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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 196,801	$ 109,036
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	22,532	1,667
Moody's And/Or Standard & Poor's AAA Rating | Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	7,455	0
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	14,975	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	$ 102	$ 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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