Residential Morgage Securities and MSR Related Assets (Composition of OTTI Charges) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Total OTTI losses	$ (1,259)	$ (63)	$ (1,255)
OTTI recognized in/(reclassified from) OCI	0	(969)	770
OTTI recognized in earnings	$ (1,259)	$ (1,032)	$ (485)

Other than Temporary Impairment Losses, Investments, Portion Recognized in (Reclassified From) OCI

No definition available.

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

+ References

+ Details

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