Fair Value Measurement - Fair Value, by Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financial instruments - assets
Available for sale, at fair value	$ 237,878	$ 62,862
Held-to-maturity, fair value	348,505	330,626
Loans held for sale	2,475	11,514
Loan balance	768,500	1,000,000
Other assets:	0	0
Level 1
Financial instruments - assets
Cash and cash equivalents	60,881	913,752
Available for sale, at fair value	0	0
Held-to-maturity, fair value	0	0
Equity securities	430	500
Loans held for sale	0	0
Loan balance	0	0
Restricted investment in bank stocks	8,315	9,134
Accrued interest receivable	18,405	10,779
Other assets:	0	0
Mortgage banking derivative assets	0	0
Financial instruments - liabilities
Deposits	0	0
Short-term debt	0
Long-term debt	0	0
Subordinated debt	0	0
Accrued interest payable	2,303	1,791
Interest rate swap agreements	0	0
Mortgage banking derivative liabilities	0	0
Level 2
Financial instruments - assets
Cash and cash equivalents	0	0
Available for sale, at fair value	237,878	62,862
Held-to-maturity, fair value	348,505	330,626
Equity securities	0	0
Loans held for sale	2,475	11,514
Loan balance	0	0
Restricted investment in bank stocks	0	0
Accrued interest receivable	0	0
Other assets:	11,697	1,808
Mortgage banking derivative assets	46	75
Financial instruments - liabilities
Deposits	3,761,260	4,046,217
Short-term debt	102,647
Long-term debt	1,069	77,455
Subordinated debt	55,917	74,553
Accrued interest payable	0	0
Interest rate swap agreements	11,697	1,808
Mortgage banking derivative liabilities	40	22
Level 3
Financial instruments - assets
Cash and cash equivalents	0	0
Available for sale, at fair value	0	0
Held-to-maturity, fair value	0	0
Equity securities	0	0
Loans held for sale	0	0
Loan balance	3,439,948	3,118,416
Restricted investment in bank stocks	0	0
Accrued interest receivable	0	0
Other assets:	0	0
Mortgage banking derivative assets	0	0
Financial instruments - liabilities
Deposits	0	0
Short-term debt	0
Long-term debt	0	0
Subordinated debt	0	0
Accrued interest payable	0	0
Interest rate swap agreements	0	0
Mortgage banking derivative liabilities	0	0
Carrying Amount
Financial instruments - assets
Cash and cash equivalents	60,881	913,752
Available for sale, at fair value	237,878	62,862
Held-to-maturity, fair value	399,494	329,257
Equity securities	430	500
Loans held for sale	2,475	11,514
Loan balance	3,495,162	3,089,799
Restricted investment in bank stocks	8,315	9,134
Accrued interest receivable	18,405	10,779
Other assets:	11,697	1,808
Mortgage banking derivative assets	46	75
Financial instruments - liabilities
Deposits	3,778,331	4,002,016
Short-term debt	102,647
Long-term debt	1,119	77,890
Subordinated debt	56,941	74,274
Accrued interest payable	2,303	1,791
Interest rate swap agreements	11,697	1,808
Mortgage banking derivative liabilities	40	22
Total
Financial instruments - assets
Cash and cash equivalents	60,881	913,752
Available for sale, at fair value	237,878	62,862
Held-to-maturity, fair value	348,505	330,626
Equity securities	430	500
Loans held for sale	2,475	11,514
Loan balance	3,439,948	3,118,416
Restricted investment in bank stocks	8,315	9,134
Accrued interest receivable	18,405	10,779
Other assets:	11,697	1,808
Mortgage banking derivative assets	46	75
Financial instruments - liabilities
Deposits	3,761,260	4,046,217
Short-term debt	102,647
Long-term debt	1,069	77,455
Subordinated debt	55,917	74,553
Accrued interest payable	2,303	1,791
Interest rate swap agreements	11,697	1,808
Mortgage banking derivative liabilities	$ 40	$ 22

Accrued interest receivable fair value disclosure.

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Mortgage banking derivative liabilities.

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Fair value portion of accrued expenses.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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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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- Definition

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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Fair value portion of mortgage loans held-for-sale.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item represents the amount of short-term debt existing as of the balance sheet date.

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