Accumulated Other Comprehensive Loss - Summary of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 87,500
Ending Balance	98,311
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(4,583)	$ (4,049)
Other comprehensive income (loss) before reclassifications	1,639	524
Amounts reclassified from accumulated other comprehensive loss	0	0
Ending Balance	$ (2,944)	$ (3,525)