Accumulated Other Comprehensive Income (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 52,972	$ 48,961	$ 101,842	$ 30,553
Other comprehensive income (loss) before reclassifications			1,098	(37,329)
Reclassifications into earnings			21,411	26,104
Other comprehensive (loss) income, net of tax	(18,774)	5,639	22,509	(11,225)
Balances, end of period	25,412	108,031	25,412	108,031
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			191	(406)
Other comprehensive income (loss) before reclassifications			135	(593)
Reclassifications into earnings			(57)	1,366
Other comprehensive (loss) income, net of tax			78	773
Balances, end of period	269	367	269	367
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			7,547	(6,402)
Reclassifications into earnings			(31)	(112)
Other comprehensive (loss) income, net of tax			7,516	(6,514)
Balances, end of period	4,455	(4,917)	4,455	(4,917)
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			21,499	24,850
Other comprehensive (loss) income, net of tax			21,499	24,850
Balances, end of period	(824,962)	(723,950)	(824,962)	(723,950)
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			(6,584)	(30,334)
Reclassifications into earnings			0	0
Other comprehensive (loss) income, net of tax			(6,584)	(30,334)
Balances, end of period	(106,214)	(77,665)	(106,214)	(77,665)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(907,678)	(811,804)	(948,961)	(794,940)
Other comprehensive (loss) income, net of tax	(18,774)	5,639	22,509	(11,225)
Balances, end of period	$ (926,452)	$ (806,165)	$ (926,452)	$ (806,165)

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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