BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Reclassifications (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Consolidated Statements of Cash Flows
Depreciation and amortization, net	$ 15,211	$ 15,461
Deferred rent and amortization of intangible assets, liabilities and lease inducements		0
Other assets	(1,983)	413
Payment of revolving credit facilities, mortgages payable, term notes and principal on SBA 7(a) loan-backed notes	(132,759)	(55,159)
Payment of principal on SBA 7(a) loan-backed notes		0
Payment of unsecured revolving lines of credit, revolving credit facility and or term note		0
Proceeds from revolving credit facilities and term notes	30,396	77,516
Proceeds from unsecured revolving lines of credit, revolving credit facility and or term note		0
Borrowed funds from the Federal Reserve through the Paycheck Protection Program Liquidity Facility		0
Payment of deferred costs	(2)	(740)
Payment of deferred loan costs		0
Net proceeds from issuance of Preferred Stock	20,899	32,912
Additions to deferred loan costs included in accounts payable and accrued expenses		0
Accrued deferred costs	0	361
Preferred stock offering costs offset against redeemable preferred stock	296	455
Preferred stock offering costs offset against redeemable preferred stock in permanent equity		0
Accrued redeemable preferred stock fees	677	392
Equity-based payment for management fees	$ 4,652	5,022
Payment of management fees and base service fee in preferred stock		0
Series D Preferred Stock
Consolidated Statements of Cash Flows
Net proceeds from issuance of Preferred Stock		0
Accrued redeemable preferred stock fees		0
As previously reported
Consolidated Statements of Cash Flows
Depreciation and amortization, net		15,728
Deferred rent and amortization of intangible assets, liabilities and lease inducements		(1,013)
Other assets		1,159
Payment of revolving credit facilities, mortgages payable, term notes and principal on SBA 7(a) loan-backed notes		0
Payment of principal on SBA 7(a) loan-backed notes		(7,159)
Payment of unsecured revolving lines of credit, revolving credit facility and or term note		(48,000)
Proceeds from revolving credit facilities and term notes		0
Proceeds from unsecured revolving lines of credit, revolving credit facility and or term note		61,500
Borrowed funds from the Federal Reserve through the Paycheck Protection Program Liquidity Facility		16,016
Payment of deferred costs		(205)
Payment of deferred loan costs		(535)
Net proceeds from issuance of Preferred Stock		32,466
Additions to deferred loan costs included in accounts payable and accrued expenses		221
Accrued deferred costs		140
Preferred stock offering costs offset against redeemable preferred stock		451
Preferred stock offering costs offset against redeemable preferred stock in permanent equity		4
Accrued redeemable preferred stock fees		386
Equity-based payment for management fees		2,359
Payment of management fees and base service fee in preferred stock		2,663
As previously reported | Series D Preferred Stock
Consolidated Statements of Cash Flows
Net proceeds from issuance of Preferred Stock		446
Accrued redeemable preferred stock fees		6
Reclassification
Consolidated Statements of Cash Flows
Depreciation and amortization, net		(267)
Deferred rent and amortization of intangible assets, liabilities and lease inducements		1,013
Other assets		(746)
Payment of revolving credit facilities, mortgages payable, term notes and principal on SBA 7(a) loan-backed notes		(55,159)
Payment of principal on SBA 7(a) loan-backed notes		7,159
Payment of unsecured revolving lines of credit, revolving credit facility and or term note		48,000
Proceeds from revolving credit facilities and term notes		77,516
Proceeds from unsecured revolving lines of credit, revolving credit facility and or term note		(61,500)
Borrowed funds from the Federal Reserve through the Paycheck Protection Program Liquidity Facility		(16,016)
Payment of deferred costs		(535)
Payment of deferred loan costs		535
Net proceeds from issuance of Preferred Stock		446
Additions to deferred loan costs included in accounts payable and accrued expenses		(221)
Accrued deferred costs		221
Preferred stock offering costs offset against redeemable preferred stock		4
Preferred stock offering costs offset against redeemable preferred stock in permanent equity		(4)
Accrued redeemable preferred stock fees		6
Equity-based payment for management fees		2,663
Payment of management fees and base service fee in preferred stock		(2,663)
Reclassification | Series D Preferred Stock
Consolidated Statements of Cash Flows
Net proceeds from issuance of Preferred Stock		(446)
Accrued redeemable preferred stock fees		$ (6)