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Loans and the Allowance for Credit Losses - Impairment Evaluation on Loans and Allowance for Credit Losses (Details) Details 53 false false R54.htm 995498 - Disclosure - Note 6 - Loans and the Allowance for Credit Losses - Activity in the ACL for Loans (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-6-loans-and-the-allowance-for-credit-losses-activity-in-the-acl-for-loans-details Note 6 - Loans and the Allowance for Credit Losses - Activity in the ACL for Loans (Details) Details 54 false false R55.htm 995499 - Disclosure - Note 6 - Loans and the Allowance for Credit Losses - Amortized Cost of of the Modified Loans (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-6-loans-and-the-allowance-for-credit-losses-amortized-cost-of-of-the-modified-loans-details Note 6 - Loans and the Allowance for Credit Losses - Amortized Cost of of the Modified Loans (Details) Details 55 false false R56.htm 995500 - Disclosure - Note 6 - Loans and the Allowance for Credit Losses - 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Loans and the Allowance for Credit Losses - Summary of (Reversal of) Provision for Credit Losses (Details) Details 58 false false R59.htm 995503 - Disclosure - Note 7 - Fair Value Measurements and Fair Value of Financial Instruments (Details Textual) Sheet http://www.connectonebank.com/20250331/role/statement-note-7-fair-value-measurements-and-fair-value-of-financial-instruments-details-textual Note 7 - Fair Value Measurements and Fair Value of Financial Instruments (Details Textual) Details http://www.connectonebank.com/20250331/role/statement-note-7-fair-value-measurements-and-fair-value-of-financial-instruments-tables 59 false false R60.htm 995504 - Disclosure - Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets and Liabilities Measured on a Recurring Basis (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-7-fair-value-measurements-and-fair-value-of-financial-instruments-assets-and-liabilities-measured-on-a-recurring-basis-details Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets and Liabilities Measured on a Recurring Basis (Details) Details 60 false false R61.htm 995505 - Disclosure - Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets Measured on a Nonrecurring Basis (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-7-fair-value-measurements-and-fair-value-of-financial-instruments-assets-measured-on-a-nonrecurring-basis-details Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets Measured on a Nonrecurring Basis (Details) Details 61 false false R62.htm 995506 - Disclosure - Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets Measured on Recurring Basis Using Significant Unobservable Inputs (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-7-fair-value-measurements-and-fair-value-of-financial-instruments-assets-measured-on-recurring-basis-using-significant-unobservable-inputs-details Note 7 - 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Fair Value Measurements and Fair Value of Financial Instruments - Significant Unobservable Inputs for Assets Measured on Nonrecurring Basis (Details) Details 64 false false R65.htm 995509 - Disclosure - Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Carrying Value and Fair Value of Financial Instruments (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-7-fair-value-measurements-and-fair-value-of-financial-instruments-carrying-value-and-fair-value-of-financial-instruments-details Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Carrying Value and Fair Value of Financial Instruments (Details) Details 65 false false R66.htm 995510 - Disclosure - Note 8 - Comprehensive (Loss) Income - Reclassification out of Accumulated Other Comprehensive (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-8-comprehensive-loss-income-reclassification-out-of-accumulated-other-comprehensive-details Note 8 - 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Disclosure - Note 9 - Stock-based Compensation - Activity in Restricted Shares (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-9-stockbased-compensation-activity-in-restricted-shares-details Note 9 - Stock-based Compensation - Activity in Restricted Shares (Details) Details 69 false false R70.htm 995514 - Disclosure - Note 9 - Stock-based Compensation - Summary of Unearned Performance Unit Awards (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-9-stockbased-compensation-summary-of-unearned-performance-unit-awards-details Note 9 - Stock-based Compensation - Summary of Unearned Performance Unit Awards (Details) Details 70 false false R71.htm 995515 - Disclosure - Note 9 - Stock-based Compensation - Summary of Unearned Restricted Stock Units (Details) Sheet http://www.connectonebank.com/20250331/role/statement-note-9-stockbased-compensation-summary-of-unearned-restricted-stock-units-details Note 9 - Stock-based Compensation - Summary of Unearned Restricted Stock Units (Details) Details 71 false false R72.htm 995516 - 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