Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Marketable securities, Balance at beginning of period	$ 39,968	$ 47,305	$ 47,112	$ 154,169
Other comprehensive income (loss) - unrealized gains (losses) arising during the year	(34,513)	1,022	(41,657)	(105,842)
Marketable securities, Balance at end of period	5,455	48,327	5,455	48,327
Currency translation, Balance at beginning of period	(165,944)	(135,190)	(154,173)	(133,816)
Other comprehensive loss	(3,538)	(9,215)	(15,309)	(10,589)
Currency translation, Balance at end of period	(169,482)	(144,405)	(169,482)	(144,405)
Other comprehensive loss	(733)		(733)
Interest rate swap, Balance at end of period	(733)		(733)
Balance at beginning of period	(199,406)	(142,512)	(182,039)	(35,016)
Other comprehensive loss, net of tax	(38,019)	(7,819)	(55,386)	(115,315)
Balance at end of period	(237,425)	(150,331)	(237,425)	(150,331)
Defined Benefit Pension Plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(73,439)	(55,589)	(75,260)	(56,644)
Defined benefit pension plans/ Other postretirement benefit plans	902	530	2,723	1,585
Balance at end of period	(72,537)	(55,059)	(72,537)	(55,059)
OPEB
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	9	962	282	1,275
Defined benefit pension plans/ Other postretirement benefit plans	(137)	(156)	(410)	(469)
Balance at end of period	$ (128)	$ 806	$ (128)	$ 806