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Securities - Available-for-sale Securities in Continuous Loss Position (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
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Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, fair value, less than 12 months | $ 8,915 | $ 41,734
Available-for-sale, gross unrealized losses, less than 12 months | (29) | (542)
Available-for-sale, fair value, 12 months or greater | 106,687 | 89,289
Available-for-sale, gross unrealized losses, 12 months or greater | (2,264) | (2,428)
Securities available for sale | 115,602 | 131,023
Available-for-sale, gross unrealized losses, total | (2,293) | (2,970)
U.S. Government-sponsored enterprises (GSEs) [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, fair value, less than 12 months | 0 | 14,763
Available-for-sale, gross unrealized losses, less than 12 months | 0 | (237)
Available-for-sale, fair value, 12 months or greater | 28,807 | 13,728
Available-for-sale, gross unrealized losses, 12 months or greater | (299) | (389)
Securities available for sale | 28,807 | 28,491
Available-for-sale, gross unrealized losses, total | (299) | (626)
Municipal securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, fair value, less than 12 months | 0 | 16,455
Available-for-sale, gross unrealized losses, less than 12 months | 0 | (150)
Available-for-sale, fair value, 12 months or greater | 4,059 | 4,767
Available-for-sale, gross unrealized losses, 12 months or greater | (838) | (213)
Securities available for sale | 4,059 | 21,222
Available-for-sale, gross unrealized losses, total | (838) | (363)
Other debt securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, fair value, less than 12 months | 0 | 0
Available-for-sale, gross unrealized losses, less than 12 months | 0 | 0
Available-for-sale, fair value, 12 months or greater | 935 | 910
Available-for-sale, gross unrealized losses, 12 months or greater | (43) | (67)
Securities available for sale | 935 | 910
Available-for-sale, gross unrealized losses, total | (43) | (67)
Mortgage-backed securities (GSEs) [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, fair value, less than 12 months | 8,915 | 10,516
Available-for-sale, gross unrealized losses, less than 12 months | (29) | (155)
Available-for-sale, fair value, 12 months or greater | 72,886 | 69,884
Available-for-sale, gross unrealized losses, 12 months or greater | (1,084) | (1,759)
Securities available for sale | 81,801 | 80,400
Available-for-sale, gross unrealized losses, total | $ (1,113) | $ (1,914)

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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), in continuous unrealized loss position for more than 12 months. + 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=82897076&loc=d3e27337-111563 + Details
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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. + 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=82897076&loc=d3e27337-111563 + 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), in continuous unrealized loss position for less than 12 months. + 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=82897076&loc=d3e27337-111563 + Details
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