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Debt Securities Held-to-Maturity - Held-to-Maturity Securities in a Continuous Unrealized Loss Positions (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 USD ($) loan | Mar. 31, 2019 USD ($) | Dec. 31, 2019 USD ($)
Schedule of Held-to-maturity Securities [Line Items] |  |  |
Held-to-maturity securities sold | $ 0 | $ 0 |
Held-to-maturity securities pledged to secure borrowings and deposits | 7,300,000 |  |
Unrealized losses |  |  |
Less than 12 months |  |  | $ 0
12 months or more |  |  | 5,000
Total |  |  | 5,000
Estimated fair value |  |  |
Less than 12 months |  |  | 0
12 months or more |  |  | 378,000
Total |  |  | 378,000
Other-than-temporary impairment charge recognized in earnings | $ 0 | $ 0 |
Mortgage Backed Securities Pass Through Certificates |  |  |
Unrealized losses |  |  |
Less than 12 months |  |  | 0
12 months or more |  |  | 5,000
Total |  |  | 5,000
Estimated fair value |  |  |
Less than 12 months |  |  | 0
12 months or more |  |  | 378,000
Total |  |  | $ 378,000
Number of mortgage-backed securities in unrealized loss position, greater than 12 months (loan) | loan | 0 |  |

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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 + Details
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- Definition Amount of restricted investment in debt security measured at amortized cost (held-to-maturity). + 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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(f)) -URI http://asc.fasb.org/extlink&oid=6488002&loc=d3e600178-122990 + Details
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