| Pay vs Performance Disclosure | 12 Months Ended |
| Dec. 31, 2023 USD ($) $ / shares | Dec. 31, 2022 USD ($) $ / shares | Dec. 30, 2022 | Dec. 31, 2021 USD ($) $ / shares | Dec. 31, 2020 USD ($) $ / shares |
| Pay vs Performance Disclosure | | | | | |
| Pay vs Performance Disclosure, Table | Year Summary Comp. Table Total for CEO - Michael D. Peduzzi (1) ($) Summary Comp. Table Total for CEO - Joseph B. Bower, Jr. (2) ($) Comp. Actually Paid to CEO - Michael D. Peduzzi (1) ($) Comp. Actually Paid to CEO - Joseph B. Bower, Jr. (2) ($) Average Summary Comp. Table Total for Non-CEO NEOs (3) ($) Average Comp. Actually Paid to Non-CEO NEOs (3) ($) Value of Initial Fixed $100 Investment Based On: Net Income (5) ($) Fully-Diluted Earnings Per Share TSR Peer Group TSR (4) 2023 1,175,410 N/A 1,262,008 N/A 599,987 614,400 78 103 58,020 2.55 2022 1,110,489 2,432,571 1,117,076 1,612,982 628,263 625,017 79 100 63,188 3.26 2021 3,028,549 1,734,559 557,132 570,275 86 106 57,707 3.16 2020 1,608,420 1,107,862 470,922 402,368 67 77 32,743 1.97 | | | | |
| Company Selected Measure Name | Fully-diluted EPS | | | | |
| Named Executive Officers, Footnote | (1) Mr. Peduzzi was appointed President and Chief Executive Officer, effective December 31, 2022. (2) Mr. Bower retired from his position as President and Chief Executive Officer, effective December 31, 2022. (3) For fiscal year 2023 and 2022, the Corporation’s non-CEO NEOs were Tito L. Lima, Richard L. Greslick, Jr., Martin T. Griffith and Leanne D. Kassab. For fiscal years 2021 and 2020 the Corporation’s non-CEO NEOs were Tito L. Lima, Richard L. Greslick, Jr, Martin T. Griffith and Joseph E. Dell, Jr. | | | | |
| Peer Group Issuers, Footnote | The TSR peer group utilized is the same peer group disclosed in the Competitive Benchmarking section above. | | | | |
| Changed Peer Group, Footnote | The peer group used for 2023 included the addition of four banks and removal of two banks that were not in the prior year's peer group. The changes to the peer group were primarily driven by changes in peer bank asset size, with banks removed or added to create a peer group more similar in asset size to the Corporation. The peer group TSR calculated using the 2022 peer group is presented below: Year Value of Initial Fixed $100 Investment Based On: TSR 2022 Peer Group TSR 2023 78 102 2022 79 100 2021 86 106 2020 67 77 | | | | |
| Adjustment To PEO Compensation, Footnote | CEO SCT Total to CAP Reconciliation – Michael D. Peduzzi 2023 2022 SCT Total Compensation $ 1,175,410 $ 1,110,489 SCT Restricted Stock Awards (199,991) (50,001) Fair Value of New Unvested Equity Awards 316,373 55,669 Change in Fair Value of Existing Unvested Equity Awards (4,528) (6,306) Change in Fair Value of Vesting Equity Awards (3,144) (105) Dividends on Unvested Equity Awards 3,823 2,488 SCT Change in Pension Value & Nonqualified Deferred Compensation Earnings (240,157) (278,205) Service Cost & Prior Service Cost 214,222 283,047 CAP $ 1,262,008 $ 1,117,076 CEO SCT Total to CAP Reconciliation – Joseph B. Bower, Jr. 2022 2021 2020 SCT Total Compensation $ 2,432,571 $ 3,028,549 $ 1,608,420 SCT Restricted Stock Awards (261,010) (272,400) (347,079) Fair Value of New Unvested Equity Awards — 286,041 192,291 Change in Fair Value of Existing Unvested Equity Awards — 76,316 (156,339) Change in Fair Value of Vesting Equity Awards 3,631 19,005 45,515 Fair Value of New Vested Equity Awards 232,476 — — Fair Value as of Prior Year-end of Equity Awards Forfeited (258,031) — — Dividends on Unvested Equity Awards 10,706 6,933 4,842 SCT Change in Pension Value & Nonqualified Deferred Compensation Earnings (902,701) (1,760,834) (467,045) Service Cost & Prior Service Cost 355,340 350,949 227,257 CAP $ 1,612,982 $ 1,734,559 $ 1,107,862 | | | | |
| Non-PEO NEO Average Total Compensation Amount | $ 599,987 | $ 628,263 | | $ 557,132 | $ 470,922 |
| Non-PEO NEO Average Compensation Actually Paid Amount | $ 614,400 | 625,017 | | 570,275 | 402,368 |
| Adjustment to Non-PEO NEO Compensation Footnote | Average Non-CEO NEOs SCT Total to CAP Reconciliation 2023 2022 2021 2020 SCT Total Compensation $ 599,987 $ 628,263 $ 557,132 $ 470,922 SCT Restricted Stock Awards (99,953) (76,257) (66,438) (73,438) Fair Value of New Unvested Equity Awards 117,016 84,907 69,940 42,335 Change in Fair Value of Existing Unvested Equity Awards (4,721) (11,407) 15,104 (31,109) Change in Fair Value of Vesting Equity Awards (7,198) 2,085 (969) (3,771) Dividends on Unvested Equity Awards 2,399 1,971 2,000 1,766 SCT Change in Pension Value & Nonqualified Deferred Compensation Earnings (56,571) (19,987) (23,198) (17,301) Service Cost & Prior Service Cost 63,441 15,442 16,704 12,964 CAP $ 614,400 $ 625,017 $ 570,275 $ 402,368 | | | | |
| Equity Valuation Assumption Difference, Footnote | he fair value of equity awards is computed in a manner consistent with the fair value methodology used to report Outstanding Equity Awards at Fiscal Year-End. This may result in a difference in the share value input used for the fair value calculation at year-end when compared to the share value used for performance-based share awards at time of award. | | | | |
| Compensation Actually Paid vs. Total Shareholder Return | Comparison of Compensation Actually Paid versus Corporation TSR As shown in the chart below, the CAP to our President and Chief Executive Officer and the average CAP to our other Non-CEO NEOs are generally aligned with our TSR. This is primarily due to performance-based incentive compensation, which links payouts to metrics that increase shareholder value, such as fully-diluted EPS and return on equity. Mr. Peduzzi was appointed President and Chief Executive Officer of CNB Financial Corporation, effective December 31, 2022, upon Mr. Bower's retirement. Mr. Peduzzi's promotion was the primary driver of his higher CAP received in 2023 versus 2022 as a result of an increase in his base salary and restricted stock awards. | | | | |
| Compensation Actually Paid vs. Net Income | Comparison of Compensation Actually Paid versus Net Income The chart below compares the CAP to our President and Chief Executive Officer and the average of the CAP to our other Non-CEO NEOs to net income. As shown in the chart, the CAP to our President and Chief Executive Officer and average of the CAP to our other Non-CEO NEOs has increased or decreased in line with our net income. This is because net income is a direct input in the calculation of fully-diluted EPS, one of the most important measures used to link our NEOs’ (including our President and Chief Executive Officer) CAP to our performance. | | | | |
| Compensation Actually Paid vs. Company Selected Measure | Comparison of Compensation Actually Paid versus Company-Selected Measure (“CSM”) The chart below compares the CAP to our President and Chief Executive Officer’s and average of the CAP to other Non-CEO NEOs and our CSM, fully-diluted EPS, which shows a strong relationship between fully-diluted EPS and CAP. | | | | |
| Total Shareholder Return Vs Peer Group | Comparison of Corporation TSR versus Peer Group TSR As shown in the chart below, the Corporation’s TSR is less than Corporation’s peer group TSR. | | | | |
| Tabular List, Table | Fully-diluted EPS • Commercial Loan Revenues • Efficiency Ratio • Deposit Growth (excluding Time Deposits) • Wealth & Asset Management revenue • Return on Equity | | | | |
| Total Shareholder Return Amount | $ 78 | 79 | | 86 | 67 |
| Peer Group Total Shareholder Return Amount | 103 | 100 | | 106 | 77 |
| Net Income (Loss) | $ 58,020,000 | $ 63,188,000 | | $ 57,707,000 | $ 32,743,000 |
| Company Selected Measure Amount | $ / shares | 2.55 | 3.26 | | 3.16 | 1.97 |
| PEO Name | Mr. Peduzzi | | Mr. Bower | Mr. Bower | Mr. Bower |
| Additional 402(v) Disclosure | (5) Presented in thousands (6) Compensation actually paid (“CAP”) is defined by the SEC and is computed by starting with the “Total” column of the Summary Compensation Table (“SCT”) for each year and then: • subtracting the amount in the “Restricted Stock Awards” column of the SCT for such year, • adding, for all unvested equity awards granted during the reporting year and outstanding on the last day of the reporting year, the fair value as of the last day of the reporting year, utilizing the same assumptions as the Outstanding Equity Awards at 2023 Fiscal Year-End table below. • adding, for all unvested equity awards granted prior to the reporting year and outstanding on the last day of the reporting year, the change in fair value from the last day of the preceding year to the last day of the reporting year, utilizing the same assumptions as the Outstanding Equity Awards at 2023 Fiscal Year-End table below. • adding, for equity awards vesting during the reporting year, the change in fair value from the last day of the preceding year to the vesting date, • adding the value of any dividends or other earnings paid in the reporting year on unvested equity awards that are not otherwise included in the total compensation for the reporting year, • subtracting the amount in the “Change in Pension Value & Nonqualified Deferred Compensation Earnings” column of the SCT for such year, and • | | | | |
| Measure:: 1 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | Fully-diluted EPS | | | | |
| Measure:: 2 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | Commercial Loan Revenues | | | | |
| Measure:: 3 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | Efficiency Ratio | | | | |
| Measure:: 4 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | Deposit Growth (excluding Time Deposits) | | | | |
| Measure:: 5 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | Wealth & Asset Management revenue | | | | |
| Measure:: 6 | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Name | Return on Equity | | | | |
| Michael D. Peduzzi [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| PEO Total Compensation Amount | $ 1,175,410 | $ 1,110,489 | | | |
| PEO Actually Paid Compensation Amount | 1,262,008 | 1,117,076 | | | |
| Joseph B. Bower, Jr. [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| PEO Total Compensation Amount | | 2,432,571 | | $ 3,028,549 | $ 1,608,420 |
| PEO Actually Paid Compensation Amount | | 1,612,982 | | 1,734,559 | 1,107,862 |
| PEO | Michael D. Peduzzi [Member] | SCT Restricted Stock Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (199,991) | (50,001) | | | |
| PEO | Michael D. Peduzzi [Member] | Fair Value of New Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 316,373 | 55,669 | | | |
| PEO | Michael D. Peduzzi [Member] | Change in Fair Value of Existing Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (4,528) | (6,306) | | | |
| PEO | Michael D. Peduzzi [Member] | Change in Fair Value of Vesting Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (3,144) | (105) | | | |
| PEO | Michael D. Peduzzi [Member] | Dividends on Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 3,823 | 2,488 | | | |
| PEO | Michael D. Peduzzi [Member] | SCT Change in Pension Value & Nonqualified Deferred Compensation Earnings [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (240,157) | (278,205) | | | |
| PEO | Michael D. Peduzzi [Member] | Service Cost & Prior Service Cost [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 214,222 | 283,047 | | | |
| PEO | Joseph B. Bower, Jr. [Member] | SCT Restricted Stock Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | (261,010) | | (272,400) | (347,079) |
| PEO | Joseph B. Bower, Jr. [Member] | Fair Value of New Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 0 | | 286,041 | 192,291 |
| PEO | Joseph B. Bower, Jr. [Member] | Change in Fair Value of Existing Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 0 | | 76,316 | (156,339) |
| PEO | Joseph B. Bower, Jr. [Member] | Change in Fair Value of Vesting Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 3,631 | | 19,005 | 45,515 |
| PEO | Joseph B. Bower, Jr. [Member] | Dividends on Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 10,706 | | 6,933 | 4,842 |
| PEO | Joseph B. Bower, Jr. [Member] | SCT Change in Pension Value & Nonqualified Deferred Compensation Earnings [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | (902,701) | | (1,760,834) | (467,045) |
| PEO | Joseph B. Bower, Jr. [Member] | Service Cost & Prior Service Cost [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 355,340 | | 350,949 | 227,257 |
| PEO | Joseph B. Bower, Jr. [Member] | Fair Value of New Vested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | 232,476 | | 0 | 0 |
| PEO | Joseph B. Bower, Jr. [Member] | Fair Value as of Prior Year-end of Equity Awards Forfeited [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | | (258,031) | | 0 | 0 |
| Non-PEO NEO | SCT Restricted Stock Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (99,953) | (76,257) | | (66,438) | (73,438) |
| Non-PEO NEO | Fair Value of New Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 117,016 | 84,907 | | 69,940 | 42,335 |
| Non-PEO NEO | Change in Fair Value of Existing Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (4,721) | (11,407) | | 15,104 | (31,109) |
| Non-PEO NEO | Change in Fair Value of Vesting Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (7,198) | 2,085 | | (969) | (3,771) |
| Non-PEO NEO | Dividends on Unvested Equity Awards [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | 2,399 | 1,971 | | 2,000 | 1,766 |
| Non-PEO NEO | SCT Change in Pension Value & Nonqualified Deferred Compensation Earnings [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | (56,571) | (19,987) | | (23,198) | (17,301) |
| Non-PEO NEO | Service Cost & Prior Service Cost [Member] | | | | | |
| Pay vs Performance Disclosure | | | | | |
| Adjustment to Compensation, Amount | $ 63,441 | $ 15,442 | | $ 16,704 | $ 12,964 |
