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Securities (Tables)	9 Months Ended
	Sep. 30, 2025
Investments debt and equity securities [Abstract]
Available-for-sale Securities [Table Text Block]	1 year 1 to 5 5 to 10 After 10 Fair Gross Unrealized Amortized (Dollars in thousands) or less years years years Value Gains Losses Cost September 30, 2025 Agency obligations (a) $ — 35,343 18,093 — 53,436 — 5,164 $ 58,600 Agency MBS (a) — 20,188 17,185 128,210 165,583 — 20,629 186,212 State and political subdivisions — 1,653 9,095 6,653 17,401 1 2,346 19,746 Total available-for-sale $ — 57,184 44,373 134,863 236,420 1 28,139 $ 264,558 December 31, 2024 Agency obligations (a) $ — 26,655 25,756 — 52,411 — 7,734 $ 60,145 Agency MBS (a) 10 19,863 14,904 138,899 173,676 — 28,901 202,577 State and political subdivisions — 966 8,244 7,715 16,925 — 2,901 19,826 Total available-for-sale $ 10 47,484 48,904 146,614 243,012 — 39,536 $ 282,548 (a) Includes securities issued by U.S. government agencies or government -sponsored entities. Expected lives of these securities may differ from contractual maturities because (i) issuers may have the right to call or repay such securities obligations with or without prepayment penalties and (ii) borrowers of the loans included in Agency MBS generally have the right to prepay such loan in whole or in part at any time.
Available-for-sale Securities, Continuous Unrealized Loss Position [Table Text Block]	Less than 12 Months 12 Months or Longer Total Fair Unrealized Fair Unrealized Fair Unrealized (Dollars in thousands) Value Losses Value Losses Value Losses September 30, 2025: Agency obligations $ — — 53,436 5,164 $ 53,436 5,164 Agency MBS 96 1 165,487 20,628 165,583 20,629 State and political subdivisions — — 14,610 2,346 14,610 2,346 Total $ 96 1 233,533 28,138 $ 233,629 28,139 December 31, 2024: Agency obligations $ — — 52,411 7,734 $ 52,411 7,734 Agency MBS 7 — 173,669 28,901 173,676 28,901 State and political subdivisions 1,798 17 14,776 2,884 16,574 2,901 Total $ 1,805 17 240,856 39,519 $ 242,661 39,536

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