Investment Securities - Credit Quality Indicators (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	$ 84,994	$ 90,766
AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	76,915
AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	7,660
Not Rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	419
U.S. Treasury and U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	25,453
U.S. Treasury and U.S. government agencies | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	25,453
U.S. Treasury and U.S. government agencies | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
U.S. Treasury and U.S. government agencies | Not Rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Mortgage-backed securities, residential
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	36,965	39,276
Mortgage-backed securities, residential | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	36,965
Mortgage-backed securities, residential | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Mortgage-backed securities, residential | Not Rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Collateralized mortgage obligations, residential
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	11,437	14,590
Collateralized mortgage obligations, residential | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	11,437
Collateralized mortgage obligations, residential | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Collateralized mortgage obligations, residential | Not Rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Mortgage-backed securities, multifamily
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	693	705
Mortgage-backed securities, multifamily | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	693
Mortgage-backed securities, multifamily | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Mortgage-backed securities, multifamily | Not Rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	0
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	10,446	$ 10,630
Obligations of states and political subdivisions | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	2,367
Obligations of states and political subdivisions | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	7,660
Obligations of states and political subdivisions | Not Rated
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total securities	$ 419