Investment Securities - Summary of Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	$ 26,465	$ 14,861
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(238)	(92)
Available-for-sale Securities, 12 Months or Longer, Fair Value	1,258	1,539
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(14)	(30)
Available-for-sale Securities, Fair Value, Total	27,723	16,400
Available-for-sale Securities, Unrealized Losses, Total	(252)	(122)
Small Business Administration Loan Pools [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	1,761	2,059
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(25)	(9)
Available-for-sale Securities, 12 Months or Longer, Fair Value	1,258	1,539
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(14)	(30)
Available-for-sale Securities, Fair Value, Total	3,019	3,598
Available-for-sale Securities, Unrealized Losses, Total	(39)	(39)
Obligations of state and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	3,644	557
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(51)	(3)
Available-for-sale Securities, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	0	0
Available-for-sale Securities, Fair Value, Total	3,644	557
Available-for-sale Securities, Unrealized Losses, Total	(51)	(3)
Mortgage-backed securities in government-sponsored entities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	21,060	12,245
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(162)	(80)
Available-for-sale Securities, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	0	0
Available-for-sale Securities, Fair Value, Total	21,060	12,245
Available-for-sale Securities, Unrealized Losses, Total	$ (162)	$ (80)

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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