CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ (7,400)	$ 19,890
Adjustments to reconcile net income (loss) to net cash (used in)/provided by operating activities:
Premium amortization and (discount accretion), net	(1,710)	(1,506)
Accretion of deferred commitment fees	(1,233)	(406)
Amortization of deferred financing costs	5,684	1,106
Share-based compensation	39	39
Realized (gain)/loss on sale of real estate securities	438	0
Unrealized (gain)/loss on commercial mortgage loans held-for-sale	1,934	336
Unrealized (gain)/loss on derivative instruments	4,836	1,066
Unrealized (gain)/loss on other real estate investments	61	0
Depreciation and amortization	588	0
Recognition of deferred rent revenue	(89)	0
Loan loss (recovery)/provision	14,597	2,495
Impairment losses on real estate owned assets	398	0
Origination of commercial mortgage loans, held-for-sale	(119,349)	(202,950)
Proceeds from sale of commercial mortgage loans, held-for-sale	138,164	177,138
Changes in assets and liabilities:
Accrued interest receivable	1,664	(437)
Prepaid expenses and other assets	(6,300)	(1,845)
Accounts payable and accrued expenses	(2,068)	772
Due to affiliates	9,249	94
Interest payable	(2,072)	458
Net cash (used in)/provided by operating activities	37,431	(3,750)
Cash flows from investing activities:
Origination and purchase of commercial mortgage loans, held for investment	(287,644)	(310,904)
Principal repayments received on commercial mortgage loans, held for investment	426,742	235,633
Purchase of other real estate investments	(624)	0
Purchase of real estate securities	(134,818)	(40,200)
Principal repayments received on real estate securities	643	57
Purchase of derivative instruments	(689)	(522)
Net cash (used in)/provided by investing activities	3,610	(115,936)
Cash flows from financing activities:
Proceeds from issuances of common stock	10,726	19,409
Proceeds from issuances of redeemable convertible preferred stock	70	14,979
Common stock repurchases	(6,716)	(7,207)
Repayments of collateralized loan obligation	(68,894)	(200,426)
Borrowings on repurchase agreements - commercial mortgage loans	65,413	490,189
Repayments of repurchase agreements - commercial mortgage loans	(83,432)	(268,740)
Borrowings on repurchase agreements - real estate securities	340,116	167,587
Repayments of repurchase agreements - real estate securities	(237,596)	(190,048)
Borrowing on other financing and loan participation - commercial mortgage loans	15,190	0
Borrowings on Mortgage Note Payable	11,000	0
Payments of deferred financing costs	(75)	0
Distributions paid	(16,776)	(13,791)
Net cash (used in)/provided by financing activities:	29,026	11,952
Net change in cash, cash equivalents and restricted cash	70,067	(107,734)
Cash, cash equivalents and restricted cash, beginning of period	109,122	204,419	$ 204,419
Cash, cash equivalents and restricted cash, end of period	179,189	96,685	109,122
Supplemental disclosures of cash flow information:
Taxes paid	0	0
Interest paid	20,880	18,802
Supplemental disclosures of non-cash flow information:
Distributions payable				$ 6,956	$ 6,912	$ 6,100
Common stock issued through distribution reinvestment plan	3,548	3,392
Commercial mortgage loans transferred from held for investment to held for sale	9,619	0
Real estate owned received in foreclosure	14,000	0
Cash and cash equivalents				88,960	87,246	79,698
Restricted cash				90,229	21,876	16,987
Cash, cash equivalents and restricted cash, end of period	$ 179,189	$ 96,685	$ 109,122	$ 179,189	$ 109,122	$ 96,685