Accumulated Other Comprehensive Income (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 86,356	$ 62,914	$ 101,842	$ 30,553
Other comprehensive income (loss) before reclassifications			27,348	(33,524)
Reclassifications into earnings			13,935	16,660
Other comprehensive income (loss), net of tax	10,394	(36,614)	41,283	(16,864)
Balances, end of period	52,972	48,961	52,972	48,961
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			191	(406)
Other comprehensive income (loss) before reclassifications			18	(511)
Reclassifications into earnings			(89)	762
Other comprehensive income (loss), net of tax			(71)	251
Balances, end of period	120	(155)	120	(155)
Available for sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(3,061)	1,597
Other comprehensive income (loss) before reclassifications			5,952	(5,154)
Reclassifications into earnings			77	(142)
Other comprehensive income (loss), net of tax			6,029	(5,296)
Balances, end of period	2,968	(3,699)	2,968	(3,699)
Pension and postretirement benefit plans
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(846,461)	(748,800)
Other comprehensive income (loss) before reclassifications			0	0
Reclassifications into earnings			13,947	16,040
Other comprehensive income (loss), net of tax			13,947	16,040
Balances, end of period	(832,514)	(732,760)	(832,514)	(732,760)
Foreign currency adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(99,630)	(47,331)
Other comprehensive income (loss) before reclassifications			21,378	(27,859)
Reclassifications into earnings			0	0
Other comprehensive income (loss), net of tax			21,378	(27,859)
Balances, end of period	(78,252)	(75,190)	(78,252)	(75,190)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(918,072)	(775,190)	(948,961)	(794,940)
Other comprehensive income (loss), net of tax	10,394	(36,614)	41,283	(16,864)
Balances, end of period	$ (907,678)	$ (811,804)	$ (907,678)	$ (811,804)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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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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