Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Schedule Of Income Taxes [Line Items]
Effective income tax rate	21.00%	21.00%
Net foreign operating loss carry-forward	$ 65,900
Valuation allowance recognized	63,239	$ 54,610
Net change in valuation allowance	8,600	(4,000)
Federal net operating loss carry-forward	770,800
Net state operating tax loss carry-forward	412,000
Deferred foreign withholding taxes	9,796	$ 7,706
Income inclusion for GILTI	10,000
Real Estate Investment Trust [Member]
Schedule Of Income Taxes [Line Items]
Federal net operating loss carry-forward	651,100
Expire Between 2025 and 2037 [Member]
Schedule Of Income Taxes [Line Items]
Federal net operating loss carry-forward	745,200
Indefinite Carry-forward [Member]
Schedule Of Income Taxes [Line Items]
Federal net operating loss carry-forward	$ 25,600
Minimum [Member]
Schedule Of Income Taxes [Line Items]
Operating loss carry-forward, expiration year	2025
Foreign and state operating tax loss carry forwards expiration date	2021
Maximum [Member]
Schedule Of Income Taxes [Line Items]
Operating loss carry-forward, expiration year	2037

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Schedule Of Income Taxes [Line Items]

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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Amount of income tax expense from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act.

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