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Loans Receivable, Allowance for Credit Losses and Credit Quality - Nonaccrual Loans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Loans Receivable and ACL
Nonaccrual Loans with No ACL	$ 7,233		$ 7,233		$ 9,751
Nonaccrual Loans with an ACL	4,124		4,124		4,105
Total Nonaccrual Loans	11,357		11,357		13,856
Reversal of interest income	82	$ 232	288	$ 232
Residential real estate | One to four-family residential
Loans Receivable and ACL
Nonaccrual Loans with No ACL	2,600		2,600		2,930
Total Nonaccrual Loans	2,600		2,600		2,930
Residential real estate | Home equity
Loans Receivable and ACL
Nonaccrual Loans with No ACL	1,172		1,172		958
Total Nonaccrual Loans	1,172		1,172		958
Residential real estate | Commercial
Loans Receivable and ACL
Nonaccrual Loans with No ACL	809		809		3,005
Total Nonaccrual Loans	809		809		3,005
Residential real estate | Construction & land development
Loans Receivable and ACL
Nonaccrual Loans with No ACL	10		10		10
Total Nonaccrual Loans	10		10		10
Commercial | Commercial and industrial
Loans Receivable and ACL
Nonaccrual Loans with No ACL	562		562		454
Nonaccrual Loans with an ACL	4,124		4,124		4,104
Total Nonaccrual Loans	4,686		4,686		4,558
Consumer
Loans Receivable and ACL
Nonaccrual Loans with No ACL	2,080		2,080		2,394
Nonaccrual Loans with an ACL					1
Total Nonaccrual Loans	$ 2,080		$ 2,080		$ 2,395

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