Investment Securities - Schedule of Fair Value and Unrealized Losses Aggregated by Investment Category And Length of Time (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	$ 24,673	$ 15,720
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(342)	(130)
Available-for-sale securities, 12 Months or Longer, Fair Value	20,970	6,785
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(770)	(150)
Available-for-sale securities, Fair Value	45,643	22,505
Available-for-sale securities, Unrealized Loss	(1,112)	(280)
Collateralized Mortgage Backed [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	11,922	14,971
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(215)	(129)
Available-for-sale securities, 12 Months or Longer, Fair Value	12,043
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(575)
Available-for-sale securities, Fair Value	23,965	14,971
Available-for-sale securities, Unrealized Loss	(790)	(129)
Subordinated Debt [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	4,673	749
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(47)	(1)
Available-for-sale securities, Fair Value	4,673	749
Available-for-sale securities, Unrealized Loss	(47)	(1)
Taxable Municipal Securities [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	5,484
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(63)
Available-for-sale securities, 12 Months or Longer, Fair Value	3,482
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(97)
Available-for-sale securities, Fair Value	8,966
Available-for-sale securities, Unrealized Loss	(160)
U.S Government Agencies [Member]
Investment Securities [Line Items]
Available-for-sale securities, 12 Months or Longer, Fair Value	5,445	6,785
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(98)	(150)
Available-for-sale securities, Fair Value	5,445	6,785
Available-for-sale securities, Unrealized Loss	(98)	$ (150)
Tax-Exempt Municipal Securities [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	2,594
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(17)
Available-for-sale securities, Fair Value	2,594
Available-for-sale securities, Unrealized Loss	$ (17)

Investment Securities [Line Items]

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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-Publisher FASB
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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, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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