Changes in Accumulated Other Comprehensive Loss, Net of Taxes, Related to Interest Rate Swap Agreements (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	$ 391	$ 963	$ 759	$ 1,391
Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	504	(75)	1,010	334
Amounts reclassified from accumulated other comprehensive loss to interest expense, tax	$ 895	$ 888	$ 1,769	$ 1,725