principal Amount	600,000,000		600,000,000	600,000,000
Debt Instrument, Unamortized Discount			(2,283,000)	(2,443,000)
Carrying amount			597,717,000	597,557,000
Debt Instrument, Fair Value Disclosure			613,746,000	606,564,000
Senior Notes [Member] \| Four Point One Percent Senior Notes Maturing November 15, 2023 [Member]
Debt Instrument [Line Items]
Due Date	Nov. 15, 2023
Coupon rate	4.10%
Effective interest rate	4.29%
Principal Amount	400,000,000		400,000,000	400,000,000
Debt Instrument, Unamortized Discount			(4,316,000)	(4,441,000)
Carrying amount			395,684,000	395,559,000
Debt Instrument, Fair Value Disclosure			427,112,000	417,480,000
Senior Notes [Member] \| One Point Seven Five Percent Senior Note Maturing May 15, 2017 [Member]
Debt Instrument [Line Items]
Due Date		May 15, 2017
Coupon rate		1.75%
Effective interest rate		1.94%
Principal Amount		500,000,000	500,000,000	500,000,000
Debt Instrument, Unamortized Discount			(319,000)	(357,000)
Carrying amount			499,681,000	499,643,000
Debt Instrument, Fair Value Disclosure			$ 503,655,000	$ 501,460,000