Accumulated Comprehensive Loss - Related Tax Effects Allocated to Each Component of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity [Abstract]
Net actuarial gain (loss) and prior service credit, before tax amount	$ (6,553)	$ 2,169
Reclassification of actuarial loss and prior service cost to net income, before tax amount	507	616
Total recognized in other comprehensive income (loss)	(6,046)	2,785
Cumulative translation adjustment, before tax amount	(3,235)	(4,596)
Total other comprehensive income (loss), before tax amount	(9,281)	(1,811)
Net actuarial gain (loss) and prior service credit, tax	206	(449)
Reclassification of actuarial loss and prior service cost to net income, tax	(117)	(130)
Net unrealized loss, before tax amount, tax	89	(579)
Cumulative translation adjustment, tax	1	24
Total other comprehensive income (loss), tax	90	(555)
Net actuarial gain (loss) and prior service credit, after tax amount	(6,347)	1,720
Reclassification of actuarial loss and prior service cost to net income, after tax amount	390	486
Net unrealized loss, before tax amount, after tax amount	(5,957)	2,206
Cumulative translation adjustment, after tax amount	(3,234)	(4,572)	$ (4,600)
Total other comprehensive income (loss), after tax amount	$ (9,191)	$ (2,366)