Dispositions, Real Property Held for Sale and Impairment - Dispositions and Assets Held for Sale (Details) - Disposal group, disposed of by sale, not discontinued operations - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues:
Total revenues	$ 19,441	$ 107,997	$ 48,943	$ 253,500
Expenses:
Interest expense	323	3,395	1,438	8,302
Property operating expenses	3,034	50,297	6,203	116,515
Provision for depreciation	1,397	28,090	7,396	54,004
Total expenses	4,754	81,782	15,037	178,821
Income (loss) from real estate dispositions, net	$ 14,687	$ 26,215	$ 33,906	$ 74,679

Amount of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of interest expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Expenses, discontinued

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