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v3.23.1

Note 2 - Securities (Details Textual) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | 653 | 732
Debt Securities, Available-for-Sale, Unrealized Loss Position | $ 560,057,000 | $ 573,146,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss | 72,527,000 | 83,281,000
Proceeds from Sale of Debt Securities, Available-for-Sale | 0 | 0
Debt Securities, Available-for-Sale, Amortized Cost | 691,197,000 | 685,646,000
Debt Securities, Available-for-Sale | 619,973,000 | 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 | 63,400,000 |
Bonds Issued by State-based Municipalities [Member] |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss | 9,100,000 |
State of Michigan and All Its Political Subdivisions [Member] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 200,000,000 | 193,000,000
Debt Securities, Available-for-Sale | 192,000,000 | 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 | $ 227,000,000 | $ 194,000,000

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