Real Estate Securities - Activity of Credit Component of Other-than-Temporary Impairments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Activity of the Credit Component of Other-than-Temporary Impairments
Balance at beginning of period	$ 18,580	$ 20,967	$ 18,652	$ 21,037
Additions
Initial credit impairments	0	33	0	76
Reductions
Securities sold, or expected to sell	(6)	(927)	(20)	(1,026)
Securities with no outstanding principal at period end	0	(1,229)	(58)	(1,243)
Balance at End of Period	$ 18,574	$ 18,844	$ 18,574	$ 18,844

Additions [Abstract]

No definition available.

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- Definition

This item represents reductions in the amount of cumulative losses recognized in earnings for other than temporary impairments (OTTI) for which a portion of the impairment had been recognized in other comprehensive income (a component of shareholders' equity) due to securities maturing, being called or fully written down.

+ References

No definition available.

+ Details

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- Definition

Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions [Abstract]

+ References

No definition available.

+ Details

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- Definition

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

+ References

+ Details

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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=SL6284393-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=SL6284393-111563

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- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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