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Investment Securities - Narrative (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 USD ($) security | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) security segment | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Available-for-sale securities, gross realized gains (losses) | $ 0 | $ 0 | $ 0 | $ 0 |
OTTI losses, investments | 0 | 0 | $ 0 | 0 |
Number of general segments for the segregation of portfolio | segment |  |  | 2 |  |
Unrealized (loss) gain on fair value of marketable equity securities | (14,000) | $ 4,000 | $ (75,000) | $ 89,000 |
Held-to-maturity securities | 0 |  | 0 |  | $ 0
Investment securities | $ 0 |  | $ 0 |  | 0
Municipal bonds |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Number of impaired securities | security | 28 |  | 28 |  |
U.S. Government agencies |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Number of impaired securities | security | 6 |  | 6 |  |
U.S. Government sponsored entities & agencies collateralized by mortgage obligations |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Number of impaired securities | security | 7 |  | 7 |  |
Carrying Amount |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Fair value of available-for-sale securities pledged as collateral for FHLB borrowings | $ 98,069,000 |  | $ 98,069,000 |  |
Investment securities | 165,508,000 |  | 165,508,000 |  | 86,192,000
Estimated Fair Value |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Fair value of available-for-sale securities pledged as collateral for FHLB borrowings | 98,744,000 |  | 98,744,000 |  |
Investment securities | $ 165,508,000 |  | $ 165,508,000 |  | $ 86,192,000

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- Definition Amount of realized gain (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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&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 954 -SubTopic 210 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120413173&loc=SL6242262-115580 Reference 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 210 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120413209&loc=SL6242269-115581 + 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=123581744&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=124269663&loc=SL82922888-210455 + Details
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