Income Taxes and Distributions (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Textuals [Line Items]
Income tax provision (benefit)	$ 9,968	$ 2,957	$ 8,674
Tax valuation allowance	244,938	159,057	155,592	$ 127,283
NOL carryforwards	351,254
International
Income Tax Textuals [Line Items]
Income tax provision (benefit)	5,777	(3,892)	$ 9,804
Canada
Income Tax Textuals [Line Items]
NOL carryforwards	262,345	195,791
United Kingdom
Income Tax Textuals [Line Items]
NOL carryforwards	$ 207,085	$ 209,776