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Fair Value Measurements - Estimated Fair Values, Related Carrying Amounts, and Valuation Level of the Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Level 1
Financial Assets
Cash and cash equivalents	$ 295,377	$ 363,855
Accrued interest receivable	21,074	19,685
Financial Liabilities
Deposits, other than time deposits	2,418,955	2,214,372
Level 2
Financial Assets
Federal home Loan Bank stock	11,541	6,728
Federal Reserve Bank stock	12,831	12,142
Bank owned life insurance ("BOLI")	56,342	102,785
Financial Liabilities
Time deposits	2,147,754	1,964,801
FHLB borrowings	41,337	120,778
Level 3
Financial Assets
Loans receivable, net	4,613,357	4,196,079
Non-public investments	20,159	5,494
Carrying Value
Financial Assets
Cash and cash equivalents	295,377	363,855
Loans receivable, net	4,673,077	4,294,408
Accrued interest receivable	21,074	19,685
Federal home Loan Bank stock	11,541	6,728
Federal Reserve Bank stock	12,831	12,142
Non-public investments	20,159	5,494
Bank owned life insurance ("BOLI")	56,342	102,785
Financial Liabilities
Deposits, other than time deposits	2,418,955	2,214,372
Time deposits	2,146,709	1,963,280
FHLB borrowings	41,453	120,835
Fair Value
Financial Assets
Cash and cash equivalents	295,377	363,855
Loans receivable, net	4,613,357	4,196,079
Accrued interest receivable	21,074	19,685
Federal home Loan Bank stock	11,541	6,728
Federal Reserve Bank stock	12,831	12,142
Non-public investments	20,159	5,494
Bank owned life insurance ("BOLI")	56,342	102,785
Financial Liabilities
Deposits, other than time deposits	2,418,955	2,214,372
Time deposits	2,147,754	1,964,801
FHLB borrowings	$ 41,337	$ 120,778

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Fair value portion of accrued interest receivable.

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Fair value portion of investments in Federal Reserve Bank stock.

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- Definition

Fair value portion of noninterest-bearing demand deposits.

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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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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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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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