USE OF SPECIAL PURPOSE ENTITIES AND VARIABLE INTEREST ENTITIES - Summary of Loan and Borrowing Characteristics (Details)		3 Months Ended	6 Months Ended	12 Months Ended
		Mar. 31, 2023 USD ($) mortgageLoan contract instrument	Jun. 30, 2022 instrument contract	Dec. 31, 2022 USD ($) mortgageLoan
Variable Interest Entity [Line Items]
Collateralized loan obligations	[1]	$ 829,933,826		$ 829,310,498
One month LIBOR rate (as a percent)		4.70%		4.18%
One month SOFR rate ( as a percent)		4.70%		4.19%
Weighted average LIBOR floor rate (as a percent)		0.27%		0.25%
SOFR spread rate (as a percent)		3.42%		3.41%
Basis spread on one-month LIBOR (percent)		1.43%		1.43%
London Interbank Offered Rate (LIBOR)
Variable Interest Entity [Line Items]
One month LIBOR rate (as a percent)		4.68%		4.32%
Financing receivable, floating Rate (as a percent)		75.80%		80.50%
Secured​ Overnight ​Financing​ Rate
Variable Interest Entity [Line Items]
Financing receivable, floating Rate (as a percent)		24.20%		19.50%
Commercial Real Estate Portfolio Segment
Variable Interest Entity [Line Items]
Collateral (loan investments) (Count) | mortgageLoan		67		71
Carrying Value		$ 1,019,821,199		$ 1,076,148,186
Financing receivable, floating Rate (as a percent)		100.00%		100.00%
LFT CRE 2021-FL1, Ltd.
Variable Interest Entity [Line Items]
Financings provided, (Count) | instrument		1	1
Collateralized loan obligations		$ 829,933,826		$ 829,310,498
LFT CRE 2021-FL1, Ltd. | London Interbank Offered Rate (LIBOR)
Variable Interest Entity [Line Items]
Weighted average yield (percent)		8.12%	7.60%
Weighted average yield (percent)		6.12%	5.75%
LFT CRE 2021-FL1, Ltd. | Commercial Real Estate Portfolio Segment
Variable Interest Entity [Line Items]
Collateral (loan investments) (Count) | contract		65	64
Principal Value | LFT CRE 2021-FL1, Ltd.
Variable Interest Entity [Line Items]
Carrying Value		$ 997,565,052		996,492,150
Collateralized loan obligations		833,750,000		833,750,000
Carrying Value | LFT CRE 2021-FL1, Ltd.
Variable Interest Entity [Line Items]
Carrying Value		994,280,018		996,511,403
Collateralized loan obligations		829,933,826		829,310,498
Debt issuance costs		$ 3,816,174		$ 4,439,502

[1] Our consolidated balance sheets include assets and liabilities of consolidated variable interest entities ("VIEs") as the Company was the primary beneficiary of these VIEs. As of March 31, 2023 and December 31, 2022, assets of consolidated VIEs totaled $1,002,563,861 and $1,005,507,371, respectively and the liabilities of consolidated VIEs totaled $832,342,571 and $831,575,144 respectively. See Note 4 for further discussion.