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		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive loss before reclassifications, tax	$ 529	$ 70	$ 1,287	$ 1,461
Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive loss before reclassifications, tax	(42)	(476)	(394)	(156)
Amounts reclassified from accumulated other comprehensive loss to interest expense, tax	$ 571	$ 546	$ 1,681	$ 1,617