Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (33,183)	$ (114,576)	$ (35,036)	$ (97,461)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(281)	(653)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	1,298	(18,969)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	836	2,507
Other Comprehensive Income (Loss), Net of Tax	1,853	(17,115)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax	79,260	32,766	77,915	56,012
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	1,345	(23,246)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Other Comprehensive Income (Loss), Net of Tax	1,345	(23,246)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2,231)	(5,259)	(2,433)	(5,438)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(281)	(653)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	43	(10)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	440	842
Other Comprehensive Income (Loss), Net of Tax	202	179
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(110,212)	(142,083)	(110,518)	(148,035)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(90)	4,287
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	396	1,665
Other Comprehensive Income (Loss), Net of Tax	$ 306	$ 5,952