Equity Investments in Unconsolidated Joint Ventures - Summary of Combined Financial Information of Unconsolidated Entities, Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
ASSETS
Investment in real estate, net	$ 1,551,421	$ 1,463,248
Other assets, net	93,307	77,465
TOTAL ASSETS	1,979,690	1,950,040
LIABILITIES AND OWNERS' EQUITY
Notes payable	943,828	1,027,751
Other liabilities	1,073,481	1,148,671
Owners' equity	886,579	782,394
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	1,979,690	1,950,040
RPT's equity investments in unconsolidated joint ventures	216,400	126,333
Equity Method Investment, Nonconsolidated Investee or Group of Investees , R2G
ASSETS
Investment in real estate, net	376,329	226,083
Other assets, net	52,492	26,125
TOTAL ASSETS	428,821	252,208
LIABILITIES AND OWNERS' EQUITY
Notes payable	0	0
Other liabilities	22,786	14,474
Owners' equity	406,035	237,734
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	428,821	252,208
RPT's equity investments in unconsolidated joint ventures	213,008	126,333
Equity Method Investment, Nonconsolidated Investee or Group of Investees RGMZ
ASSETS
Investment in real estate, net	85,604	0
Other assets, net	40,699	0
TOTAL ASSETS	126,303	0
LIABILITIES AND OWNERS' EQUITY
Notes payable	70,696	0
Other liabilities	2,133	0
Owners' equity	53,474	0
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	126,303	0
RPT's equity investments in unconsolidated joint ventures	3,392	0
Equity Method Investment, Nonconsolidated Investee, Other
ASSETS
Investment in real estate, net	0	0
Other assets, net	0	47
TOTAL ASSETS	0	47
LIABILITIES AND OWNERS' EQUITY
Notes payable	0	0
Other liabilities	0	11
Owners' equity	0	36
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	0	47
RPT's equity investments in unconsolidated joint ventures	0	0
Equity Method Investment, Nonconsolidated Investee, Total
ASSETS
Investment in real estate, net	461,933	226,083
Other assets, net	93,191	26,172
TOTAL ASSETS	555,124	252,255
LIABILITIES AND OWNERS' EQUITY
Notes payable	70,696	0
Other liabilities	24,919	14,485
Owners' equity	459,509	237,770
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	555,124	252,255
RPT's equity investments in unconsolidated joint ventures	$ 216,400	$ 126,333