Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	$ (620,270)	$ (438,248)
Amortization	9,078	6,120
Other current period change: Currency translation adjustments and other	(35,666)	9,633
Accumulated other comprehensive loss, end of period	(646,858)	(422,495)
Currency Translation Adjustments and Other [Member]
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	(36,087)	35,875
Amortization	0	0
Other current period change: Currency translation adjustments and other	30,345	(11,681)
Accumulated other comprehensive loss, end of period	(66,432)	47,556
Net Actuarial Loss [Member]
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	(585,941)	(477,883)
Amortization	9,790	7,455
Other current period change: Net actuarial loss and prior service credit	(5,321)	(2,048)
Accumulated other comprehensive loss, end of period	(581,472)	(472,476)
Prior Service Credit [Member]
Accumulated Other Comprehensive (Loss) [Roll Forward]
Accumulated other comprehensive loss, beginning of period	1,758	3,760
Amortization	(712)	(1,335)
Other current period change: Net actuarial loss and prior service credit	0	0
Accumulated other comprehensive loss, end of period	$ 1,046	$ 2,425