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Investment Securities - Textual (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities valued at less than historical cost, amount | $ 710,600,000 |  | $ 710,600,000 |  | $ 1,700,000,000
Securities valued at less than historical cost (as percent) | 29.60% |  | 29.60% |  | 70.30%
Securities pledged as collateral | $ 1,120,000,000 |  | $ 1,120,000,000 |  | $ 1,020,000,000.00
Realized gains | 7,600,000 | $ 41,000 | 12,900,000 | $ 54,000 |
Realized losses | 3,000 | $ 0 | $ 3,000 | $ 1,000 |
Bonds |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Realized gains | 7,300,000 |  |  |  |
Bonds sold, amount | $ 89,000,000 |  |  |  |

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- Definition Unrealized loss position which are categorized as held-to-maturity or available-for-sale. + References No definition available. + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized as held-to-maturity or available-for-sale as a percentage of the total held-to-maturity and available-for-sale investment portfolio. + References No definition available. + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with interest rate reset through auction process, sold at par value. + References No definition available. + Details
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- Definition Amount of realized gain on 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 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563 + Details
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- Definition Amount of realized loss on 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 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563 + Details
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- Definition Amount of restricted 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 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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