Investment Securities - Schedule of Unrealized Loss Positions of Securities Available-for-Sale and Held-to-Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	$ 39,297	$ 24,673
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(3,025)	(342)
Available-for-sale securities, 12 Months or Longer, Fair Value	19,428	20,970
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(1,884)	(770)
Available-for-sale securities, Fair Value	58,725	45,643
Available-for-sale securities, Unrealized Loss	(4,909)	(1,112)
Held-to-maturity securities, Less than 12 Months, Fair Value	1,666
Held-to-maturity securities, Less than 12 Months, Unrealized Loss	(13)
Held-to-maturity securities, Fair Value	1,666
Held-to-maturity securities, Unrealized Loss	(13)
Collateralized Mortgage Backed [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	15,930	11,922
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(943)	(215)
Available-for-sale securities, 12 Months or Longer, Fair Value	11,173	12,043
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(1,368)	(575)
Available-for-sale securities, Fair Value	27,103	23,965
Available-for-sale securities, Unrealized Loss	(2,311)	(790)
Municipal Securities [Member]
Investment Securities [Line Items]
Held-to-maturity securities, Fair Value	1,700
Subordinated Debt [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	7,834	4,673
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(387)	(47)
Available-for-sale securities, Fair Value	7,834	4,673
Available-for-sale securities, Unrealized Loss	(387)	(47)
U.S Government Agencies [Member]
Investment Securities [Line Items]
Available-for-sale securities, 12 Months or Longer, Fair Value	5,108	5,445
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(87)	(98)
Available-for-sale securities, Fair Value	5,108	5,445
Available-for-sale securities, Unrealized Loss	(87)	(98)
Taxable Municipal Securities [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	5,590	5,484
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(528)	(63)
Available-for-sale securities, 12 Months or Longer, Fair Value	3,147	3,482
Available-for-sale securities, 12 Months or Longer, Unrealized Loss	(429)	(97)
Available-for-sale securities, Fair Value	8,737	8,966
Available-for-sale securities, Unrealized Loss	(957)	(160)
Tax-Exempt Municipal Securities [Member]
Investment Securities [Line Items]
Available-for-sale securities, Less than 12 Months, Fair Value	9,943	2,594
Available-for-sale securities, Less than 12 Months, Unrealized Loss	(1,167)	(17)
Available-for-sale securities, Fair Value	9,943	2,594
Available-for-sale securities, Unrealized Loss	(1,167)	$ (17)
Held-to-maturity securities, Less than 12 Months, Fair Value	1,666
Held-to-maturity securities, Less than 12 Months, Unrealized Loss	(13)
Held-to-maturity securities, Fair Value	1,666
Held-to-maturity securities, Unrealized Loss	$ (13)

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.

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