Securities - Interest Income on Securities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Investments, Debt Securities [Abstract]
U.S. Treasury	$ 734	$ 2,315	$ 3,737	$ 6,404
State and political subdivisions	11,424	12,994	34,743	41,151
Corporate bonds and other	1,665	1,654	4,875	5,182
MBS	14,174	11,976	40,737	33,179
Total interest income on securities	$ 27,997	$ 28,939	$ 84,092	$ 85,916

Investments, Debt Securities [Abstract]

No definition available.

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- Definition

The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

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No definition available.

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on corporate debt securities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securitized, pass-through debt securities collateralized by real estate mortgage loans.

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- Definition

Interest income, including any amortization and accretion (as applicable) of discounts and premiums, derived from debt securities issued by municipal governments, local taxing districts and US state government agencies.

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- Definition

Interest income on US treasury securities. US treasury securities are negotiable debt obligations of the US government, secured by its full faith and credit and issued at various schedules and maturities. The income from treasury securities is exempt from state and local, but not federal, taxes. There are three types of securities issued by the US treasury (bonds, bills, and notes), which are distinguished by the amount of time from the initial sale of the bond to maturity.

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