Other Comprehensive Income (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (197,425)	$ (35,573)	$ (212,949)	$ (35,036)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	19,932	(854)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(5,127)	(1,268)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	719	1,585
Other Comprehensive Income (Loss), Net of Tax	15,524	(537)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(6,615)	76,629	(4,960)	77,915
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(1,655)	(1,286)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Other Comprehensive Income (Loss), Net of Tax	(1,655)	(1,286)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	12,850	(2,489)	(1,944)	(2,433)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	19,932	(854)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(817)	10
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(4,321)	788
Other Comprehensive Income (Loss), Net of Tax	14,794	(56)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(203,660)	(109,713)	$ (206,045)	$ (110,518)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(2,655)	8
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	5,040	797
Other Comprehensive Income (Loss), Net of Tax	$ 2,385	$ 805