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

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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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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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Long-Term Debt - Narrative (Detail)				6 Months Ended		12 Months Ended
Long-Term Debt - Narrative (Detail)	Sep. 18, 2014 USD ($)	May 20, 2014 USD ($) extension	Oct. 12, 2012 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	Jan. 15, 2015 USD ($)	Apr. 17, 2014 USD ($)	Apr. 16, 2014 USD ($)	Apr. 15, 2014 USD ($)	Jul. 01, 2013 USD ($)	Sep. 15, 2011 USD ($)	Feb. 01, 2008 USD ($)	Dec. 22, 2006 USD ($)
Debt Instrument [Line Items]
Credit facility, outstanding amount				$ 508,750,000		$ 529,375,000			$ 25,000,000.0
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
Proceeds from lines of credit				0	$ 375,000,000
Outstanding debt balance				$ 1,166,675,000		$ 1,198,471,000
5.370% senior notes, Series D, quarterly interest payments, balloon due 2015
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage				5.37%		5.37%
Current portion of senior notes				$ 0		$ 25,000,000	$ 25,000,000
Debt instrument maturity year				2015		2015
Credit Agreement
Debt Instrument [Line Items]
Credit facility, outstanding amount				$ 543,100,000		$ 550,000,000
Number of extension periods \| extension		2
Extension period		1 year
Unsecured revolving credit facility								$ 1,350,000,000.0
First principal payment				6,900,000
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		0
Wells Fargo Revolver \| Beecher Acquisition
Debt Instrument [Line Items]
Credit facility, outstanding amount										$ 50,000,000.0	$ 50,000,000.0
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%
Term Loan
Debt Instrument [Line Items]
Credit facility, outstanding amount		$ 550,000,000.0
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, outstanding amount	$ 475,000,000	$ 375,000,000
Proceeds from lines of credit				$ 0		0
Uncommitted Facility \| New Master Agreement
Debt Instrument [Line Items]
Credit facility, outstanding amount				$ 0		$ 0
Potential increased in line of credit facility			$ 125,000,000
Issuance period			3 years
Maturity period				10 years
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%
LIBOR
Debt Instrument [Line Items]
30-day Adjusted LIBOR Rate				0.19%
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%