Accumulated Other Comprehensive Income (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			$ 188,561	$ (103,660)
Other comprehensive income (loss) before reclassifications			(34,738)	66,817
Reclassifications into earnings			16,660	14,001
Other comprehensive (loss) income, net of tax	$ (38,256)	$ 54,510	(18,078)	80,818
Balances, end of period	195,917	29,373	195,917	29,373
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(406)	(1,485)
Other comprehensive income (loss) before reclassifications			(511)	(141)
Reclassifications into earnings			762	524
Other comprehensive (loss) income, net of tax			251	383
Balances, end of period	(155)	(1,102)	(155)	(1,102)
Available for sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			1,597	120
Other comprehensive income (loss) before reclassifications			(5,154)	1,734
Reclassifications into earnings			(142)	142
Other comprehensive (loss) income, net of tax			(5,296)	1,876
Balances, end of period	(3,699)	1,996	(3,699)	1,996
Pension and postretirement benefit plans
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(748,800)	(787,813)
Other comprehensive income (loss) before reclassifications			0	(1,482)
Reclassifications into earnings			16,040	13,335
Other comprehensive (loss) income, net of tax			16,040	11,853
Balances, end of period	(732,760)	(775,960)	(732,760)	(775,960)
Foreign currency adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(44,564)	(150,955)
Other comprehensive income (loss) before reclassifications			(29,073)	66,706
Reclassifications into earnings			0	0
Other comprehensive (loss) income, net of tax			(29,073)	66,706
Balances, end of period	(73,637)	(84,249)	(73,637)	(84,249)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(792,173)	(940,133)
Other comprehensive (loss) income, net of tax			(18,078)	80,818
Balances, end of period	$ (810,251)	$ (859,315)	$ (810,251)	$ (859,315)

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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