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Disclosure - Note 14 - Accumulated Other Comprehensive Income (Loss) - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-14-accumulated-other-comprehensive-income-loss-tables Note 14 - Accumulated Other Comprehensive Income (Loss) - (Tables) Tables http://www.b1bank.com/20221231/role/statement-note-14-accumulated-other-comprehensive-income-loss- 44 false false R45.htm 044 - Disclosure - Note 15 - Shareholders' Equity and Regulatory Matters - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-15-shareholders-equity-and-regulatory-matters-tables Note 15 - Shareholders' Equity and Regulatory Matters - (Tables) Tables http://www.b1bank.com/20221231/role/statement-note-15-shareholders-equity-and-regulatory-matters- 45 false false R46.htm 045 - Disclosure - Note 16 - Stock Based Compensation - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-16-stock-based-compensation-tables Note 16 - Stock Based Compensation - (Tables) Tables http://www.b1bank.com/20221231/role/statement-note-16-stock-based-compensation- 46 false false R47.htm 046 - Disclosure - Note 18 - Other Income and Expenses - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-18-other-income-and-expenses-tables Note 18 - Other Income and Expenses - (Tables) Tables http://www.b1bank.com/20221231/role/statement-note-18-other-income-and-expenses- 47 false false R48.htm 047 - Disclosure - Note 21 - Leases - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-21-leases-tables Note 21 - Leases - (Tables) Tables http://www.b1bank.com/20221231/role/statement-note-21-leases- 48 false false R49.htm 048 - Disclosure - Note 22 - Commitments - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-22-commitments-tables Note 22 - Commitments - (Tables) Tables http://www.b1bank.com/20221231/role/statement-note-22-commitments- 49 false false R50.htm 049 - Disclosure - Note 24 - Fair Value of Financial Instruments - (Tables) Sheet http://www.b1bank.com/20221231/role/statement-note-24-fair-value-of-financial-instruments-tables Note 24 - 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Loans and the Allowance for Loan Losses - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-tables 62 false false R63.htm 062 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Loans Receivable (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-loans-receivable-details Note 7 - Loans and the Allowance for Loan Losses - Loans Receivable (Details) Details 63 false false R64.htm 063 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investment in Loans Receivable (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-allowance-for-credit-losses-and-recorded-investment-in-loans-receivable-details Note 7 - Loans and the Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investment in Loans Receivable (Details) Details 64 false false R65.htm 064 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Credit Quality Indicators (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-credit-quality-indicators-details Note 7 - Loans and the Allowance for Loan Losses - Credit Quality Indicators (Details) Details 65 false false R66.htm 065 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Past Due Loans Receivable (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-past-due-loans-receivable-details Note 7 - Loans and the Allowance for Loan Losses - Past Due Loans Receivable (Details) Details 66 false false R67.htm 066 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Loan Receivables on Nonaccrual Status (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-loan-receivables-on-nonaccrual-status-details Note 7 - Loans and the Allowance for Loan Losses - Loan Receivables on Nonaccrual Status (Details) Details 67 false false R68.htm 067 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Impaired Loans (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-impaired-loans-details Note 7 - Loans and the Allowance for Loan Losses - Impaired Loans (Details) Details 68 false false R69.htm 068 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Loans Acquired (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-loans-acquired-details Note 7 - Loans and the Allowance for Loan Losses - Loans Acquired (Details) Details 69 false false R70.htm 069 - Disclosure - Note 7 - Loans and the Allowance for Loan Losses - Changes in Accretable Difference for Loans (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-7-loans-and-the-allowance-for-loan-losses-changes-in-accretable-difference-for-loans-details Note 7 - Loans and the Allowance for Loan Losses - Changes in Accretable Difference for Loans (Details) Details 70 false false R71.htm 070 - Disclosure - Note 8 - Premises and Equipment - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-8-premises-and-equipment-details-textual Note 8 - Premises and Equipment - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-8-premises-and-equipment-tables 71 false false R72.htm 071 - Disclosure - Note 8 - Premises and Equipment - Bank Premises and Equipment (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-8-premises-and-equipment-bank-premises-and-equipment-details Note 8 - Premises and Equipment - Bank Premises and Equipment (Details) Details 72 false false R73.htm 072 - Disclosure - Note 9 - Goodwill and Other Intangible Assets - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-9-goodwill-and-other-intangible-assets-details-textual Note 9 - Goodwill and Other Intangible Assets - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-9-goodwill-and-other-intangible-assets-tables 73 false false R74.htm 073 - Disclosure - Note 9 - Goodwill and Other Intangible Assets - Summary of Core Deposit Intangible Asset (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-9-goodwill-and-other-intangible-assets-summary-of-core-deposit-intangible-asset-details Note 9 - Goodwill and Other Intangible Assets - Summary of Core Deposit Intangible Asset (Details) Details 74 false false R75.htm 074 - Disclosure - Note 9 - Goodwill and Other Intangible Assets - Estimated Aggregate Amortization Expense (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-9-goodwill-and-other-intangible-assets-estimated-aggregate-amortization-expense-details Note 9 - Goodwill and Other Intangible Assets - Estimated Aggregate Amortization Expense (Details) Details 75 false false R76.htm 075 - Disclosure - Note 10 - Deposits - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-10-deposits-details-textual Note 10 - Deposits - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-10-deposits-tables 76 false false R77.htm 076 - Disclosure - Note 10 - Deposits - Summary of Deposit Accounts (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-10-deposits-summary-of-deposit-accounts-details Note 10 - Deposits - Summary of Deposit Accounts (Details) Details 77 false false R78.htm 077 - Disclosure - Note 11 - Borrowings - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-11-borrowings-details-textual Note 11 - Borrowings - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-11-borrowings- 78 false false R79.htm 078 - Disclosure - Note 12 - Securities Sold Under Agreements to Repurchase - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-12-securities-sold-under-agreements-to-repurchase-details-textual Note 12 - Securities Sold Under Agreements to Repurchase - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-12-securities-sold-under-agreements-to-repurchase- 79 false false R80.htm 079 - Disclosure - Note 13 - Income Taxes - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-13-income-taxes-details-textual Note 13 - Income Taxes - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-13-income-taxes-tables 80 false false R81.htm 080 - Disclosure - Note 13 - Income Taxes - Provision (Credit) for Income Taxes (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-13-income-taxes-provision-credit-for-income-taxes-details Note 13 - Income Taxes - Provision (Credit) for Income Taxes (Details) Details 81 false false R82.htm 081 - Disclosure - Note 13 - Income Taxes - Reconciliation Between Statutory Federal Income Tax Rate and Effective Income Tax Rate (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-13-income-taxes-reconciliation-between-statutory-federal-income-tax-rate-and-effective-income-tax-rate-details Note 13 - Income Taxes - Reconciliation Between Statutory Federal Income Tax Rate and Effective Income Tax Rate (Details) Details 82 false false R83.htm 082 - 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Stock Based Compensation - Restricted Stock Award Activity (Details) Details 88 false false R89.htm 088 - Disclosure - Note 16 - Stock Based Compensation - Summary of Stock Option Activity (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-16-stock-based-compensation-summary-of-stock-option-activity-details Note 16 - Stock Based Compensation - Summary of Stock Option Activity (Details) Details 89 false false R90.htm 089 - Disclosure - Note 17 - Employee Benefit Plans - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-17-employee-benefit-plans-details-textual Note 17 - Employee Benefit Plans - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-17-employee-benefit-plans- 90 false false R91.htm 090 - Disclosure - Note 18 - Other Income and Expenses - Schedule of Other Income (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-18-other-income-and-expenses-schedule-of-other-income-details Note 18 - Other Income and Expenses - Schedule of Other Income (Details) Details 91 false false R92.htm 091 - Disclosure - Note 18 - Other Income and Expenses - Schedule of Other Expenses (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-18-other-income-and-expenses-schedule-of-other-expenses-details Note 18 - Other Income and Expenses - Schedule of Other Expenses (Details) Details 92 false false R93.htm 092 - Disclosure - Note 19 - Financial Instruments With Off-balance-sheet Risk - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-19-financial-instruments-with-offbalancesheet-risk-details-textual Note 19 - Financial Instruments With Off-balance-sheet Risk - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-19-financial-instruments-with-offbalancesheet-risk- 93 false false R94.htm 093 - Disclosure - Note 20 - Concentrations of Credit - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-20-concentrations-of-credit-details-textual Note 20 - 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Disclosure - Note 22 - Commitments - Funds Lent to Small Business Borrowers (Details) Sheet http://www.b1bank.com/20221231/role/statement-note-22-commitments-funds-lent-to-small-business-borrowers-details Note 22 - Commitments - Funds Lent to Small Business Borrowers (Details) Details 98 false false R99.htm 098 - Disclosure - Note 23 - Related Party Transactions - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-23-related-party-transactions-details-textual Note 23 - Related Party Transactions - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-23-related-party-transactions- 99 false false R100.htm 099 - Disclosure - Note 24 - Fair Value of Financial Instruments - (Details Textual) Sheet http://www.b1bank.com/20221231/role/statement-note-24-fair-value-of-financial-instruments-details-textual Note 24 - Fair Value of Financial Instruments - (Details Textual) Details http://www.b1bank.com/20221231/role/statement-note-24-fair-value-of-financial-instruments-tables 100 false false R101.htm 100 - 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