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Securities (Tables)	12 Months Ended
	Dec. 31, 2023
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 December 31, 2023 Agency obligations (a) $ 331 10,339 43,209 — 53,879 — 8,195 $ 62,074 Agency MBS (a) 32 15,109 22,090 161,058 198,289 — 27,838 226,127 State and political subdivisions — — 9,691 9,051 18,742 1 2,731 21,472 Total available-for-sale $ 363 25,448 74,990 170,109 270,910 1 38,764 $ 309,673 December 31, 2022 Agency obligations (a) $ 4,935 50,746 69,936 — 125,617 — 15,826 $ 141,443 Agency MBS (a) — 7,130 27,153 183,877 218,160 — 33,146 251,306 State and political subdivisions 300 642 15,130 45,455 61,527 11 5,681 67,197 Total available-for-sale $ 5,235 58,518 112,219 229,332 405,304 11 54,653 $ 459,946 (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) loans included in Agency MBS generally have the right to prepay such loans 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 December 31, 2023: Agency obligations  $ — — 53,879 8,195 53,879 $ 8,195 Agency MBS 66 1 198,223 27,837 198,289 27,838 State and political subdivisions 793 2 14,408 2,729 15,201 2,731 Total  $ 859 3 266,510 38,761 267,369 $ 38,764 December 31, 2022: Agency obligations  $ 55,931 4,161 69,687 11,665 125,618 $ 15,826 Agency MBS 70,293 5,842 147,867 27,304 218,160 33,146 State and political subdivisions 44,777 2,176 13,043 3,505 57,820 5,681 Total  $ 171,001 12,179 230,597 42,474 401,598 $ 54,653
Schedule of Realized Gain (Loss) [Table Text Block]	(Dollars in thousands) 2023 2022 Gross realized gains $ 1 48 Gross realized losses (6,296) (36) Realized gains, net $ (6,295) 12

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Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments.

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Tabular disclosure of the proceeds from sales of available-for-sale securities and the gross realized gains and gross realized losses that have been included in earnings as a result of those sales.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

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