Investments in Apartment/Mixed Use Joint Ventures as of December 31, 2021 (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	$ 493,324	$ 472,317
Cash and cash equivalents	7,937	2,987
Unrealized rents & receivables	5,577	4,342
Deferred costs	3,802	898
Total Assets	701,084	678,190	$ 536,360
Secured notes payable	276,801	222,635
Other liabilities	11,023	28,253
Capital – Third Parties	407,145	396,423
Total Liabilities and Capital	701,084	678,190
Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	510,640	480,544
Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	135,333	139,981
Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	87,483	89,675
Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	510,640	480,544
Riverfront Holdings I I L L C [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net		0
Cash and cash equivalents		0
Unrealized rents & receivables		0
Deferred costs		0
Secured notes payable		0
Other liabilities		0
Riverfront Holdings I I L L C [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets		0
Riverfront Holdings I I L L C [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP		0
Riverfront Holdings I I L L C [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties		0
Riverfront Holdings I I L L C [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital		0
Bryant Street Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	192,904	199,730
Cash and cash equivalents	1,349	1,123
Unrealized rents & receivables	5,128	2,925
Deferred costs	393	304
Secured notes payable	129,263	119,201
Other liabilities	2,338	9,066
Bryant Street Partnerships [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	199,774	204,082
Bryant Street Partnerships [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	53,553	57,555
Bryant Street Partnerships [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	14,620	18,260
Bryant Street Partnerships [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	199,774	204,082
D S T Hickory Creek [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net		43,840
Cash and cash equivalents		827
Unrealized rents & receivables		1,044
Deferred costs		337
Secured notes payable		29,337
Other liabilities		115
D S T Hickory Creek [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	0	46,048
D S T Hickory Creek [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP		4,423
D S T Hickory Creek [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties		12,173
D S T Hickory Creek [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital		46,048
Half St Owner L L C [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	130,616	93,504
Cash and cash equivalents	359	428
Unrealized rents & receivables	14	0
Deferred costs	139	0
Secured notes payable	66,584	18,404
Other liabilities	5,328	14,470
Half St Owner L L C [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	131,128	93,932
Half St Owner L L C [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	36,348	37,478
Half St Owner L L C [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	22,868	23,580
Half St Owner L L C [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	131,128	93,932
Greenville Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	95,883	87,421
Cash and cash equivalents	567	279
Unrealized rents & receivables	13	5
Deferred costs	88	26
Secured notes payable	64,954	44,309
Other liabilities	3,014	4,462
Greenville Partnerships [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	96,551	87,731
Greenville Partnerships [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	11,087	15,584
Greenville Partnerships [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	17,496	23,376
Greenville Partnerships [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	96,551	87,731
Apartment Mixed Use [Member]
Schedule of Equity Method Investments [Line Items]
Investments in real estate, net	452,411	424,495
Cash and cash equivalents	7,772	2,657
Unrealized rents & receivables	5,155	3,974
Deferred costs	3,526	667
Secured notes payable	276,801	211,251
Other liabilities	10,685	28,113
Apartment Mixed Use [Member] | Real Estate Total Assets [Member]
Schedule of Equity Method Investments [Line Items]
Total Assets	468,864	431,793
Apartment Mixed Use [Member] | Real Estate Partnership F R P [Member]
Schedule of Equity Method Investments [Line Items]
Capital - FRP	106,041	115,040
Apartment Mixed Use [Member] | Real Estate Partnership Third Parties [Member]
Schedule of Equity Method Investments [Line Items]
Capital – Third Parties	75,337	77,389
Apartment Mixed Use [Member] | Real Estate Partnership Total Liabilities And Capital [Member]
Schedule of Equity Method Investments [Line Items]
Total Liabilities and Capital	$ 468,864	$ 431,793