Securities - Credit Quality Indicators (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	$ 90,766	$ 123,975
AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	83,095
AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	7,671
U.S. Treasury and U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	25,565
U.S. Treasury and U.S. government agencies | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	25,565
U.S. Treasury and U.S. government agencies | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	0
Mortgage-backed securities, residential
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	39,276	48,082
Mortgage-backed securities, residential | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	39,276
Mortgage-backed securities, residential | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	0
Collateralized mortgage obligations, residential
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	14,590	28,147
Collateralized mortgage obligations, residential | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	14,590
Collateralized mortgage obligations, residential | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	0
Mortgage-backed securities, multifamily
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	705	1,750
Mortgage-backed securities, multifamily | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	705
Mortgage-backed securities, multifamily | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	0
Obligations of states and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	10,630	$ 12,161
Obligations of states and political subdivisions | AAA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	2,959
Obligations of states and political subdivisions | AA
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Investment securities, held to maturity	$ 7,671