Loans Receivable (Summary of Net Loans Receivable) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for losses on real estate loans receivable	$ (42,376)	$ (68,372)
Real estate loans receivable, net of allowance	270,382	330,339
Non real estate loans	362,850	282,443
Allowance for losses on non real estate loans receivable	(25,996)	0
Non real estate loans receivable, net of allowance	336,854	282,443
Total loans receivable, net of allowance	607,236	612,782
Mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate loans receivable, gross	188,062	317,443
Other real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate loans receivable, gross	$ 124,696	$ 81,268

Amount, after allowance for credit loss, of accounts and financing receivable. Includes, but is not limited to, notes and loan receivable.

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