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Securities Available-for-Sale - Schedule of amortized cost and fair value of securities available-for-sale (Detail) - USD ($) $ in Thousands | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Amortized Cost | $ 123,474 |  | $ 120,401
Gross Unrealized Gains | 229 |  | 180
Gross Unrealized Losses | (13,807) |  | (14,481)
Fair Value | 109,896 |  | 106,100
U.S. Government-sponsored enterprises obligations [Member] |  |  |
Amortized Cost | 2,178 |  | 2,191
Gross Unrealized Losses | (338) |  | (365)
Fair Value | 1,840 |  | 1,826
U.S. Government agency small business administration pools guaranteed by SBA [Member] |  |  |
Amortized Cost | 8,965 | [1] | 9,475
Gross Unrealized Losses | (1,177) |  | (1,116)
Fair Value | 7,788 | [1] | 8,359
Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member] |  |  |
Amortized Cost | 6,594 | [1] | 6,922
Gross Unrealized Gains |  |  | 8
Gross Unrealized Losses | (730) |  | (708)
Fair Value | 5,864 | [1] | 6,222
Residential mortgage backed securities [Member] |  |  |
Amortized Cost | 26,144 | [1] | 26,390
Gross Unrealized Losses | (4,472) |  | (4,567)
Fair Value | 21,672 | [1] | 21,823
Municipal bonds [Member] |  |  |
Amortized Cost | 70,870 |  | 69,373
Gross Unrealized Gains | 229 |  | 172
Gross Unrealized Losses | (5,958) |  | (7,129)
Fair Value | 65,141 |  | 62,416
Corporate debt [Member] |  |  |
Amortized Cost | 500 |  | 500
Gross Unrealized Losses | (15) |  | (3)
Fair Value | 485 |  | 497
Corporate subordinated debt [Member] |  |  |
Amortized Cost | 8,223 |  | 5,550
Gross Unrealized Losses | (1,117) |  | (593)
Fair Value | $ 7,106 |  | $ 4,957
[1] | Actual maturities for these debt securities are dependent upon the interest rate environment and prepayments on the underlying loans.

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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