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Securities (Narrative) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 USD ($) security | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) security | Jun. 30, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Proceeds from Sale of Debt Securities, Available-for-sale | $ | $ 175,586 | $ 12,569 | $ 259,554 | $ 32,330
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 228 |  | 228 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 230 |  | 230 |
Municipal Bonds [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 126 |  | 126 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 134 |  | 134 |
U.S. Government and Government-Sponsored Enterprise Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 12 |  | 12 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 13 |  | 13 |
US Government Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 0 |  | 0 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 1 |  | 1 |

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- Definition Amount of cash inflow from sale of 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3151-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
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