Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ 177,920
Other comprehensive income (loss)	980	$ 1,404
Balance at end of period	187,250
Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	20,473	195
Other comprehensive income (loss)	(1,722)	(1,531)
Balance at end of period	18,751	(1,336)
Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(175,859)	(172,384)
Other comprehensive income (loss)	1,771	2,831
Balance at end of period	(174,088)	(169,553)
Interest Rate Swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(390)	(445)
Other comprehensive income (loss)	1	(683)
Less reclassification adjustment for amounts included in interest expense	111	112
Balance at end of period	(278)	(1,016)
Accumulated Defined Benefit Plans Adjustment | Defined Benefit Pension Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(76,710)	(72,712)
Other comprehensive income (loss)	867	807
Balance at end of period	(75,843)	(71,905)
Accumulated Defined Benefit Plans Adjustment | OPEB
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(360)	(12)
Other comprehensive income (loss)	(48)	(132)
Balance at end of period	(408)	(144)
Total Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(232,846)	(245,358)
Balance at end of period	$ (231,866)	$ (243,954)