Changes in Cumulative Other Comprehensive Loss by Component - Changes in Cumulative Other Comprehensive Loss by Component (Detail) (USD $) In Thousands, unless otherwise specified			3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Cumulative Currency Translation Adjustment [Member]	Sep. 30, 2014 Cumulative Currency Translation Adjustment [Member]	Sep. 30, 2014 Changes in the Fair Value of Derivatives [Member]	Sep. 30, 2014 Changes in the Fair Value of Derivatives [Member]	Sep. 30, 2014 Unrecognized Postretirement Benefit Plans [Member]	Sep. 30, 2014 Unrecognized Postretirement Benefit Plans [Member]	Sep. 30, 2014 Cumulative Other Comprehensive Income (Loss) [Member]	Sep. 30, 2014 Cumulative Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (399,678)	$ (410,020)	$ 61,440	$ 59,660	$ (288)	$ 1,615	$ (462,721)	$ (471,295)	$ (401,569)	$ (410,020)
Other comprehensive income (loss) before reclassifications			(12,456)	(10,676)	3,632	2,591	5,435	2,193	(3,389)	(5,892)
Amount reclassified from accumulated other comprehensive loss					(651)	(1,513)	5,931	17,747	5,280	16,234
Net current-period other comprehensive income			(12,456)	(10,676)	2,981	1,078	11,366	19,940	1,891	10,342
Ending balance	$ (399,678)	$ (410,020)	$ 48,984	$ 48,984	$ 2,693	$ 2,693	$ (451,355)	$ (451,355)	$ (399,678)	$ (399,678)