Accumulated Other Comprehensive Loss (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 286,096	$ 101,842
Other comprehensive income (loss) before reclassifications	(26,334)	24,425
Reclassifications into earnings	8,603	6,558
Other comprehensive (loss) income, net of tax	(17,731)	30,983
Balances, end of period	29,430	86,450
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	337	191
Other comprehensive income (loss) before reclassifications	(120)	258
Reclassifications into earnings	(54)	(95)
Other comprehensive (loss) income, net of tax	(174)	163
Balances, end of period	163	354
Available for sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	2,849	(3,061)
Other comprehensive income (loss) before reclassifications	1,521	2,799
Reclassifications into earnings	(213)	17
Other comprehensive (loss) income, net of tax	1,308	2,816
Balances, end of period	4,157	(245)
Pension and postretirement benefit plans
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(819,018)	(846,461)
Other comprehensive income (loss) before reclassifications	0	0
Reclassifications into earnings	8,870	6,636
Other comprehensive (loss) income, net of tax	8,870	6,636
Balances, end of period	(810,148)	(839,825)
Foreign currency adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(24,311)	(99,630)
Other comprehensive income (loss) before reclassifications	(27,735)	21,368
Reclassifications into earnings	0	0
Other comprehensive (loss) income, net of tax	(27,735)	21,368
Balances, end of period	(52,046)	(78,262)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(840,143)	(948,961)
Other comprehensive (loss) income, net of tax	(17,731)	30,983
Balances, end of period	$ (857,874)	$ (917,978)

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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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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