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Debt instrument, revolving and term loan

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Fees On Loans Maximum

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Fees On Loans Minimum

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Letter Of Credit Usage Fee Maximum

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Letter Of Credit Usage Fee Minimum

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LIBOR Rate Below Base Rate

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Line of Credit Facility, Borrowings in the Period

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Unsecured Revolving Credit Facility

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 835
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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of the required periodic payments applied to principal.

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- Definition

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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No definition available.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Carrying value as of the balance sheet date of the portion of long-term notes having the highest claim on the assets of the issuer in case of bankruptcy or liquidation, due within one year or the normal operating cycle, if longer. Senior note holders are paid off in full before any payments are made to debt holders having a lesser priority of repayment.

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

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Long-Term Debt - Narrative (Detail)			3 Months Ended
Long-Term Debt - Narrative (Detail)	Sep. 18, 2014 USD ($)	May 20, 2014 extension	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Jan. 15, 2015 USD ($)	Apr. 17, 2014 USD ($)	Sep. 15, 2011 USD ($)	Feb. 01, 2008 USD ($)	Dec. 22, 2006 USD ($)
Debt Instrument [Line Items]
Revolving and term loan			$ 50,000,000.0
Potential increased in line of credit facility							$ 500,000,000.0
Unsecured revolving credit facility							800,000,000.0
Unsecured term loans							550,000,000.0
Outstanding debt balance			1,138,819,000		$ 1,144,743,000
5.660% senior notes, Series C, semi-annual interest payments, balloon due 2016
Debt Instrument [Line Items]
Current portion of senior notes			25,000,000		25,000,000	$ 25,000,000
Credit Agreement
Debt Instrument [Line Items]
Number of extension periods \| extension		2
Extension period		1 year
Unsecured revolving credit facility							$ 1,350,000,000.0
First principal payment			13,800,000
Unsecured Senior Notes
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage	4.20%
Debt instrument, face amount	$ 500,000,000.0
Debt instrument maturity year	2024
Outstanding debt balance			$ 500,000,000		500,000,000
Wells Fargo Revolver
Debt Instrument [Line Items]
Debt instrument, maturity date			Dec. 31, 2016
Potential increased in line of credit facility			$ 75,000,000.0
Borrowings outstanding			$ 0
Line of Credit \| Wells Fargo Revolver
Debt Instrument [Line Items]
Letter of credit usage fee, minimum			1.00%
Letter of credit usage fee, maximum			1.40%
LIBOR below base rate			1.00%
Availability fees, minimum			0.175%
Availability fees, maximum			0.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Proceeds from lines of credit			$ 0	$ 0
Master Agreement
Debt Instrument [Line Items]
Unsecured senior notes outstanding			125,000,000
Master Agreement \| Series C
Debt Instrument [Line Items]
Unsecured senior notes outstanding									$ 25,000,000.0	$ 25,000,000.0
Debt instrument interest rate stated percentage										5.66%
Master Agreement \| Series D
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage									5.37%
Master Agreement \| Series E
Debt Instrument [Line Items]
Unsecured senior notes outstanding								$ 100,000,000.0
Debt instrument interest rate stated percentage								4.50%
New Master Agreement [Member]
Debt Instrument [Line Items]
Unsecured senior notes outstanding			$ 1,138,819,000		$ 1,153,003,000
LIBOR
Debt Instrument [Line Items]
30-day Adjusted LIBOR Rate			0.44%
Minimum \| Revolving Credit Facility
Debt Instrument [Line Items]
Facility fee			0.15%
Minimum \| LIBOR \| Term Loan
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.00%
Minimum \| LIBOR \| Line of Credit \| Wells Fargo Revolver
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.00%
Minimum \| LIBOR \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, variable interest rate			0.85%
Maximum \| Revolving Credit Facility
Debt Instrument [Line Items]
Facility fee			0.25%
Maximum \| LIBOR \| Term Loan
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.75%
Maximum \| LIBOR \| Line of Credit \| Wells Fargo Revolver
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.40%
Maximum \| LIBOR \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.50%