Fair Value of Financial Instruments and Fair Value Measurements - Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 01, 2022
Assets
Investment securities available for sale, at fair value	$ 399,547	$ 432,553
Investment securities held to maturity	385,065	411,264	$ 477,000
Carrying Value
Assets
Cash and short-term investments	141,340	80,678
Investment securities available for sale, at fair value	399,547	432,553
Investment securities held to maturity	451,056	465,858
Other investments, at cost	17,323	13,793
Loans held for sale	27,246	17,743
Loans, net	1,847,603	1,720,978
Derivative instruments	914
Liabilities
Deposits	2,591,332	2,490,997
Federal Home Loan Bank advances	185,000	125,000
Other borrowings	63,422	78,352
Estimated Fair Value
Assets
Cash and short-term investments	141,340	80,678
Investment securities available for sale, at fair value	399,547	432,553
Investment securities held to maturity	385,065	411,264
Other investments, at cost	17,323	13,793
Loans held for sale	27,246	17,743
Loans, net	1,638,269	1,469,707
Derivative instruments	914
Liabilities
Deposits	2,582,790	2,489,481
Federal Home Loan Bank advances	189,065	125,163
Other borrowings	48,475	69,930
Estimated Fair Value \| Level 1
Assets
Cash and short-term investments	141,340	80,678
Investment securities available for sale, at fair value	0	0
Investment securities held to maturity	0	0
Other investments, at cost	0	0
Loans held for sale	0	0
Loans, net	0	0
Derivative instruments	0
Liabilities
Deposits	0	0
Federal Home Loan Bank advances	0	0
Other borrowings	0	0
Estimated Fair Value \| Level 2
Assets
Cash and short-term investments	0	0
Investment securities available for sale, at fair value	386,102	416,957
Investment securities held to maturity	385,065	411,264
Other investments, at cost	17,323	13,003
Loans held for sale	27,246	17,743
Loans, net	0	0
Derivative instruments	914
Liabilities
Deposits	2,582,790	2,489,481
Federal Home Loan Bank advances	189,065	125,163
Other borrowings	48,475	69,930
Estimated Fair Value \| Level 3
Assets
Cash and short-term investments	0	0
Investment securities available for sale, at fair value	13,445	15,596
Investment securities held to maturity	0	0
Other investments, at cost	0	790
Loans held for sale	0	0
Loans, net	1,638,269	1,469,707
Derivative instruments	0
Liabilities
Deposits	0	0
Federal Home Loan Bank advances	0	0
Other borrowings	$ 0	$ 0

Other Investments, Fair Value Disclosure

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Fair value of Federal Home Loan Bank (FHLBank) advances carried under the fair value option.

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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