Non-operating (loss) income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Non-operating (loss) income, net [Abstract]
Interest Income	$ 805	$ 6,457	$ 7,500	$ 21,045
income from transition services	0	3,750	2,100	11,850
Gain (Loss) on Disposition of Business	(9)	64	5,602	817
Other Nonoperating Income (Expense)	(21)	227	60	425
Nonoperating (loss) Income	$ 775	$ 10,498	$ 15,262	$ 34,137