| Cover | 12 Months Ended |
| Dec. 31, 2022 | |
| Document Information [Line Items] | |
| Document Type | DEF 14A |
| Amendment Flag | false |
| Entity Information [Line Items] | |
| Entity Registrant Name | The First of Long Island Corporation |
| Entity Central Index Key | 0000740663 |
| Pay vs Performance Disclosure | 12 Months Ended | ||
| Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | |
| Pay vs Performance Disclosure [Table] | |||
| Pay vs Performance [Table Text Block] | The following table presents information regarding compensation actually paid to the Corporation’s CEO and Non-CEO NEOs and certain performance metrics. The amount of compensation actually paid is calculated in accordance with Item 402(v) of Regulation S-K which requires disclosure of the relationship between executive pay versus the Corporation’s financial performance. Summary Compensation Table Total for CEO (1) ($) Compensation Actually Paid to CEO (1) ($) Average Summary Compensation Table Total for Non-CEO NEOs (1) ($) Average Compensation Actually Paid to Non-CEO NEOs (1) ($) Value of Initial Fixed $100 Investment Based On: Net Income (in’000) ($) Diluted Earnings per Share (Company- Selected Measure) ($) Total Shareholder Return ($) Peer Group Total Shareholder Return (2) ($) 2022 1,618,885 1,511,564 659,676 651,876 82.29 99.06 46,932 2.04 2021 914,366 1,615,231 484,497 717,930 93.50 119.74 43,089 1.81 2020 1,352,191 1,185,033 639,823 532,890 74.39 87.20 41,203 1.72 (1) Christopher Becker was the CEO in all years presented. Non-CEO NEOs for 2022 were Jay P. McConie, Christopher J. Hilton, Janet T. Verneuille and Michael J. Spolarich. Non-CEO NEOs for 2021 were Jay P. McConie, Christopher J. Hilton, Janet T. Verneuille and Susanne Pheffer. Non-CEO NEOs for 2020 were Jay P. McConie, Christopher J. Hilton, Janet T. Verneuille and Richard P. Perro. (2) Peer group is the NASDAQ U.S. Benchmark Banks Index used for purposes of Item 201(e) of Regulation S-K. | ||
| PEO Total Compensation Amount | $ 1,618,885 | $ 914,366 | $ 1,352,191 |
| PEO Actually Paid Compensation Amount | $ 1,511,564 | 1,615,231 | 1,185,033 |
| Adjustment To PEO Compensation, Footnote [Text Block] | The following is a reconciliation of Total Compensation in the Summary Compensation Table to Compensation Actually Paid for the CEO and Non-CEO NEOs. There were no valuation assumptions that differ materially from those utilized and disclosed at the time of grant. 2022 2021 2020 Compensation Actually Paid to CEO ($) Average Compensation Actually Paid to Non-CEO NEOs ($) Compensation Actually Paid to CEO ($) Average Compensation Actually Paid to Non-CEO NEOs ($) Compensation Actually Paid to CEO ($) Average Compensation Actually Paid to Non-CEO NEOs ($) Total Compensation in the Summary Compensation Table 1,618,885 659,676 914,366 484,497 1,352,191 639,823 Deduct Amounts Reported in Summary Compensation Table: Equity Awards (620,000) (161,250) — — (500,000) (137,750) Change in Defined Benefit Pension Value — (6,258) (39,605) (29,934) (108,854) (89,455) Other Additions (Deductions) to Arrive at Compensation Actually Paid: Value of awards granted in the covered year that are outstanding and unvested at year end 370,710 96,417 470,057 138,678 265,376 70,427 Change in value of awards granted in a prior year that are outstanding and unvested at year end (65,769) (20,107) 38,365 11,867 10,194 (7,125) Value of awards granted and vesting in the year 185,346 48,204 235,029 69,331 132,679 35,209 Value of awards granted in a prior year that vest in the covered year (40,154) (3,990) 27,757 34,582 (21,315) (3,859) Value of awards gained or lost in the covered year due to performance conditions 25,880 6,683 (67,263) (19,358) 24,967 6,566 Pension Service Cost 36,666 32,501 36,525 28,267 29,795 19,054 Pension Prior Service Cost — — — — — — Compensation Actually Paid 1,511,564 651,876 1,615,231 717,930 1,185,033 532,890 The Corporation’s compensation policies and practices are the responsibility of the Compensation Committee of the Board. Executive compensation is designed to balance an executive’s financial rewards with risk taken and align an executive’s compensation with the interests of shareholders. In addition to base salary, incentive compensation is provided annually to executives in the form of both equity and cash awards. Annual equity incentives vest over three years and include both performance-based and time-based awards. These awards provide incentives for decision-making that will support the long-term financial performance of the Corporation. Annual cash incentives provide further financial rewards and support the short-term financial performance of the Corporation. Total compensation paid to the CEO and each of the non-CEO NEOs takes into account certain quantitative metrics and qualitative factors as described under the heading “How We Determine The Amount to Pay for Each Element of Executive Compensation” of this proxy statement. The specific metrics and factors may vary from year-to-year in their composition or the weighting applied to each. Quantitative metrics include net income growth, ROA, ROE, diluted earnings per share growth and balance sheet growth. The quantitative metrics include both absolute metrics which measure the Corporation’s actual performance against preset targets established by the Compensation Committee and relative metrics which measure the Corporation’s actual performance against peer group results. The Corporation’s peer group is listed in this proxy statement. Qualitative metrics have included a bank safety rating and compensation committee discretion through 2021. | ||
| Non-PEO NEO Average Total Compensation Amount | $ 659,676 | 484,497 | 639,823 |
| Non-PEO NEO Average Compensation Actually Paid Amount | $ 651,876 | 717,930 | 532,890 |
| Compensation Actually Paid vs. Company Selected Measure [Text Block] | Compensation Actually Paid Versus Financial Performance Measures. Percentage Change: Increase (Decrease) Cumulative Total Shareholder Return Versus Prior Year Compensation Actually Paid to CEO ($) Average Compensation Actually Paid to Non-CEO NEOs ($) The First of Long Island Corporation (%) NASDAQ U.S. Benchmark Banks Index (%) Net Income (%) Diluted Earnings per Share (%) 2022 1,511,564 651,876 (17.7) (0.9) 8.9 12.7 2021 1,615,231 717,930 (6.5) 19.7 4.6 5.2 2020 1,185,033 532,890 (25.6) (12.8) (0.8) 3.0 The following presents executive compensation actually paid versus the percentage changes in First of Long Island Corporation ("FLIC") cumulative total shareholder return, net income and diluted earnings per share ("EPS"): The following presents cumulative total shareholder return for FLIC versus the NASDAQ U.S. Benchmark Banks Index peer group: | ||
| Tabular List [Table Text Block] | The most important financial performance measures used to link the NEO’s compensation actually paid to the Corporation’s financial performance for the most recently completed fiscal year are: Net income growth ROA ROE Diluted earnings per share growth Balance sheet growth | ||
| Total Shareholder Return Amount | $ 82.29 | 93.50 | 74.39 |
| Peer Group Total Shareholder Return Amount | 99.06 | 119.74 | 87.20 |
| Net Income (Loss) | $ 46,932,000 | $ 43,089,000 | $ 41,203,000 |
| Company Selected Measure Amount | 2.04 | 1.81 | 1.72 |
| Measure [Axis]: 1 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Net income growth | ||
| Measure [Axis]: 2 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | ROA | ||
| Measure [Axis]: 3 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | ROE | ||
| Measure [Axis]: 4 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Diluted earnings per share growth | ||
| Measure [Axis]: 5 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Balance sheet growth | ||
| Equity Awards [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ (620,000) | $ 0 | $ (500,000) |
| Change in Defined Benefit Pension Value [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 0 | (39,605) | (108,854) |
| Value of awards granted in the covered year that are outstanding and unvested at year end [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 370,710 | 470,057 | 265,376 |
| Change in value of awards granted in a prior year that are outstanding and unvested at year end [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (65,769) | 38,365 | 10,194 |
| Value of awards granted and vesting in the year [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 185,346 | 235,029 | 132,679 |
| Value of awards granted in a prior year that vest in the covered year [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (40,154) | 27,757 | (21,315) |
| Value of awards gained or lost in the covered year due to performance conditions [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 25,880 | (67,263) | 24,967 |
| Pension Service Cost [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 36,666 | 36,525 | 29,795 |
| Pension Prior Service Cost [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 0 | 0 | 0 |
| NEO Equity Awards [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (161,250) | 0 | (137,750) |
| NEO Change in Defined Benefit Pension Value [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (6,258) | (29,934) | (89,455) |
| NEO Value of awards granted in the covered year that are outstanding and unvested at year end [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 96,417 | 138,678 | 70,427 |
| NEO Change in value of awards granted in a prior year that are outstanding and unvested at year end [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (20,107) | 11,867 | (7,125) |
| NEO Value of awards granted and vesting in the year [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 48,204 | 69,331 | 35,209 |
| NEO Value of awards granted in a prior year that vest in the covered year [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (3,990) | 34,582 | (3,859) |
| NEO Value of awards gained or lost in the covered year due to performance conditions [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 6,683 | (19,358) | 6,566 |
| NEO Pension Service Cost [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 32,501 | 28,267 | 19,054 |
| NEO Pension Prior Service Cost [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ 0 | $ 0 | $ 0 |
