Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	$ 1,722,785	$ 1,803,999	$ 1,773,949
Other comprehensive (loss) income, before reclassifications	139,595	146,462	105,777
Income tax benefit (expense)	(41,061)	(28,005)	(23,124)
Total other comprehensive income before reclassifications, net of tax	98,534	118,457	82,653
Reclassifications	186,188	(82,555)	13,288
Income tax expense	(42,224)	17,630	(3,206)
Total reclassification from other comprehensive income, net of tax	143,964	(64,925)	10,082
Total other comprehensive loss, net of tax	242,498	53,532	92,735
Balance, end of period	2,553,244	1,722,785	1,803,999
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(483,417)	(536,949)	(629,684)
Total other comprehensive loss, net of tax	242,498	53,532	92,735
Balance, end of period	(240,919)	(483,417)	(536,949)
Foreign currency translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(7,589)	(40,813)	(49,608)
Other comprehensive (loss) income, before reclassifications	(38,988)	37,088	9,229
Income tax benefit (expense)	2,176	(3,864)	(434)
Total other comprehensive income before reclassifications, net of tax	(36,812)	33,224	8,795
Reclassifications	0	0	0
Income tax expense	0	0	0
Total reclassification from other comprehensive income, net of tax	0	0	0
Total other comprehensive loss, net of tax	(36,812)	33,224	8,795
Balance, end of period	(44,401)	(7,589)	(40,813)
Derivative financial instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(46,116)	(14,586)	1,785
Other comprehensive (loss) income, before reclassifications	(73,207)	107,181	6,477
Income tax benefit (expense)	15,883	(23,626)	(1,541)
Total other comprehensive income before reclassifications, net of tax	(57,324)	83,555	4,936
Reclassifications	130,609	(148,107)	(27,732)
Income tax expense	(29,174)	33,022	6,425
Total reclassification from other comprehensive income, net of tax	101,435	(115,085)	(21,307)
Total other comprehensive loss, net of tax	44,111	(31,530)	(16,371)
Balance, end of period	(2,005)	(46,116)	(14,586)
Pension and postretirement benefit plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning of period	(429,712)	(481,550)	(581,861)
Other comprehensive (loss) income, before reclassifications	251,790	2,193	90,071
Income tax benefit (expense)	(59,120)	(515)	(21,149)
Total other comprehensive income before reclassifications, net of tax	192,670	1,678	68,922
Reclassifications	55,579	65,552	41,020
Income tax expense	(13,050)	(15,392)	(9,631)
Total reclassification from other comprehensive income, net of tax	42,529	50,160	31,389
Total other comprehensive loss, net of tax	235,199	51,838	100,311
Balance, end of period	(194,513)	(429,712)	(481,550)
Pension and postretirement benefit plans; Prior service credits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications	(3,570)	(3,469)	(4,311)
Pension and postretirement benefit plans; Actuarial losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications	68,989	65,981	44,788
Pension and postretirement benefit plans; Curtailment and settlement losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications	$ (9,840)	$ 3,040	$ 543