Real Estate Activities - Disposition (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sales of interests in real estate			$ 0	$ 1,701	$ 0	$ 1,701
Proceeds from redemption of preferred equity		$ 2,500
Cash proceeds from sales of real estate					29,713	28,079
Gain on sale of preferred equity interest			0	0	0	3,688
Plymouth Meeting Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, consideration	$ 27,000
Cash proceeds from sales of real estate	$ 26,300
Woodland Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sales of interests in real estate			1,100		1,100
Disposal group, consideration			$ 4,800		4,800
Cash proceeds from sales of real estate					$ 3,400
Moorestown Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sales of interests in real estate						8,800
Disposal group, consideration				11,800		11,800
Cash proceeds from sales of real estate						11,700
Francis Scott Key Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sales of interests in real estate						1,700
Disposal group, consideration				$ 2,400		2,400
Cash proceeds from sales of real estate						$ 2,400