Basis of Presentation (Additional Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Non-cash operating items:
Equity in net (income) loss of affiliates	$ (34,602)	$ 117,074
Deferred taxes	(562)	1,569
Depreciation	1	1
Right-of-use asset, net of lease liability	(3)	(1)
Amortization of prior service credit and actuarial (gain) loss	399	302
Net non-cash operating items - continuing operations	(34,767)	118,945
Supplemental information:
Interest paid - continuing operations	6	5
Income tax refunds	2	178
Income tax payments	$ 63	$ 63