Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27476-111563

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

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Fair Value Measurements (Basis of Fair Value Measurements) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets and Liabilities Measured On Recurring and Nonrecurring Basis
Investments in real estate-related securities	$ 36,491	$ 9,599
Gain (loss) on investments in real estate-related securities	2,317	(401)	$ 0
Fair Value, Recurring
Fair Value Assets and Liabilities Measured On Recurring and Nonrecurring Basis
Investments in real estate-related securities	36,491	9,599
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Items (Level 1)
Fair Value Assets and Liabilities Measured On Recurring and Nonrecurring Basis
Investments in real estate-related securities	36,491	9,599
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2)
Fair Value Assets and Liabilities Measured On Recurring and Nonrecurring Basis
Investments in real estate-related securities	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3)
Fair Value Assets and Liabilities Measured On Recurring and Nonrecurring Basis
Investments in real estate-related securities	$ 0	$ 0