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Securities - Additional Information (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2023 USD ($) Securities	Sep. 30, 2023 USD ($) Securities	Jan. 01, 2023 USD ($)	Dec. 31, 2022 USD ($) Securities
Debt and Equity Securities, FV-NI [Line Items]
Debt securities held-to-maturity fair value	$ 334,625,000	$ 334,625,000		$ 353,901,000
Allowance for credit loss	0	0	$ 7,200,000
Other-than-temporary Impairment Loss, Debt Securities, Available-for-Sale	$ 0	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities	591	591		611
US Treasury Securities [Member] | AA or Better [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	100.00%	100.00%
US States and Political Subdivisions Debt Securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt securities held-to-maturity fair value	$ 153,597,000	$ 153,597,000		$ 162,536,000
US States and Political Subdivisions Debt Securities [Member] | A Rated [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	11.00%	11.00%
US States and Political Subdivisions Debt Securities [Member] | AA or Better [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	86.00%	86.00%
US States and Political Subdivisions Debt Securities [Member] | Unrated [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	3.00%	3.00%
Collateralized Mortgage-Backed Securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt securities held-to-maturity fair value	$ 160,946,000	$ 160,946,000		$ 170,605,000
Collateralized Mortgage-Backed Securities [Member] | AA [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	38.00%	38.00%
Collateralized Mortgage-Backed Securities [Member] | AAA [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	39.00%	39.00%
Collateralized Mortgage-Backed Securities [Member] | Unrated [Member]
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Percent	23.00%	23.00%

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Debt securities percent.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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