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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 109,036	$ 137,413
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	1,667	$ 3,513
Moody's And/Or Standard & Poor's AA Rating | Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	1,461
Moody's And/Or Standard & Poor's A Rating | Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 206

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Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

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