Accumulated Other Comprehensive Income (Loss) (AOCI balances) (Details 2) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income, beginning balance			$ 453,480
Other comprehensive (loss) income before reclassifications			(26,414)
Net amount reclassified from accumulated other comprehensive income			3,084
Other Comprehensive Loss, Net of Tax	$ (4,713)	$ (8,314)	(23,330)	$ (151,609)
Accumulated Other Comprehensive Income, ending balance	430,150		430,150
Cumulative Foreign Currency Translation Adjustment [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income, beginning balance			8,548
Other comprehensive (loss) income before reclassifications			(17,387)
Net amount reclassified from accumulated other comprehensive income			5,501
Other Comprehensive Loss, Net of Tax			(11,886)
Accumulated Other Comprehensive Income, ending balance	(3,338)		(3,338)
Unrealized Gain on Available-for-Sale Securities [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income, beginning balance			52,130
Other comprehensive (loss) income before reclassifications			(9,898)
Net amount reclassified from accumulated other comprehensive income			0
Other Comprehensive Loss, Net of Tax			(9,898)
Accumulated Other Comprehensive Income, ending balance	42,232		42,232
Unrealized Gain on Pensions and Other Postretirement Plans [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income, beginning balance			392,910
Other comprehensive (loss) income before reclassifications			842
Net amount reclassified from accumulated other comprehensive income			(2,496)
Other Comprehensive Loss, Net of Tax			(1,654)
Accumulated Other Comprehensive Income, ending balance	391,256		391,256
Cash Flow Hedge [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income, beginning balance			(108)
Other comprehensive (loss) income before reclassifications			29
Net amount reclassified from accumulated other comprehensive income			79
Other Comprehensive Loss, Net of Tax			108
Accumulated Other Comprehensive Income, ending balance	$ 0		$ 0