SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional information (Details) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended		12 Months Ended
	Jan. 19, 2022 USD ($)	Dec. 31, 2021 USD ($) $ / shares shares	Jun. 30, 2018	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($) $ / shares shares	Mar. 31, 2022 EUR (€)	Dec. 31, 2021 EUR (€)	Dec. 20, 2021 USD ($)	Dec. 01, 2021	Nov. 30, 2021
Accounting Policies [Line Items]
Interest expense from loan participations				$ 0	$ 468
Advertising costs				1,763	578
Market value percentage			85.00%
Recognized compensation expense				153	227
Restricted cash		$ 927		928		$ 927
Depreciation and amortization				1,032	873
Net of unamortized costs, origination fees, premiums and discounts		9,304		8,170		9,304
Unrealized gains (losses)				10,937	10,726
Partnership investment interests				74,222		77,383
Investment securities		59,745		73,006		59,745
Fair value adjustment of warrants				4,879
Fair value assets		2,613,177		2,397,321		2,613,177
Senior notes payable		1,606,560		1,627,649		1,606,560
Fair value		1,661,189		1,626,938		1,661,189
Forward exchange contracts | €							€ 0	€ 6,000,000
Transaction gains				296	555
Warrant liability		12,938		8,059		12,938
Redemption value		345,000		345,000		345,000
Deemed dividend				18,182
Offering costs incurred				7,716
Public warrants amount				10,466
Equity investments		$ 39,190		45,978		$ 39,190
Equity securities					64,754
Loan receivable amount					35,000
Cash funded					35,000
Agent fees				12,051	11,360
Sold price per unit (in dollars per share) | $ / shares		$ 10.00				$ 10.00
Assets held in trust		$ 345,000				$ 345,000
FocalPoint Securities, LLC ("FocalPoint")
Accounting Policies [Line Items]
Business combination, consideration transferred, equity	$ 20,320			20,320
Business combination, deferred cash consideration				22,661
W.S. Badcock Corporation
Accounting Policies [Line Items]
Cash									$ 400,000
Loans and leases receivable, allowance		400,000		380,591		400,000
Fixed Income Securities
Accounting Policies [Line Items]
Interest expense				11,766	18,721
Forward Contracts
Accounting Policies [Line Items]
Net gain (loss) forward exchange contract				68	$ 310
BRPM 150
Accounting Policies [Line Items]
Gross proceeds						172,500
BRPM 250
Accounting Policies [Line Items]
Gross proceeds						172,500
Warrant
Accounting Policies [Line Items]
Warrant liability		$ 12,938		8,059		$ 12,938
IPO
Accounting Policies [Line Items]
Consummated units (in shares) | shares						17,250,000
Common Class A
Accounting Policies [Line Items]
Exercise price per share (in dollars per share) | $ / shares		$ 11.50				$ 11.50
Fair Value, Measurements, Recurring
Accounting Policies [Line Items]
Loans receivable carrying value		$ 877,527		875,794		$ 877,527
Loans receivable		$ 886,831		$ 883,965		886,831
Great American Global Partners, LLC
Accounting Policies [Line Items]
Ownership, percentage				50.00%			50.00%
Bebe Stores Inc. ("bebe")
Accounting Policies [Line Items]
Ownership, percentage				40.10%			40.10%			40.10%	39.50%
Additional purchase of shares (in shares) | shares		71,970
Additional purchase of value		$ 612
Lingo
Accounting Policies [Line Items]
Rate of equity interests				40.00%			40.00%
Minimum
Accounting Policies [Line Items]
Cash fee percentage				7.00%
Carried interest percentage				8.00%
Maximum
Accounting Policies [Line Items]
Cash fee percentage				10.00%
Carried interest percentage				15.00%
Significant unobservable inputs (Level 3)
Accounting Policies [Line Items]
Fair value assets		1,250,735		$ 1,271,055		1,250,735
Warrant liability		$ 0		$ 0		$ 0
Significant unobservable inputs (Level 3) | Fair Value, Measurements, Recurring
Accounting Policies [Line Items]
Percentage of total assets measured in Level 3 of the hierarchy level		21.40%		24.20%		21.40%	24.20%	21.40%
Loans Receivable
Accounting Policies [Line Items]
Loans receivable fair value				$ 882,391		$ 873,186