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Securities (Other-Than-Temporary Impairment) (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) security | Dec. 31, 2018 USD ($) security | Dec. 31, 2017 USD ($)
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 101 | 184 |
Collateralized loan obligations (“CLOs”) |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 3 |  |
Mortgage backed securities issued by us government agencies and government sponsored enterprise |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 57 | 108 |
U.S. government agency and U.S. government sponsored enterprise debt securities |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 14 |  |
U.S. Treasury securities |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
Number of available-for-sale debt securities in an unrealized loss position |  | 19 |
Foreign bonds |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
Number of available-for-sale debt securities in an unrealized loss position |  | 16 |
Investment securities available for sale |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings |  |  |
OTTI credit losses | $ | $ 0 | $ 0 | $ 0

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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455 + 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 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 (b) -URI http://asc.fasb.org/extlink&oid=118939692&loc=SL6284393-111563 + Details
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