Securities - Amortized Cost and Fair Value of Securities with Gross Unrealized Gains and Losses (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 439,186	$ 433,962
Gross Unrealized Gains	69	3,032
Gross Unrealized Losses	(48,466)	(7,063)
Fair Value	390,789	429,931
U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	104,507	90,775
Gross Unrealized Losses	(9,829)	(1,598)
Fair Value	94,678	89,177
U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	156,817	159,673
Gross Unrealized Gains		695
Gross Unrealized Losses	(17,050)	(3,482)
Fair Value	139,767	156,886
Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	101,068	118,550
Gross Unrealized Gains		839
Gross Unrealized Losses	(14,141)	(1,462)
Fair Value	86,927	117,927
State and Local Governments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	76,794	64,964
Gross Unrealized Gains	69	1,498
Gross Unrealized Losses	(7,446)	(521)
Fair Value	$ 69,417	$ 65,941

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).

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Amount, before tax, of unrealized loss 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).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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