Accumulated Other Comprehensive Income (Loss) (Schedule of Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Accumulated Other Comprehensive Income (Loss)
Interest expense	$ (5,138)	$ (2,941)	$ (12,185)	$ (7,069)
Net loss resulting from early retirement of debt	9,629		13,749
Pension settlement	414	988	414	988
Interest and investment income	528	147	552	474
Provision for (benefit from) income taxes	(496)	(2,006)	(951)	(2,383)
Net income (loss)	407,563	27,866	679,435	21,824
Reclassification out of Accumulated Other Comprehensive Income | Derivative instruments
Accumulated Other Comprehensive Income (Loss)
Interest expense		(632)	(112)	(1,256)
Net loss resulting from early retirement of debt			(1,428)
Provision for (benefit from) income taxes	0	0	0	0
Net income (loss)		(632)	(1,540)	(1,256)
Reclassification out of Accumulated Other Comprehensive Income | Pension, postretirement and other post-employment benefits
Accumulated Other Comprehensive Income (Loss)
Amortization of actuarial gains (losses), net	346	(590)	973	(1,181)
Amortization of prior service credits	177	43	73	87
Provision for (benefit from) income taxes	0	0	0	0
Net income (loss)	937	441	1,460	(106)
Reclassification out of Accumulated Other Comprehensive Income | Available-for-sale securities
Accumulated Other Comprehensive Income (Loss)
Interest and investment income		14	(182)	24
Provision for (benefit from) income taxes	$ 0	0	0	0
Net income (loss)		$ 14	$ (182)	$ 24