Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance		$ 273,456
Other Comprehensive loss		2,729	$ 2,758
Amounts reclassified from accumulated other comprehensive loss	[1]	172	146
Ending balance		286,809
Loss reclassified from AOCI for defined benefit pension plans		200	100
Tax benefit reclassified from AOCI for defined benefit pension plans		100	100
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance		(27,885)	(16,920)
Other Comprehensive loss		2,729	2,758
Amounts reclassified from accumulated other comprehensive loss	[1]	0	0
Ending balance		(25,156)	(14,162)
Defined Benefit Pension Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance		(20,065)	(17,665)
Other Comprehensive loss		0	0
Amounts reclassified from accumulated other comprehensive loss	[1]	172	146
Ending balance		(19,893)	(17,519)
Total Accumulated Other Comprehensive (Loss) Income
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance		(47,950)	(34,585)
Ending balance		$ (45,049)	$ (31,681)

[1] Amount represents amortization of actuarial losses, a component of net periodic benefit cost. This amount was $0.2 million, net of $0.1 million tax benefit, and $0.1 million, net of $0.1 million tax benefit for the quarters ended March 31, 2017 and 2016, respectively.