Investments in Apartment/Mixed-use as of June 30, 2023 (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	$ 497,609	$ 493,324
Cash and cash equivalents	9,319	7,937
Unrealized rents & receivables	5,299	5,577
Deferred costs	5,704	3,802
Total Assets	699,896	701,084
Secured notes payable	271,930	276,801
Other liabilities	7,606	11,023
Capital – Third Parties	409,876	407,145
Total Liabilities and Capital	699,896	701,084
Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	517,931	510,640
Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	147,371	135,333
Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	91,024	87,483
Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	517,931	510,640
Buzzard Point Sponsor Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	0	0
Cash and cash equivalents	0	0
Unrealized rents & receivables	0	0
Deferred costs	4,300	2,906
Secured notes payable	0	0
Other liabilities	0	0
Buzzard Point Sponsor Partnership [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	4,300	2,906
Buzzard Point Sponsor Partnership [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	2,150	1,453
Buzzard Point Sponsor Partnership [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	2,150	1,453
Buzzard Point Sponsor Partnership [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	4,300	2,906
Bryant Street Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	189,926	192,904
Cash and cash equivalents	1,137	1,349
Unrealized rents & receivables	4,668	5,128
Deferred costs	801	393
Secured notes payable	116,884	129,263
Other liabilities	2,553	2,338
Bryant Street Partnerships [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	196,532	199,774
Bryant Street Partnerships [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	59,440	53,553
Bryant Street Partnerships [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	17,655	14,620
Bryant Street Partnerships [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	196,532	199,774
Estero Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	33,787	33,008
Cash and cash equivalents	4,725	5,497
Unrealized rents & receivables	29	0
Deferred costs	0	0
Secured notes payable	16,000	16,000
Other liabilities	12	5
Estero Partnership [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	38,541	38,505
Estero Partnership [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	3,605	3,600
Estero Partnership [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	18,924	18,900
Estero Partnership [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	38,541	38,505
Verge [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	129,828	130,616
Cash and cash equivalents	1,917	359
Unrealized rents & receivables	184	14
Deferred costs	172	139
Secured notes payable	71,664	66,584
Other liabilities	1,166	5,328
Verge [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	132,101	131,128
Verge [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	36,421	36,348
Verge [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	22,850	22,868
Verge [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	132,101	131,128
Greenville Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	97,201	95,883
Cash and cash equivalents	1,304	567
Unrealized rents & receivables	26	13
Deferred costs	152	88
Secured notes payable	67,382	64,954
Other liabilities	2,705	3,014
Greenville Partnerships [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	98,683	96,551
Greenville Partnerships [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	11,102	11,087
Greenville Partnerships [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	17,494	17,496
Greenville Partnerships [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	98,683	96,551
Apartment Mixed Use [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	450,742	452,411
Cash and cash equivalents	9,083	7,772
Unrealized rents & receivables	4,907	5,155
Deferred costs	5,425	3,526
Secured notes payable	271,930	276,801
Other liabilities	6,436	10,685
Apartment Mixed Use [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	470,157	468,864
Apartment Mixed Use [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	112,718	106,041
Apartment Mixed Use [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	79,073	75,337
Apartment Mixed Use [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	$ 470,157	$ 468,864