Loans Held-for-Investment (Details) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($) loan	Sep. 30, 2019	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	$ 4,072,788			$ 4,257,145
Unamortized (discount) premium	(72)			(124)
Unamortized net deferred origination fees	(20,515)			(30,809)
Allowance for credit losses	(73,339)		$ (76,710)	(16,692)
Carrying value	3,978,862			4,226,212
Unfunded commitments	$ 596,440			$ 748,878
Number of loans \| loan	110			120
Weighted average coupon	5.10%			5.40%
Weighted average years to maturity	1 year 3 months 18 days	1 year 9 months 18 days
First Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	$ 4,045,912			$ 4,229,194
Unamortized (discount) premium	(72)			(124)
Unamortized net deferred origination fees	(20,543)			(30,788)
Allowance for credit losses	(71,632)
Carrying value	3,953,665			4,198,282
Unfunded commitments	$ 596,440			$ 748,878
Number of loans \| loan	107			117
Weighted average coupon	5.10%			5.40%
Weighted average years to maturity	1 year 3 months 18 days	1 year 9 months 18 days
Second Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	$ 12,586			$ 13,503
Unamortized (discount) premium	0			0
Unamortized net deferred origination fees	28			(21)
Allowance for credit losses	(1,421)
Carrying value	11,193			13,482
Unfunded commitments	$ 0			$ 0
Number of loans \| loan	2			2
Weighted average coupon	10.40%			11.70%
Weighted average years to maturity	1 year 2 months 12 days	2 years
Junior Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	$ 14,290			$ 14,448
Unamortized (discount) premium	0			0
Unamortized net deferred origination fees	0			0
Allowance for credit losses	(286)
Carrying value	14,004			14,448
Unfunded commitments	$ 0			$ 0
Number of loans \| loan	1			1
Weighted average coupon	8.00%			8.00%
Weighted average years to maturity	6 years 3 months 18 days	7 years 1 month 6 days

Number of loans held-for-investment as of period-end.

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- Definition

Reflects the cumulative amount of premiums over or discounts from face amounts of loans held-for-investment that are being amortized into income as an adjustment to yield.

+ References

No definition available.

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- Definition

Reflects the cumulative amount of unamortized costs incurred to originate loans held-for-investment that are deferred and are being amortized into income as an adjustment to yield.

+ References

No definition available.

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- Definition

The amount of unfunded commitments for which the entity is obligated, to loans held-for-investment.

+ References

No definition available.

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- Definition

Weighted average coupon rate of all loans held-for-investment as of period-end.

+ References

No definition available.

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Weighted average years to maturity of all loans held-for-investment as of period-end.

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

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.

+ References

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