Accumulated Other Comprehensive Loss (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 19,163	$ 29,430	$ 66,395	$ 286,096
Other comprehensive income (loss) before reclassifications			(12,076)	(13,696)
Reclassifications into earnings			19,904	17,577
Other comprehensive income, net of tax	16,235	21,612	7,828	3,881
Balances, end of period	53,370	44,580	53,370	44,580
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			(1,411)	337
Other comprehensive income (loss) before reclassifications			3,456	(1,416)
Reclassifications into earnings			(32)	(29)
Other comprehensive income, net of tax			3,424	(1,445)
Balances, end of period	2,013	(1,108)	2,013	(1,108)
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			(4,783)	5,356
Reclassifications into earnings			(194)	(2,641)
Other comprehensive income, net of tax			(4,977)	2,715
Balances, end of period	(4,575)	5,564	(4,575)	5,564
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			20,130	20,247
Other comprehensive income, net of tax			20,130	20,247
Balances, end of period	(830,933)	(798,771)	(830,933)	(798,771)
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			(10,749)	(17,636)
Reclassifications into earnings			0	0
Other comprehensive income, net of tax			(10,749)	(17,636)
Balances, end of period	2,192	(41,947)	2,192	(41,947)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(847,538)	(857,874)	(839,131)	(840,143)
Other comprehensive income, net of tax	16,235	21,612	7,828	3,881
Balances, end of period	$ (831,303)	$ (836,262)	$ (831,303)	$ (836,262)

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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