Loans Receivable and Other Lending Investments, net (Schedule of Loans Receivable) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other lending investments	$ 162,538	$ 153,216
Total gross carrying value of loans receivable and other lending investments	745,500	856,495
Allowance for loan losses	(13,170)	(28,634)
Total loans receivable and other lending investments, net	732,330	827,861
Financing receivables (refer to Note 5)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other lending investments	46,549	44,339
Held-to-maturity debt securities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other lending investments	90,715	84,981
Available-for-sale debt securities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other lending investments	25,274	23,896
Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	582,962	703,280
Construction loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	514,833	614,386
Allowance for loan losses	(6,541)	(6,668)
Construction loans \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	514,833	614,386
Construction loans \| Commercial Portfolio Segment \| Senior mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	449,733	518,992
Construction loans \| Commercial Portfolio Segment \| Corporate/Partnership loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	65,100	95,394
Completed construction \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	$ 241,800
Percentage of construction loans	47.00%
Substantially completed construction \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	$ 24,600
Percentage of construction loans	5.00%
Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	$ 68,129	88,893
Allowance for loan losses	(1,643)	(265)
Loans \| Commercial Portfolio Segment \| Senior mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	35,922	53,592
Loans \| Commercial Portfolio Segment \| Corporate/Partnership loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	20,567	24,424
Loans \| Commercial Portfolio Segment \| Subordinate mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subtotal - gross carrying value of loans	$ 11,640	$ 10,877

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