Derivative Instruments - Gains (Losses) on Derivative Instruments and Classification on Condensed Consolidated Statement of Operations (Detail) - Designated As Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Derivatives, Fair Value [Line Items]
Gains recognized in OCI	$ 458	$ 0	$ 1,774	$ 780
Losses recognized in OCI		(312)	(1,005)	(762)
Gains recognized from accumulated OCI into net loss	108	0	257	0
Losses recognized from accumulated OCI into net loss	$ (2)	$ (113)	$ (243)	$ (684)