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Long-Term Debt and Capital Lease Obligations - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015	Dec. 08, 2015	Dec. 31, 2014	Oct. 29, 2014
Line of Credit Facility [Line Items]
Line of Credit facility, maturity date		Oct. 29, 2019
Line of Credit facility, estimated increase in borrowings	$ 2,200,000,000
Line of credit description		At the Company’s option, borrowings under the Credit Agreement (other than swingline loans) will bear interest at (i) the Alternate Base Rate (defined as the higher of (a) the prime rate, (b) the Federal Funds Rate plus 1/2 of 1.00% and (c) LIBOR for an interest period of one month plus 1.00%) plus an applicable margin rate ranging from 0.125% to 0.750% based on the Company’s consolidated leverage ratio or (ii) the LIBOR rate plus an applicable margin rate ranging from 1.125% to 1.750% based on the Company’s consolidated leverage ratio. Swingline loans will bear interest at the alternate base rate plus the applicable margin.
Aggregate principal amount of debt		$ 1,283,500,000		$ 568,000,000
Line of Credit facility, reduction in the available balance		200,000
Line of Credit facility, available balance		$ 1,400,000,000
Minimum [Member]
Line of Credit Facility [Line Items]
Commitment fee percentage	0.15%
Maximum [Member]
Line of Credit Facility [Line Items]
Commitment fee percentage	0.30%
Alternate Base Rate [Member]
Line of Credit Facility [Line Items]
Debt instrument, interest rate		1/2 of 1.00%
Alternate Base Rate [Member] | LIBOR [Member]
Line of Credit Facility [Line Items]
Debt instrument, interest rate		LIBOR for an interest period of one month plus 1.00%
Debt instrument, variable interest rate	1.00%
Applicable Margin Rate [Member] | LIBOR [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt instrument, variable interest rate	0.125%
Applicable Margin Rate [Member] | LIBOR [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt instrument, variable interest rate	0.75%
Unsecured Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	$ 1,700,000,000				$ 1,300,000,000
Term Loan Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	200,000,000
Aggregate principal amount of debt		$ 190,000,000		$ 200,000,000
Swingline Loans [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	75,000,000
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit facility, borrowing capacity	$ 37,500,000
5.25% Senior Unsecured Notes Due 2023 [Member]
Line of Credit Facility [Line Items]
Aggregate principal amount of debt		$ 750,000,000	$ 750,000,000
Debt instrument interest rate			5.25%
Debt instrument maturity date description		Payable semi-annually in arrears on June 1 and December 1, beginning on June 1, 2016
Redemption price percentage of principal amount redeemed		100.00%
Redemption price percentage		35.00%
Redemption price percentage of aggregate principal amount redeemed		105.25%
5.25% Senior Unsecured Notes Due 2023 [Member] | Redemption in 2018 [Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		103.938%
5.25% Senior Unsecured Notes Due 2023 [Member] | Redemption in 2019[Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		102.625%
5.25% Senior Unsecured Notes Due 2023 [Member] | Redemption in 2020 [Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		101.313%
5.25% Senior Unsecured Notes Due 2023 [Member] | Redemption in 2021 and Thereafter [Member]
Line of Credit Facility [Line Items]
Redemption price percentage of principal amount redeemed		100.00%

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Line of credit facility, reduction in the available balance

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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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Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

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Date the credit facility terminates, in CCYY-MM-DD format.

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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 of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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