Income From Equity Method Investments, Gross

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- Definition

Loss From Equity Method Investments, Gross

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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- Definition

Fair value portion of investments accounted under the equity method.

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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Equity Investments, at Fair Value (Details) - USD ($)	3 Months Ended		9 Months Ended
Equity Investments, at Fair Value (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Gain (loss) from equity investments	$ 8,015,000	$ 9,966,000	$ 22,021,000	$ 14,573,000
Preferred Equity Ownership Interests
Schedule of Equity Method Investments [Line Items]
Gain (loss) from equity investments	(300,000)	6,700	600,000	(4,100,000)
Investment in unconsolidated entities \| Morrocroft Neighborhood Stabilization Fund II, LP
Schedule of Equity Method Investments [Line Items]
Change in fair value, gain (loss)	2,137,000	515,000	4,324,000	1,080,000
Investment in unconsolidated entities \| Headlands Asset Management Fund III (Cayman), LP (Headlands Flagship Opportunity Fund Series I) (1)
Schedule of Equity Method Investments [Line Items]
Change in fair value, gain (loss)	0	5,027,000	(15,000)	7,078,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests
Schedule of Equity Method Investments [Line Items]
Fair Value	227,635,000		227,635,000		$ 182,765,000
Change in fair value, gain (loss)	$ 5,878,000	4,302,000	$ 17,712,000	7,363,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| BBA-EP320 II, L.L.C., BBA-Ten10 II, L.L.C., and Lexington on the Green Apartments, L.L.C. (collectively)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	45.00%		45.00%		45.00%
Fair Value	$ 12,476,000		$ 12,476,000		$ 11,441,000
Change in fair value, gain (loss)	$ 331,000	295,000	$ 1,035,000	898,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Somerset Deerfield Investor, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	45.00%		45.00%		45.00%
Fair Value	$ 19,661,000		$ 19,661,000		$ 18,792,000
Change in fair value, gain (loss)	$ 569,000	472,000	$ 1,711,000	1,259,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| RS SWD Owner, LLC, RS SWD Mitchell Owner, LLC, RS SWD IF Owner, LLC, RS SWD Mullis Owner, LLC, RS SWD JH Mullis Owner, LLC and RS SWD Saltzman Owner, LLC (collectively)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	43.00%		43.00%		43.00%
Fair Value	$ 5,590,000		$ 5,590,000		$ 5,140,000
Change in fair value, gain (loss)	$ 152,000	125,000	$ 450,000	217,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Audubon Mezzanine Holdings, L.L.C. (Series A)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	57.00%		57.00%		57.00%
Fair Value	$ 12,118,000		$ 12,118,000		$ 11,456,000
Change in fair value, gain (loss)	$ 251,000	365,000	$ 972,000	541,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| EP 320 Growth Fund, L.L.C. (Series A) and Turnbury Park Apartments - BC, L.L.C. (Series A) (collectively)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	46.00%		46.00%		46.00%
Fair Value	$ 7,464,000		$ 7,464,000		$ 7,234,000
Change in fair value, gain (loss)	$ 151,000	181,000	$ 571,000	305,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Walnut Creek Properties Holdings, L.L.C.
Schedule of Equity Method Investments [Line Items]
Ownership Interest	36.00%		36.00%		36.00%
Fair Value	$ 9,180,000		$ 9,180,000		$ 8,803,000
Change in fair value, gain (loss)	$ 257,000	280,000	$ 797,000	402,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Towers Property Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	37.00%		37.00%		37.00%
Fair Value	$ 12,712,000		$ 12,712,000		$ 12,119,000
Change in fair value, gain (loss)	$ 348,000	380,000	$ 1,087,000	502,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Mansions Property Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	34.00%		34.00%		34.00%
Fair Value	$ 12,249,000		$ 12,249,000		$ 11,679,000
Change in fair value, gain (loss)	$ 335,000	366,000	$ 1,048,000	484,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Sabina Montgomery Holdings, LLC - Series B and Oakley Shoals Apartments, LLC - Series A (collectively)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	43.00%		43.00%		43.00%
Fair Value	$ 4,465,000		$ 4,465,000		$ 4,320,000
Change in fair value, gain (loss)	$ 89,000	137,000	$ 355,000	190,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Gen1814, LLC - Series A, Highlands - Mtg. Holdings, LLC - Series A, and Polos at Hudson Investments, LLC - Series A (collectively)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	37.00%		37.00%		37.00%
Fair Value	$ 10,297,000		$ 10,297,000		$ 9,966,000
Change in fair value, gain (loss)	$ 204,000	317,000	$ 819,000	430,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Axis Apartments Holdings, LLC, Arbor-Stratford Holdings II, LLC - Series B, Highlands - Mtg. Holdings, LLC - Series B, Oakley Shoals Apartments, LLC - Series C, and Woodland Park Apartments II, LLC (collectively)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	53.00%		53.00%		53.00%
Fair Value	$ 12,721,000		$ 12,721,000		$ 12,337,000
Change in fair value, gain (loss)	$ 252,000	392,000	$ 1,014,000	527,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| DCP Gold Creek, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	44.00%		44.00%		44.00%
Fair Value	$ 6,615,000		$ 6,615,000		$ 6,357,000
Change in fair value, gain (loss)	$ 189,000	203,000	$ 589,000	305,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| 1122 Chicago DE, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	53.00%		53.00%		53.00%
Fair Value	$ 7,593,000		$ 7,593,000		$ 7,222,000
Change in fair value, gain (loss)	$ 229,000	226,000	$ 675,000	462,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Rigsbee Ave Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	56.00%		56.00%		56.00%
Fair Value	$ 11,126,000		$ 11,126,000		$ 10,222,000
Change in fair value, gain (loss)	$ 120,000	326,000	$ 1,335,000	604,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Bighaus, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	42.00%		42.00%		42.00%
Fair Value	$ 15,224,000		$ 15,224,000		$ 14,525,000
Change in fair value, gain (loss)	$ 450,000	237,000	$ 1,328,000	237,000
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| FF/RMI 20 Midtown, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	51.00%		51.00%		51.00%
Fair Value	$ 25,067,000		$ 25,067,000		$ 23,936,000
Change in fair value, gain (loss)	$ 771,000	0	$ 2,275,000	0
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Lurin-RMI, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	38.00%		38.00%		38.00%
Fair Value	$ 7,521,000		$ 7,521,000		$ 7,216,000
Change in fair value, gain (loss)	$ 216,000	0	$ 687,000	0
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| Palms at Cape Coral, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	34.00%		34.00%		0.00%
Fair Value	$ 5,096,000		$ 5,096,000		$ 0
Change in fair value, gain (loss)	$ 189,000	0	$ 189,000	0
Investment in unconsolidated entities \| Multi-Family Preferred Equity Ownership Interests \| America Walks at Port St. Lucie, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	62.00%		62.00%		0.00%
Fair Value	$ 30,460,000		$ 30,460,000		$ 0
Change in fair value, gain (loss)	775,000	0	775,000	0
Investment in unconsolidated entities \| Joint venture equity investments in multi-family properties
Schedule of Equity Method Investments [Line Items]
Fair Value	10,290,000		10,290,000		$ 0
Change in fair value, gain (loss)	$ 0	122,000	$ 0	(949,000)
Loss from equity method investments, gross		8,600,000		9,700,000
Income from equity method investments, gross		8,800,000		8,800,000
Investment in unconsolidated entities \| Joint venture equity investments in multi-family properties \| GWR Cedars Partners, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	70.00%		70.00%		0.00%
Fair Value	$ 3,710,000		$ 3,710,000		$ 0
Investment in unconsolidated entities \| Joint venture equity investments in multi-family properties \| GWR Gateway Partners, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	70.00%		70.00%		0.00%
Fair Value	$ 6,580,000		$ 6,580,000		$ 0
Investment in unconsolidated entities \| Joint venture equity investments in multi-family properties \| The Preserve at Port Royal Venture, LLC
Schedule of Equity Method Investments [Line Items]
Change in fair value, gain (loss)	0	122,000	0	(949,000)
Investment in unconsolidated entities \| Single-Family Equity Ownership Interests
Schedule of Equity Method Investments [Line Items]
Fair Value	17,089,000		17,089,000		$ 76,330,000
Change in fair value, gain (loss)	$ 2,137,000	$ 5,542,000	$ 4,309,000	$ 8,158,000
Investment in unconsolidated entities \| Single-Family Equity Ownership Interests \| Morrocroft Neighborhood Stabilization Fund II, LP
Schedule of Equity Method Investments [Line Items]
Ownership Interest	11.00%		11.00%		11.00%
Fair Value	$ 17,089,000		$ 17,089,000		$ 13,040,000
Investment in unconsolidated entities \| Single-Family Equity Ownership Interests \| Headlands Asset Management Fund III (Cayman), LP (Headlands Flagship Opportunity Fund Series I) (1)
Schedule of Equity Method Investments [Line Items]
Ownership Interest	0.00%		0.00%		49.00%
Fair Value	$ 0		$ 0		$ 63,290,000
Investment in unconsolidated entities \| Preferred Equity Ownership Interests
Schedule of Equity Method Investments [Line Items]
Fair Value	$ 255,014,000		$ 255,014,000		$ 259,095,000