Real Estate - Assets and Liabilities Held-for-sale (Details) - USD ($) $ in Thousands		3 Months Ended
	Apr. 07, 2021	Mar. 31, 2021	Dec. 31, 2020
Held-for-sale | Burnett Plaza
Real estate assets and other assets held for sale
Operating property, net of accumulated depreciation of $8,123 in 2021 and 2020		$ 114,603	$ 106,864
Notes and accounts receivable		696	439
Deferred rents receivable		2,742	2,480
Intangible assets, net of accumulated amortization of $5,912 and $6,065 in 2021 and 2020, respectively		15,978	15,830
Other assets		165	133
Total real estate assets and other assets held for sale		134,184	125,746
Liabilities of real estate assets held for sale
Accounts payable and accrued expenses		4,895	7,399
Deferred income		54	44
Intangible liabilities, net of accumulated amortization of $1,106 and $1,205 in 2021 and 2020, respectively		3,114	3,014
Other liabilities		2,381	2,149
Total liabilities of real estate assets held for sale		10,444	12,606
Operating properties, net of accumulated depreciation		8,123	8,123
Intangible assets, net of accumulated amortization		5,912	6,065
Intangible liabilities, net of accumulated amortization		1,106	$ 1,205
Discontinued Operations, Disposed of by Sale
Liabilities of real estate assets held for sale
Gain from sale of property		$ 90,300
Discontinued Operations, Disposed of by Sale | Burnett Plaza | Subsequent Event
Liabilities of real estate assets held for sale
Sales Price	$ 137,500
Gain from sale of property	$ 364