Accumulated Other Comprehensive Income (Loss) - Summary of Changes in Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			$ 891,783
Other comprehensive income before reclassifications	$ 3,537	$ 4,317	(37,645)	$ 8,004
Amounts reclassified from AOCI	806	540	1,612	1,081
Remeasurement adjustment related to the Tax Act (1)				(5,325)
Net current-period other comprehensive income	4,343	4,857	(36,033)	3,760
Ending Balance	897,429		897,429
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(145,219)	(104,794)	(104,037)	(108,481)
Other comprehensive income before reclassifications	3,537	4,317	(37,645)	8,004
Net current-period other comprehensive income	3,537	4,317	(37,645)	8,004
Ending Balance	(141,682)	(100,477)	(141,682)	(100,477)
Defined Benefit Pension Plan Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(31,397)	(37,865)	(32,205)	(33,083)
Amounts reclassified from AOCI	808	542	1,616	1,085
Remeasurement adjustment related to the Tax Act (1)				(5,325)
Net current-period other comprehensive income	808	542	1,616	(4,240)
Ending Balance	(30,589)	(37,323)	(30,589)	(37,323)
Cash Flow Hedge Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	70	79	72	81
Amounts reclassified from AOCI	(2)	(2)	(4)	(4)
Net current-period other comprehensive income	(2)	(2)	(4)	(4)
Ending Balance	68	77	68	77
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(176,546)	(142,580)	(136,170)	(141,483)
Ending Balance	$ (172,203)	$ (137,723)	$ (172,203)	$ (137,723)

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