Derivative Instruments - Schedule of Gain (Loss) Recognized on Derivative Instruments (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments [Line Items]
Cross-currency swap gain (loss) recorded in other comprehensive income (loss), net of taxes	$ 248	$ (279)	$ 263
Cross-currency swap [Member]
Derivative Instruments [Line Items]
Cross-currency swap gain (loss) recorded in other comprehensive income (loss), net of taxes	251	(278)	263
Warrants [Member]
Derivative Instruments [Line Items]
Warrants unrealized gain (loss) recorded in other comprehensive income (loss), net of taxes	$ (3)	$ (1)