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Income Taxes and Distributions (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Textuals [Line Items]
Income tax provision (benefit)	$ 2,957	$ 8,674	$ 20,128
Tax valuation allowance	159,057	155,592	127,283	$ 96,838
NOL carryforwards	337,287
International
Income Tax Textuals [Line Items]
Income tax provision (benefit)	(3,892)	9,804,000	$ 4,806,000
Canada
Income Tax Textuals [Line Items]
NOL carryforwards	195,791,000	154,029,000
United Kingdom
Income Tax Textuals [Line Items]
NOL carryforwards	$ 209,776,000	$ 242,377,000