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Residential Mortgage Securities and MSR Related Assets (Composition of OTTI Charges) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract] |  |  |
Total OTTI losses | $ (264) | $ (1,259) | $ (63)
OTTI recognized in/(reclassified from) OCI | 84 | 0 | (969)
OTTI recognized in earnings | $ (180) | $ (1,259) | $ (1,032)

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- Definition Other than Temporary Impairment Losses, Investments, Portion Recognized in (Reclassified From) OCI + References No definition available. + Details
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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=118954083&loc=SL6284422-111562 + Details
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- Definition Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings. + 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=118954083&loc=SL6284422-111562 + Details
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