Accumulated Other Comprehensive Loss - Net Change and Ending Balances for Various Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 161,761
Net Change	1,691	$ 2,978
Ending Balance	165,286
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(11,932)	(22,973)
Net Change	2,498	2,252
Ending Balance	(9,434)	(20,721)
Foreign Currency Translation Adjustments [Member] | Cumulative Effect of ASU 2016-01 [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	0
Foreign Currency Translation Adjustments [Member] | Previously Reported [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(11,932)
Unrecognized Employee Benefit Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(34,196)	(38,636)
Net Change	(283)	478
Ending Balance	(34,479)	(38,158)
Unrecognized Employee Benefit Costs [Member] | Cumulative Effect of ASU 2016-01 [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	0
Unrecognized Employee Benefit Costs [Member] | Previously Reported [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(34,196)
Unrealized Holding Gains on Marketable Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	0	59
Net Change	0	179
Ending Balance	0	238
Unrealized Holding Gains on Marketable Securities [Member] | Cumulative Effect of ASU 2016-01 [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(632)
Unrealized Holding Gains on Marketable Securities [Member] | Previously Reported [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	632
Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	739	551
Net Change	(524)	69
Ending Balance	215	620
Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member] | Cumulative Effect of ASU 2016-01 [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	0
Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member] | Previously Reported [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	739
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(45,389)	(60,999)
Net Change	1,691	2,978
Ending Balance	(43,698)	$ (58,021)
AOCI Including Portion Attributable to Noncontrolling Interest [Member] | Cumulative Effect of ASU 2016-01 [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(632)
AOCI Including Portion Attributable to Noncontrolling Interest [Member] | Previously Reported [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ (44,757)