Accumulated Other Comprehensive Income (Loss) - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance				$ 556,984
Other comprehensive income before reclassifications		$ (2,657)	$ 5,956	9,899	$ (19,224)
Amounts reclassified from AOCI	[1]	568	750	1,134	1,500
Net current-period other comprehensive income		(2,089)	6,706	11,033	(17,724)
Ending Balance		618,884		618,884
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		(75,758)	(68,051)	(88,337)	(42,914)
Other comprehensive income before reclassifications		(2,648)	5,940	9,931	(19,197)
Net current-period other comprehensive income		(2,648)	5,940	9,931	(19,197)
Ending Balance		(78,406)	(62,111)	(78,406)	(62,111)
Defined Benefit Pension Plan Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		(36,261)	(40,400)	(36,825)	(41,149)
Amounts reclassified from AOCI		565	750	1,129	1,499
Net current-period other comprehensive income		565	750	1,129	1,499
Ending Balance		(35,696)	(39,650)	(35,696)	(39,650)
Cash Flow Hedge Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		53	76	74	118
Other comprehensive income before reclassifications		(9)	16	(32)	(27)
Amounts reclassified from AOCI		3		5	1
Net current-period other comprehensive income		(6)	16	(27)	(26)
Ending Balance		47	92	47	92
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		(111,966)	(108,375)	(125,088)	(83,945)
Ending Balance		$ (114,055)	$ (101,669)	$ (114,055)	$ (101,669)

[1] Amounts in parentheses denote expense to statement of income.