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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 915,068	$ 925,198
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	61,916	62,034
Corporate bonds
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	30,000	30,000
Aaa / AAA | Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	42,474	42,577
Aaa / AAA | Corporate bonds
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	0	0
Aa2 / AA | Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	19,442	19,457
Aa2 / AA | Corporate bonds
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	0	0
A2 / A | Obligations of state and political subdivisions
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	0	0
A2 / A | Corporate bonds
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Debt securities, held-to-maturity	$ 30,000	$ 30,000

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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