Basis of Presentation (Additional Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Non-cash operating items:
Equity in net (income) loss of affiliates	$ 117,074	$ (42,004)
Deferred taxes	1,569	1,464
Depreciation and amortization	1	6
Right-of-use asset, net of lease liability	(1)	4
Amortization of prior service credit and actuarial (gain) loss	302	230
Net non-cash operating items	118,945	(40,300)
Supplemental information:
Interest paid	5	5
Income tax refunds	178	2,980
Income tax payments	$ 63	$ 101