Basis of Presentation (Additional Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Non-cash operating items:
Equity in net (income) loss of affiliates	$ (76,515)	$ (41,278)	$ 40,559	$ (83,282)
Deferred taxes			(300)	3,308
Depreciation and amortization			2	8
Right-of-use asset, net of lease liability			(3)	16
Amortization of prior service credit and actuarial (gain) loss			642	501
Net non-cash operating items			40,900	(79,449)
Supplemental information:
Interest paid			11	10
Income tax refunds			178	2,980
Income tax payments			$ 126	$ 163