Schedule of Gains and Losses on Derivatives Designated as Cash Flow Hedges (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (loss) recognized in AOCI on derivatives (effective portion)	$ (356)	[1]	$ (174)	[1]	$ (600)	[1]	$ (344)	[1]
Gain or (loss) reclassified from AOCI into income (effective portion)	(170)	[1]	(257)	[1]	(702)	[1]	(808)	[1]
Gain or (loss) recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing)	$ (1)	[1]	$ (2)	[1]			$ (3)	[1]

[1] Losses on derivatives reclassified from accumulated other comprehensive income ("AOCI") into income (effective portion) were included in "Interest expense" in the Condensed Consolidated Statements of Operations.