Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Held-to-maturity
Beginning balance	$ 3,214	$ 3,214	$ 3,214	$ 1,388
Provision for credit loss expense	0	0	0	1,826
Net increase (decrease) in allowance on previously impaired securities	0	0	0	0
Ending balance	3,214	3,214	3,214	3,214
State and political subdivisions
Held-to-maturity
Beginning balance	191	934	2,006	110
Provision for credit loss expense	0	0	0	824
Net increase (decrease) in allowance on previously impaired securities	36	586	(1,779)	586
Ending balance	227	1,520	227	1,520
Other securities
Held-to-maturity
Beginning balance	3,023	2,280	1,208	1,278
Provision for credit loss expense	0	0	0	1,002
Net increase (decrease) in allowance on previously impaired securities	(36)	(586)	1,779	(586)
Ending balance	$ 2,987	$ 1,694	$ 2,987	$ 1,694

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

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

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- Definition

Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on 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 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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