Accumulated Other Comprehensive Income (Changes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	$ 101,842	$ 35,166
Other comprehensive income (loss) before reclassifications	24,331	11,244
Reclassifications into earnings	6,558	8,633
Other comprehensive income, net of tax	30,889	19,877
Balances, end of period	86,356	67,654
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	191	(406)
Other comprehensive income (loss) before reclassifications	258	43
Reclassifications into earnings	(95)	443
Other comprehensive income, net of tax	163	486
Balances, end of period	354	80
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	2,799	(4,010)
Reclassifications into earnings	17	18
Other comprehensive income, net of tax	2,816	(3,992)
Balances, end of period	(245)	(2,395)
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	6,636	8,172
Other comprehensive income, net of tax	6,636	8,172
Balances, end of period	(839,825)	(740,628)
Foreign currency adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(99,630)	(46,869)
Other comprehensive income (loss) before reclassifications	21,274	15,211
Reclassifications into earnings	0	0
Other comprehensive income, net of tax	21,274	15,211
Balances, end of period	(78,356)	(31,658)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balances, beginning of period	(948,961)	(794,478)
Other comprehensive income, net of tax	30,889	19,877
Balances, end of period	$ (918,072)	$ (774,601)

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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