Operating Real Estate - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Real Estate [Line Items]
Depreciation	$ 16,000	$ 15,500	$ 32,000	$ 31,100
Impairment loss			91,400	10,100
Impairment loss	$ 91,437	$ 10,146	91,437	$ 10,146
Building and Building Improvements
Real Estate [Line Items]
Impairment loss			$ 148,700		$ 58,000

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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