Changes in Accumulated Other Comprehensive Income (Loss) by Component - Cumulative Other Comprehensive Loss in Accompanying Consolidated Statements of Equity (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 1,172,043
Other comprehensive (loss) income before reclassifications	7,145	$ 21,571
Foreign currency translation effect	(1,460)	(2,900)
Income tax effect	245	(416)
Income tax effect	(1,953)	(2,382)
Other comprehensive (loss) income	13,170	26,576
Ending balance	1,186,640
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(461,589)	(478,478)
Ending balance	(448,419)	(451,902)
Cumulative Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(62,133)	(39,940)
Other comprehensive (loss) income before reclassifications	8,328	20,925
Other comprehensive (loss) income	8,328	20,925
Ending balance	(53,805)	(19,015)
Derivative Instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	2,150	349
Other comprehensive (loss) income before reclassifications	(1,183)	646
Income tax effect	245	(416)
Amount reclassified from accumulated other comprehensive income (loss)	62	1,493
Income tax effect	88	(172)
Other comprehensive (loss) income	(788)	1,551
Ending balance	1,362	1,900
Post- retirement Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(401,606)	(438,887)
Foreign currency translation effect	(1,460)	(2,900)
Income tax effect	(2,041)	(2,210)
Other comprehensive (loss) income	5,630	4,100
Ending balance	(395,976)	(434,787)
Net Prior Service
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Amount reclassified from accumulated other comprehensive income (loss)	(102)	(135)
Actuarial Gain (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Amount reclassified from accumulated other comprehensive income (loss)	$ 9,233	$ 9,345