Changes in Accumulated Income (Loss) by Component (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss),Beginning Balance	$ (67,483)	$ (51,825)
Other comprehensive income (loss) before reclassifications	5,602	8,181
Other Comprehensive Income (Loss) before Reclassifications, Tax	0	0
Other comprehensive income (loss) before reclassifications, net of tax	5,602	8,181
Amounts reclassified from accumulated other comprehensive income (loss)	462	409
Reclassification from AOCI, Current Period, Tax	(226)	(171)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	236	238
Total other comprehensive income, net of tax	5,838	8,419
Accumulated other comprehensive income (loss),Ending Balance	(61,645)	(43,406)
Retirement Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss),Beginning Balance	(11,209)	(10,482)
Other comprehensive income (loss) before reclassifications	0	0
Other Comprehensive Income (Loss) before Reclassifications, Tax	0	0
Other comprehensive income (loss) before reclassifications, net of tax	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	462	409
Reclassification from AOCI, Current Period, Tax	(226)	(171)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	236	238
Total other comprehensive income, net of tax	236	238
Accumulated other comprehensive income (loss),Ending Balance	(10,973)	(10,244)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss),Beginning Balance	(56,245)	(41,228)
Other comprehensive income (loss) before reclassifications	5,492	8,162
Other Comprehensive Income (Loss) before Reclassifications, Tax	0	0
Other comprehensive income (loss) before reclassifications, net of tax	5,492	8,162
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Reclassification from AOCI, Current Period, Tax	0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	0	0
Total other comprehensive income, net of tax	5,492	8,162
Accumulated other comprehensive income (loss),Ending Balance	(50,753)	(33,066)
Other
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss),Beginning Balance	(29)	(115)
Other comprehensive income (loss) before reclassifications	110	19
Other Comprehensive Income (Loss) before Reclassifications, Tax	0	0
Other comprehensive income (loss) before reclassifications, net of tax	110	19
Amounts reclassified from accumulated other comprehensive income (loss)
Reclassification from AOCI, Current Period, Tax	0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	0	0
Total other comprehensive income, net of tax	110	19
Accumulated other comprehensive income (loss),Ending Balance	$ 81	$ (96)