Basis of Presentation (Additional Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Non-cash operating items:
Equity in net (income) loss of affiliates	$ (49,645)	$ (8,784)	$ (9,086)	$ (92,066)
Deferred taxes			(253)	2,802
Depreciation and amortization			3	9
Right-of-use asset, net of lease liability			(4)	12
Recovery of affiliate doubtful receivable			(5,854)	0
Amortization of prior service credit and actuarial (gain) loss			963	752
Net non-cash operating items			(14,231)	(88,491)
Supplemental information:
Interest paid			20	15
Income tax refunds			178	2,980
Income tax payments			$ 190	$ 226