RELATED PARTY TRANSACTIONS AND TRANSACTIONS WITH AFFILIATES (Details)									1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 20, 2019 USD ($)	Apr. 25, 2019 USD ($)	Apr. 01, 2019 USD ($)	Nov. 28, 2018 USD ($)	Oct. 04, 2018 USD ($)	Jun. 26, 2018 USD ($) $ / shares shares	Mar. 09, 2018 USD ($) $ / shares shares	Jan. 08, 2018 USD ($) $ / shares shares	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2019 USD ($)
Base management fee percentage on first $500 million share capital								0.50%
Base management fee percentage in excess of $500 million share capital								0.25%
Annual reimbursement cap until 2019								$ 2,500,000
Annual reimbursement cap after 2019 until share capital exceeds of $500 million								$ 3,500,000
Renewal period of the agreement								2 years
Agreement Violation Termination Fee Includes An Amount Times Sum of Average Annual Base and Incentive Management Fee								3
Agreement Violation Termination Fee Includes An Amount Times Sum of Average Energy Capital Business Expense Reimbursement and Employee Cost Reimbursement Expense								1
Termination fee period								2 years
Aggregate cost of common stock shares issued						$ 4,300,000	$ 4,100,000
Consideration on disposal									$ 57,000,000	$ 57,000,000		$ 57,000,000
Notes receivable									57,000,000	57,000,000		$ 57,000,000
Interest rate for note												5.00%
HFS loan acquired by Hunt									54,100,000	54,100,000	$ 67,299,000	$ 54,100,000	$ 67,299,000
External management fees and reimbursable expenses												$ 7,248,000	6,869,000
Term of note receivable												7 years
Equity Method Investments									316,677,000	316,677,000	155,079,000	$ 316,677,000	155,079,000
Reimbursement of compensation related expenses shareholders equity benchmark amount									500,000,000	500,000,000		500,000,000
Financing Receivable, Net, Unpaid Principal Balance									54,100,000	54,100,000	68,050,000	54,100,000	68,050,000
Carrying value of Loan receivable									54,100,000	54,100,000	67,299,000	54,100,000	67,299,000
Investments in partnerships (includes $289,123 and $8,779 pledged as collateral at December 31, 2019 and 2018, respectively)									316,677,000	316,677,000	155,079,000	316,677,000	155,079,000
Proceeds from the sale of real estate and other investments												2,080,000	1,725,000
Proceeds from loans receivable										13,400,000
Investment in Debt Securities
Net proceeds from sale of affordable house property		$ 13,100,000
Hunt Companies [Member]
Loans and leases receivable from related party					$ 67,000,000				53,600,000
Interest income, related party												3,300,000	2,900,000
Interest Receivable									700,000	700,000	0	700,000	0
Financing Receivable, Net, Unpaid Principal Balance	$ 1,100,000
Carrying value of Loan receivable	300,000
Investments in partnerships (includes $289,123 and $8,779 pledged as collateral at December 31, 2019 and 2018, respectively)	900,000
Proceeds from the sale of real estate and other investments	3,100,000
Gain (loss) on sale of loans and real estate related investments	1,900,000
Proceeds from loans receivable	$ 13,400,000
Hunt Companies [Member] | MGM, Disposition [Member]
HFS loan acquired by Hunt											9,000,000		9,000,000
Price of loan acquired by hunt											9,400,000
Hunt Companies [Member] | External Management Fees and Expenses Reimbursement
Incentive fee								20.00%
External management fee, contract in excess for incentive fee.								7.00%
Related party incentive fee expense												0	0
External management fees and reimbursable expenses												7,200,000	6,900,000
Hunt Companies [Member] | External Management Fees and Expenses Reimbursement | External Manager [Member]
Management fees and expense reimbursements payable									$ 1,200,000	$ 1,200,000	$ 1,100,000	$ 1,200,000	$ 1,100,000
Hunt Companies [Member] | Investment in Debt Securities
Service fees waived by agent		900,000
Hunt Companies [Member] | Common shares in disposition
Shares issued (in shares) | shares						125,000	125,000
Shares issued						$ 4,300,000	$ 4,100,000
Purchase price (per share) | $ / shares						$ 34.00	$ 33.00
Hunt Companies [Member] | Common shares in disposition | Private Placement
Shares issued (in shares) | shares								250,000
Purchase price (per share) | $ / shares								$ 33.50
Hunt Companies [Member] | Investment in Debt Securities
Proceeds from redemption of bonds		$ 900,000
Solar Development Lending, LLC [Member]
Percentage of loan amount contribution				20.00%
Principal amount of fiancing receivable				$ 58,800,000										$ 104,000,000
Solar Development Lending, LLC [Member] | Hunt Companies [Member]
Ownership interest			30.00%
Payments to Acquire Equity Method Investments			$ 11,300,000
Solar Development Lending, LLC [Member] | Hunt Companies [Member]
Percentage of loan amount contribution				30.00%
Solar Development Lending, LLC [Member] | Investment partner
Percentage of loan amount contribution				50.00%
Minimum [Member] | Hunt Companies [Member] | Affordable Housing Partnerships [Member]
Ownership interest	74.25%
Maximum [Member] | Hunt Companies [Member] | Affordable Housing Partnerships [Member]
Ownership interest	74.92%