Fair Value Measurements - Non-Recurring Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value
Investment in unconsolidated entities	$ 118,861	$ 156,132
Impairment Loss
Investment properties, total impairment loss	2,359	3,510	$ 27,754
Investment in unconsolidated entities, impairment loss	0	29,933	0
Fair Value, Measurements, Nonrecurring
Impairment Loss
Investment properties, total impairment loss	2,359	3,510	27,754
Investment in unconsolidated entities, impairment loss	0	29,933	0
Total impairment losses	2,359	33,443	27,754
Fair Value, Measurements, Nonrecurring \| Level 3
Fair Value
Investment properties	42,250	64,075	105,900
Investment in unconsolidated entities	$ 0	$ 30,049	$ 0

Impairment gain (losses).

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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.

+ References

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

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-Publisher FASB
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-Section 35
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Amount of investment in equity method investee and investment in and advance to affiliate.

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- Definition

Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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