Accumulated Other Comprehensive Loss (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 66,395	$ 286,096
Other comprehensive income (loss) before reclassifications	(18,262)	(26,334)
Reclassifications into earnings	9,855	8,603
Other comprehensive loss, net of tax	(8,407)	(17,731)
Balances, end of period	19,163	29,430
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(1,411)	337
Other comprehensive income (loss) before reclassifications	4,881	(120)
Reclassifications into earnings	(51)	(54)
Other comprehensive loss, net of tax	4,830	(174)
Balances, end of period	3,419	163
Available for sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	402	2,849
Other comprehensive income (loss) before reclassifications	(8,885)	1,521
Reclassifications into earnings	(31)	(213)
Other comprehensive loss, net of tax	(8,916)	1,308
Balances, end of period	(8,514)	4,157
Pension and postretirement benefit plans
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(851,063)	(819,018)
Other comprehensive income (loss) before reclassifications	0	0
Reclassifications into earnings	9,937	8,870
Other comprehensive loss, net of tax	9,937	8,870
Balances, end of period	(841,126)	(810,148)
Foreign currency adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	12,941	(24,311)
Other comprehensive income (loss) before reclassifications	(14,258)	(27,735)
Reclassifications into earnings	0	0
Other comprehensive loss, net of tax	(14,258)	(27,735)
Balances, end of period	(1,317)	(52,046)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(839,131)	(840,143)
Other comprehensive loss, net of tax	(8,407)	(17,731)
Balances, end of period	$ (847,538)	$ (857,874)

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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