Securities - Interest Income on Securities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investments, Debt Securities [Abstract]
US Treasury	$ 182	$ 0	$ 388	$ 0
State and political subdivisions	12,223	9,787	33,568	26,281
Corporate bonds and other	1,097	391	2,928	568
MBS	4,405	7,048	15,140	27,626
Total interest income on securities	$ 17,907	$ 17,226	$ 52,024	$ 54,475

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.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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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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+ Details

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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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+ Details

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on U.S. Treasury securities and other U.S. government securities.

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+ Details

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