Investment Securities, at Fair Value - Scheduled Maturity of CMBS (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value
Total	$ 26,282	$ 40,974
CMBS [Member]
Amortized Cost
Due after one year through five years	13,721
Due after five years through 10 years	12,207
Amortized Cost	25,928	43,006
Fair Value
Due after one year through five years	14,075
Due after five years through 10 years	12,207
Total	$ 26,282	$ 40,974

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ 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)
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-Section 50
-Paragraph 2
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