Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	$ 57,372	$ 14,592
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	(620,270)	(438,248)
Amortization	4,610	3,127
Accumulated other comprehensive loss, end of period	(673,032)	(449,713)
Currency Translation Adjustments and Other [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	57,372	14,592
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	(36,087)	35,875
Accumulated other comprehensive loss, end of period	(93,459)	21,283
Net Actuarial Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	0
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	(585,941)	(477,883)
Amortization	4,961	3,807
Accumulated other comprehensive loss, end of period	(580,980)	(474,076)
Prior Service Credit [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	0
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	1,758	3,760
Amortization	(351)	(680)
Accumulated other comprehensive loss, end of period	$ 1,407	$ 3,080