Summary of Interest Rate Swap Agreements Designated as Hedge Agreements (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014
Interest Rate Swaps [Line Items]
Nominal Amount	$ 450,000
Current Liability	5,545	[1]
Long-Term Liability	2,765	[2]
Estimated Total Fair Value at March 31, 2014	8,310
Interest Rate Swap One Agreements
Interest Rate Swaps [Line Items]
Nominal Amount	175,000
Effective Date	Dec. 01, 2010
Pay Rate	1.3975%
Receive Rate	1-Month LIBOR
Expiration Date	Sep. 01, 2015
Current Liability	2,020	[1]
Long-Term Liability	847	[2]
Estimated Total Fair Value at March 31, 2014	2,867
Interest Rate Swap Two Agreements
Interest Rate Swaps [Line Items]
Nominal Amount	175,000
Effective Date	Dec. 01, 2010
Pay Rate	1.40%
Receive Rate	1-Month LIBOR
Expiration Date	Sep. 01, 2015
Current Liability	2,040	[1]
Long-Term Liability	851	[2]
Estimated Total Fair Value at March 31, 2014	2,891
Interest Rate Swap Three Agreements
Interest Rate Swaps [Line Items]
Nominal Amount	100,000
Effective Date	Nov. 01, 2011
Pay Rate	1.715%
Receive Rate	1-Month LIBOR
Expiration Date	Apr. 01, 2016
Current Liability	1,485	[1]
Long-Term Liability	1,067	[2]
Estimated Total Fair Value at March 31, 2014	$ 2,552

[1] Included in accounts payable and accrued expenses on the condensed consolidated balance sheet as of March 31, 2014.

[2] Included in other long-term liabilities on the condensed consolidated balance sheet as of March 31, 2014.