Loans Receivable - Schedule of Loans Receivable (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Unamortized discounts, fees, and costs	$ 887	$ 863
Reserve for loan losses	(11,547)	0
Loans receivable including loans receivable held for sale	253,785	190,579
Loans receivable held for sale	(22,623)	0
Loans receivable, net	231,162	190,579
Remaining loans receivable commitments	14,000	25,000
Loans receivable commitments	196,000	174,000
Secured mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	212,393	161,964
Loans receivable held for sale	(11,000)
Mezzanine and other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, gross	52,052	$ 27,752
Loans receivable held for sale	$ (12,000)

Loans and Leases Receivable, Remaining Commitments

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of unamortized loan commitment, origination, and other fees (costs) and purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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Amount, before allowance for credit loss, of financing receivable.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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