Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance			$ (246,088)
Ending Balance	$ (249,211)		(249,211)
Cumulative currency translation adjustment [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	(139,440)	$ (83,742)	(141,255)	$ (95,485)
Other comprehensive income (loss) before reclassifications	(5,459)	(36,644)	(3,644)	(24,901)
Ending Balance	(144,899)	(120,386)	(144,899)	(120,386)
Benefit plan liabilities [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	(102,988)	(108,011)	(104,375)	(100,749)
Other comprehensive income (loss) before reclassifications	(3,225)	2,365	(2,348)	1,790
Amounts reclassified from accumulated other comprehensive income (loss)	278	586	788	(6,101)
Ending Balance	(105,935)	(105,060)	(105,935)	(105,060)
Fair value change of derivatives [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	795	2,145	(458)	(1,397)
Other comprehensive income (loss) before reclassifications	1,438	(3,080)	2,928	902
Amounts reclassified from accumulated other comprehensive income (loss)	(610)	(142)	(847)	(582)
Ending Balance	1,623	(1,077)	1,623	(1,077)
Accumulated other comprehensive loss [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Ending Balance	$ (249,211)	$ (226,523)	$ (249,211)	$ (226,523)