Real Estate - Discontinued Operations Results of Retail Portfolio (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Results of Discontinued Operations
Loss on extinguishment of debt	$ 0	$ (764)	$ 0	$ (764)
Gain on sale of real estate	0	339,024	0	339,024
Income from discontinued operations	$ 0	$ 341,202	$ 0	$ 354,418
Discontinued operations, basic (in dollars per share)	$ 0	$ 4.24	$ 0	$ 4.41
Discontinued operations, diluted (in dollars per share)	$ 0	$ 4.24	$ 0	$ 4.41
Retail Portfolio \| Discontinued Operations
Results of Discontinued Operations
Real estate rental revenue		$ 4,126		$ 28,200
Real estate expenses		(1,095)		(6,803)
Depreciation and amortization		(59)		(4,926)
Interest expense		(30)		(313)
Loss on extinguishment of debt		(764)		(764)
Gain on sale of real estate		339,024		339,024
Income from discontinued operations		341,202		354,418
Capital expenditures		$ 0		$ 809

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