Loans Receivable (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accrued interest	$ 15,615	$ 6,897,000
Non-real estate loans	455,508	362,850
Allowance for credit loss	215,239	25,996
Provision for loan losses	94,436	$ 18,690	$ 0
Non-real estate loans receivable
Financing Receivable, Troubled Debt Restructuring [Line Items]
Non-real estate loans	86,411
Allowance for credit loss	42,376
Provision for loan losses	88,201
Real estate loan receivable
Financing Receivable, Troubled Debt Restructuring [Line Items]
Provision for loan losses	$ 224,036

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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