Non-operating income, net Non-Operating income, net (Components of Non-operating income, net) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Non-operating (loss) income, net [Abstract]
Investment Income, Interest and Dividend	$ 7,815	$ 26,596	$ 26,490
income from transition services	2,100	15,600	1,132
Gain (Loss) on Disposition of Business	6,402	817	54,840
Loss on Extinguishment of Debt	0	0	6,554
Other Nonoperating Income (Expense)	(130)	247	1,061
Nonoperating Income (Expense)	$ 16,187	$ 43,260	$ 76,969