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Securities - Temporarily Impaired Securities (Details) $ in Thousands | Jun. 30, 2019 USD ($) investment | Dec. 31, 2018 USD ($)
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Gross Unrealized Loss | $ | $ (513) | $ (2,428)
Number of Securities | investment | 55 |
US Government-sponsored Enterprises Debt Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Gross Unrealized Loss | $ | $ (65) | (389)
Number of Securities | investment | 3 |
Municipal securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Gross Unrealized Loss | $ | $ (17) | (213)
Number of Securities | investment | 4 |
Other debt securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Gross Unrealized Loss | $ | $ (42) | (67)
Number of Securities | investment | 1 |
Mortgage-backed securities (GSEs) [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Gross Unrealized Loss | $ | $ (389) | $ (1,759)
Number of Securities | investment | 47 |

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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, 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 7 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455 + Details
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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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