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v3.23.3

Note 2 - Securities (Details Textual) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($)
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | 809 | 732
Debt Securities, Available-for-Sale, Unrealized Loss Position | $ 585,698,000 | $ 573,146,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss | 93,199,000 | 83,281,000
Proceeds from Sale of Debt Securities, Available-for-Sale | 0 | 0
Debt Securities, Available-for-Sale, Amortized Cost | 685,455,000 | 685,646,000
Debt Securities, Available-for-Sale | 592,305,000 | 602,936,000
Bonds Issued or Guaranteed by Agencies of the U.S. Federal Government [Member] |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss | 75,900,000 |
Bonds Issued by State-based Municipalities [Member] |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss | 17,300,000 |
State of Michigan and All Its Political Subdivisions [Member] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 197,000,000 | 193,000,000
Debt Securities, Available-for-Sale | 180,000,000 | 182,000,000
All Other States and Their Political Subdivisions [Member] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 0 | 0
US Government Agency Debt Obligations and Mortgage Backed Securities [Member] |  |
Debt Securities, Available-for-Sale, Restricted | 164,000,000 | 194,000,000
Deposit Liabilities, Collateral Issued, Financial Instruments | $ 96,500,000 | $ 0

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