Derivative Financial Instruments - Summary of Effect of Derivative Financial Instruments on Consolidated Statements of Operations (Detail) (Interest Rate Contracts, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	$ (1,465)	$ (699)
Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion)	(756)	(753)
Derivative Assets
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	(537)	(561)
Derivative Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	(928)	(138)
Interest Expense | Derivative Assets
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion)	(288)	(286)
Interest Expense | Derivative Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion)	$ (468)	$ (467)