Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance			$ (242,563)
Ending Balance	$ (200,588)		(200,588)
Cumulative currency translation adjustment [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	(119,405)	$ (120,780)	(143,481)	$ (130,661)
Other comprehensive income (loss) before reclassifications	16,047	2,681	40,123	12,562
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Ending Balance	(103,358)	(118,099)	(103,358)	(118,099)
Benefit plan liabilities [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	(100,340)	(84,595)	(97,612)	(84,124)
Other comprehensive income (loss) before reclassifications	(1,714)	(497)	(5,428)	(1,638)
Amounts reclassified from accumulated other comprehensive income (loss)	5,677	348	6,663	1,018
Ending Balance	(96,377)	(84,744)	(96,377)	(84,744)
Fair value change of derivatives [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	113	(4,766)	(1,470)	(2,280)
Other comprehensive income (loss) before reclassifications	(619)	828	1,242	(3,803)
Amounts reclassified from accumulated other comprehensive income (loss)	(347)	1,053	(625)	3,198
Ending Balance	(853)	(2,885)	(853)	(2,885)
Accumulated other comprehensive loss [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Beginning Balance	(219,632)	(210,141)	(242,563)	(217,065)
Other comprehensive income (loss) before reclassifications	13,714	3,012	35,937	7,121
Amounts reclassified from accumulated other comprehensive income (loss)	5,330	1,401	6,038	4,216
Ending Balance	$ (200,588)	$ (205,728)	$ (200,588)	$ (205,728)