Accumulated Other Comprehensive Loss (AOCL) (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 29,430	$ 86,450	$ 286,096	$ 101,842
Other comprehensive income (loss) before reclassifications			(13,696)	27,348
Reclassifications into earnings			17,577	13,935
Other comprehensive income, net of tax	21,612	10,300	3,881	41,283
Balances, end of period	44,580	52,972	44,580	52,972
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period			337	191
Other comprehensive income (loss) before reclassifications			(1,416)	18
Reclassifications into earnings			(29)	(89)
Other comprehensive income, net of tax			(1,445)	(71)
Balances, end of period	(1,108)	120	(1,108)	120
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			5,356	5,952
Reclassifications into earnings			(2,641)	77
Other comprehensive income, net of tax			2,715	6,029
Balances, end of period	5,564	2,968	5,564	2,968
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			20,247	13,947
Other comprehensive income, net of tax			20,247	13,947
Balances, end of period	(798,771)	(832,514)	(798,771)	(832,514)
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			(17,636)	21,378
Reclassifications into earnings			0	0
Other comprehensive income, net of tax			(17,636)	21,378
Balances, end of period	(41,947)	(78,252)	(41,947)	(78,252)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(857,874)	(917,978)	(840,143)	(948,961)
Other comprehensive income, net of tax	21,612	10,300	3,881	41,283
Balances, end of period	$ (836,262)	$ (907,678)	$ (836,262)	$ (907,678)

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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