Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
AOCI Attributable to Parent [Roll Forward]
Beginning balance, January 1			$ 3,146,567
Total other comprehensive (loss) income	$ (19,646)	$ 18,181	48,453	$ (89,290)
June 30, 2016	3,237,619		3,237,619
Pension and Other Post-Retirement Benefits [Member]
AOCI Attributable to Parent [Roll Forward]
Beginning balance, January 1			(535,634)	(533,213)
Other comprehensive income before reclassifications, net of tax			0	0
Amounts reclassified from accumulated other comprehensive loss, net of tax			9,509	11,704
Total other comprehensive (loss) income			9,509	11,704
June 30, 2016	(526,125)	(521,509)	(526,125)	(521,509)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent [Roll Forward]
Beginning balance, January 1			(394,984)	(186,998)
Other comprehensive income before reclassifications, net of tax			38,944	(100,994)
Amounts reclassified from accumulated other comprehensive loss, net of tax			0	0
Total other comprehensive (loss) income			38,944	(100,994)
June 30, 2016	(356,040)	(287,992)	(356,040)	(287,992)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent [Roll Forward]
Beginning balance, January 1			(930,618)	(720,211)
Other comprehensive income before reclassifications, net of tax			38,944	(100,994)
Amounts reclassified from accumulated other comprehensive loss, net of tax			9,509	11,704
Total other comprehensive (loss) income			48,453	(89,290)
June 30, 2016	$ (882,165)	$ (809,501)	$ (882,165)	$ (809,501)