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v3.22.0.1

Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands |  | 1 Months Ended | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2022 USD ($) | Apr. 30, 2020 | Dec. 31, 2021 USD ($) | May 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Sep. 30, 2020 USD ($) | Aug. 08, 2020 USD ($) | Jul. 15, 2020 USD ($) | Jun. 01, 2014 USD ($)
Number of Unconsolidated Business Trusts Formed to Issue Trust Preferred Securities |  |  | 5 |  |  |  |  |  |
Loans and Leases Receivable, Deferred Income, Total |  |  | $ 2,500 |  | $ 4,400 |  |  |  |
Interest Income on Commercial and Mortgage Loans Discontinued Period (Day) |  |  | 90 days |  |  |  |  |  |
Maximum Delinquency Period for Consumer and Credit Card Loans to be Charged Off (Day) |  |  | 120 days |  |  |  |  |  |
Repossessed Assets, Total |  |  | $ 0 |  | 700 |  |  |  |
Subsequent Event [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Allowance Reduction | $ 200 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Allowance Reduction | $ 2,000 |  |  |  |  |  |  |  |
Core Deposits [Member] |  |  |  |  |  |  |  |  |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year) |  |  | 10 years |  |  |  |  |  |
Not Designated as Hedging Instrument [Member] | Mortgage Loan Derivative [Member] |  |  |  |  |  |  |  |  |
Derivative Asset, Total |  |  | $ 300 |  | 500 |  |  |  |
Commercial Loan [Member] |  |  |  |  |  |  |  |  |
Loan Participation, Amount |  |  | 24,200 |  | $ 18,100 |  |  |  |
Commercial Portfolio Segment [Member] |  |  |  |  |  |  |  |  |
Financing Receivable, Payment Deferrals, Interest-only Amendments, Period (Day) |  | 90 days |  |  |  |  |  |  |
Financing Receivable, Payment Deferrals, Principal and Interest, Period (Day) |  | 90 days |  |  |  |  |  |  |
Financing Receivable, Payment Deferrals, Interest Rate |  | 0.00% |  |  |  |  |  |  |
Financing Receivable, Number of Principal and Interest Payment Deferrals |  |  |  |  |  |  |  | 750 |
Financing Receivable, Principal and Interest Deferred Payments |  |  | $ 0 |  |  |  |  | $ 719,000 |
Retail Portfolio Segment [Member] |  |  |  |  |  |  |  |  |
Financing Receivable, Payment Deferrals, Principal and Interest, Period (Day) |  | 90 days |  |  |  |  |  |  |
Financing Receivable, Number of Principal and Interest Payment Deferrals |  |  | 8 |  |  | 260 |  |  |
Financing Receivable, Principal and Interest Deferred Payments |  |  | $ 400 |  |  | $ 23,800 |  |  |
SBA, CARES Act, Paycheck Protection Program [Member] |  |  |  |  |  |  |  |  |
Number of Loans Originated Under the Paycheck Protection Program |  |  |  |  |  |  | 2,200 |  |
Financing Receivable, before Allowance for Credit Loss, Total |  |  |  |  |  |  | $ 554,000 |  |
Financing Receivable, Not Yet Forgiven, Number of Loans |  |  | 10 |  |  |  |  |  |
Financing Receivable, Not Yet Forgiven |  |  | $ 1,300 |  |  |  |  |  |
Amortization of Deferred Loan Origination Fees, Net |  |  | 3,700 |  |  |  |  |  |
SBA, CARES Act, Paycheck Protection Program, Round Two [Member] |  |  |  |  |  |  |  |  |
Number of Loans Originated Under the Paycheck Protection Program |  |  |  | 1,200 |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  |  |  | $ 208,000 |  |  |  |  |
Amortization of Deferred Loan Origination Fees, Net |  |  | $ 7,100 |  |  |  |  |  |
Financing Receivable, Forgiveness Transactions, Number of Loans |  |  | 1,000 |  |  |  |  |  |
Financing Receivable, Forgiveness Transactions |  |  | $ 169,000 |  |  |  |  |  |
Firstbank Corporation [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total |  |  |  |  |  |  |  |  | $ 1,500,000
Business Combination Branches Acquired |  |  |  |  |  |  |  |  | 46

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