Derivative Instruments and Hedging Activities - Derivatives Designated as Hedging Instruments (Detail) (Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 19,945	$ 0
Derivative Assets, Fair Value	0	0
Derivative Liabilities, Fair Value	241	0
Net loss	(66)	(1,990)	(448)
Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	19,945	0
Derivative Assets, Fair Value	0	0
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Net Loss on Termination of Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swap—cash flow hedge—loss on termination	0	(1,866)	0
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swap—cash flow hedge—interest payments	66	124	448
Interest rate swap—cash flow hedge—ineffectiveness	0	0	0
Other Liabilities [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Liabilities, Fair Value	$ 241	$ 0