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Pay vs Performance Disclosure | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Pay vs Performance Disclosure |  |  |  |
Pay vs Performance Disclosure, Table |
Year (a) | ​ | ​ | Summary Compensation Table Total for PEO (b) | ​ | ​ | Compensation Actually Paid to PEO (c) | ​ | ​ | Average Summary Compensation Table Total for Non-PEO NEOs (d) | ​ | ​ | Average Compensation Actually Paid to Non-PEO NEOs (e) | ​ | ​ | Value of Initial Fixed $100 Investment Based On: | ​ | ​ | Net Income (h) | ​ | ​ | CI (i) | ​
​ | Total Shareholder Return (f) | ​ | ​ | Peer Group Total Shareholder Return (g) | ​
2023 | ​ | ​ | ​ | $ | 16,084,212 | ​ | ​ | ​ | ​ | $ | 17,516,540 | ​ | ​ | ​ | ​ | $ | 4,912,166 | ​ | ​ | ​ | ​ | $ | 5,374,060 | ​ | ​ | ​ | ​ | $ | 125 | ​ | ​ | ​ | ​ | $ | 169 | ​ | ​ | ​ | ​ | $ | 1,205,000,000 | ​ | ​ | ​ | ​ | $ | 1,312,000,000 | ​ | ​
2022 | ​ | ​ | ​ | $ | 15,068,389 | ​ | ​ | ​ | ​ | $ | 14,945,719 | ​ | ​ | ​ | ​ | $ | 4,081,690 | ​ | ​ | ​ | ​ | $ | 3,537,640 | ​ | ​ | ​ | ​ | $ | 118 | ​ | ​ | ​ | ​ | $ | 156 | ​ | ​ | ​ | ​ | $ | 682,000,000 | ​ | ​ | ​ | ​ | $ | 1,201,000,000 | ​ | ​
2021 | ​ | ​ | ​ | $ | 14,246,207 | ​ | ​ | ​ | ​ | $ | 16,180,923 | ​ | ​ | ​ | ​ | $ | 3,571,966 | ​ | ​ | ​ | ​ | $ | 3,965,857 | ​ | ​ | ​ | ​ | $ | 113 | ​ | ​ | ​ | ​ | $ | 130 | ​ | ​ | ​ | ​ | $ | 1,184,000,000 | ​ | ​ | ​ | ​ | $ | 1,083,000,000 | ​ | ​
2020 | ​ | ​ | ​ | $ | 11,469,174 | ​ | ​ | ​ | ​ | $ | 9,870,731 | ​ | ​ | ​ | ​ | $ | 4,009,419 | ​ | ​ | ​ | ​ | $ | 3,854,688 | ​ | ​ | ​ | ​ | $ | 95 | ​ | ​ | ​ | ​ | $ | 107 | ​ | ​ | ​ | ​ | $ | 690,000,000 | ​ | ​ | ​ | ​ | $ | 1,049,000,000 | ​ | ​
​ (a) The Pay Versus Performance table includes four years of information. Future disclosures will contain information until a rolling five year period is established. ​ (b) Our Principal Executive Officer (PEO) for each of the years reported was Dino Robusto. The amounts reported are the amounts of total compensation reported in our Summary Compensation Table for PEO Dino Robusto. ​ (c) The amounts reported are the amount of “compensation actually paid”, as computed in accordance with SEC rules. The amounts do not reflect the actual amount of compensation earned or realized by or paid to our PEO or non-PEO NEOs during the applicable year. In accordance with SEC rules, adjustments were made to Total Compensation reported in our Summary Compensation Table to determine the compensation actually paid. Adjustments made are included in the table below footnotes. ​ (d)(e) Included in the average Summary Compensation Table total and average compensation actually paid to non-PEO NEOs for 2023 are Messrs. Scott R. Lindquist, Douglas M. Worman,, Daniel P. Franzetti, and Ms. Susan A. Stone. For 2022 the non-PEO NEOs included are Messrs. Larry A. Haefner, Scott R. Lindquist, Douglas M. Worman, Gerald S. Haase, Daniel P. Franzetti, and Kevin G. Smith. For 2021 the non-PEO NEOs included are Messrs. Larry A. Haefner, Albert J. Miralles, Douglas M.Worman, Kevin J. Leidwinger, and Kevin G. Smith. For 2020 the non-PEO NEOs included are Messrs. James Anderson, Larry A. Haefner, Douglas M. Worman, Kevin J. Leidwinger, and Kevin G. Smith. ​ (f) Cumulative Total Shareholder Return (TSR) is calculated by dividing the sum of the cumulative amount of dividends for the measurement period, assuming dividend reinvestment, and the difference between the Company’s share price at the end of each applicable fiscal year and the beginning of the measurement period by the Company’s share price at the beginning of the measurement period (December 31, 2019). TSR for the Company is presented using the value of an initial $100 investment at beginning of December 31, 2019. ​ (g) The peer group companies for TSR in the table above are the nine companies listed on page 25 of this proxy statement. The same peer group has been used for all years disclosed. Peer group TSR disclosure in the table is required to be market capitalization weighted. ​ (h) As of January 1, 2023, the Company adopted Accounting Standards Update (ASU) 2018-12, Financial Services-Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts which uses the modified retrospective method applied as of the transition date of January 1, 2021. Accordingly, Net Income for years 2022 and 2021 reflect the application of the new guidance. Prior to such application, Net Income for years 2022 and 2021 was $894,000,000 and $1,202,000,000, respectively. ​ (i) CI as defined under “Executive Compensation-Performance Measures” in this proxy statement (pages 21-23). ​
Year | ​ | ​ | Reported Summary Compensation Table Total for PEO (a) | ​ | ​ | Equity Award Adjustments (b) | ​ | ​ | Dividends not included in SCT | ​ | ​ | Change in PV of Defined Benefit or Pension Plan | ​ | ​ | Aggregate service costs for Defined Benefit or Pension Plan | ​ | ​ | “Compensation Actually Paid” to PEO | ​
2023 | ​ | ​ | ​ | $ | 16,084,212 | ​ | ​ | ​ | ​ | $ | 1,432,327 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 17,516,540 | ​ | ​
2022 | ​ | ​ | ​ | $ | 15,068,389 | ​ | ​ | ​ | ​ | $ | (122,670) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 14,945,719 | ​ | ​
2021 | ​ | ​ | ​ | $ | 14,246,207 | ​ | ​ | ​ | ​ | $ | 1,934,716 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 16,180,923 | ​ | ​
2020 | ​ | ​ | ​ | $ | 11,469,174 | ​ | ​ | ​ | ​ | $ | (1,598,443) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 9,870,731 | ​ | ​
Year | ​ | ​ | Reported Average Summary Compensation Table Total for Non-PEO NEOs (a) | ​ | ​ | Equity Award Adjustments (b) | ​ | ​ | Dividends not included in SCT | ​ | ​ | Change in PV of Defined Benefit or Pension Plan | ​ | ​ | Aggregate service costs for Defined Benefit or Pension Plan | ​ | ​ | “Compensation Actually Paid” to Non-PEO NEOs | ​
2023 | ​ | ​ | ​ | $ | 4,912,166 | ​ | ​ | ​ | ​ | $ | 461,893 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 5,374,060 | ​ | ​
2022 | ​ | ​ | ​ | $ | 4,081,690 | ​ | ​ | ​ | ​ | $ | (544,050) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,537,640 | ​ | ​
2021 | ​ | ​ | ​ | $ | 3,571,966 | ​ | ​ | ​ | ​ | $ | 393,891 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,965,857 | ​ | ​
2020 | ​ | ​ | ​ | $ | 4,009,419 | ​ | ​ | ​ | ​ | $ | (154,731) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,854,688 | ​ | ​
​ (a) The Reported Summary Compensation Total for PEO and Non-PEO NEOs includes the grant date fair value of equity awards reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. ​ (b) In accordance with SEC rules for CAP calculations, instead of grant date fair value, CAP tracks the value of the equity at the start of the year to the value at the end of the year or at vesting during the year, if earlier. Equity Award Adjustments reported represent the Change in Fair Value of equity awards granted during the fiscal year and equity awards granted in prior fiscal years, which are outstanding and unvested at year end, vested during the year, or forfeited. |  |  |
Company Selected Measure Name | CI |  |  |
Named Executive Officers, Footnote | (b) Our Principal Executive Officer (PEO) for each of the years reported was Dino Robusto. The amounts reported are the amounts of total compensation reported in our Summary Compensation Table for PEO Dino Robusto. ​ (c) The amounts reported are the amount of “compensation actually paid”, as computed in accordance with SEC rules. The amounts do not reflect the actual amount of compensation earned or realized by or paid to our PEO or non-PEO NEOs during the applicable year. In accordance with SEC rules, adjustments were made to Total Compensation reported in our Summary Compensation Table to determine the compensation actually paid. Adjustments made are included in the table below footnotes. ​ (d)(e) Included in the average Summary Compensation Table total and average compensation actually paid to non-PEO NEOs for 2023 are Messrs. Scott R. Lindquist, Douglas M. Worman,, Daniel P. Franzetti, and Ms. Susan A. Stone. For 2022 the non-PEO NEOs included are Messrs. Larry A. Haefner, Scott R. Lindquist, Douglas M. Worman, Gerald S. Haase, Daniel P. Franzetti, and Kevin G. Smith. For 2021 the non-PEO NEOs included are Messrs. Larry A. Haefner, Albert J. Miralles, Douglas M.Worman, Kevin J. Leidwinger, and Kevin G. Smith. For 2020 the non-PEO NEOs included are Messrs. James Anderson, Larry A. Haefner, Douglas M. Worman, Kevin J. Leidwinger, and Kevin G. Smith. |  |  |
Peer Group Issuers, Footnote | (f) Cumulative Total Shareholder Return (TSR) is calculated by dividing the sum of the cumulative amount of dividends for the measurement period, assuming dividend reinvestment, and the difference between the Company’s share price at the end of each applicable fiscal year and the beginning of the measurement period by the Company’s share price at the beginning of the measurement period (December 31, 2019). TSR for the Company is presented using the value of an initial $100 investment at beginning of December 31, 2019. ​ (g) The peer group companies for TSR in the table above are the nine companies listed on page 25 of this proxy statement. The same peer group has been used for all years disclosed. Peer group TSR disclosure in the table is required to be market capitalization weighted. |  |  |
PEO Total Compensation Amount | $ 16,084,212 | $ 15,068,389 | $ 14,246,207 | $ 11,469,174
PEO Actually Paid Compensation Amount | $ 17,516,540 | 14,945,719 | 16,180,923 | 9,870,731
Adjustment To PEO Compensation, Footnote |
Year | ​ | ​ | Reported Summary Compensation Table Total for PEO (a) | ​ | ​ | Equity Award Adjustments (b) | ​ | ​ | Dividends not included in SCT | ​ | ​ | Change in PV of Defined Benefit or Pension Plan | ​ | ​ | Aggregate service costs for Defined Benefit or Pension Plan | ​ | ​ | “Compensation Actually Paid” to PEO | ​
2023 | ​ | ​ | ​ | $ | 16,084,212 | ​ | ​ | ​ | ​ | $ | 1,432,327 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 17,516,540 | ​ | ​
2022 | ​ | ​ | ​ | $ | 15,068,389 | ​ | ​ | ​ | ​ | $ | (122,670) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 14,945,719 | ​ | ​
2021 | ​ | ​ | ​ | $ | 14,246,207 | ​ | ​ | ​ | ​ | $ | 1,934,716 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 16,180,923 | ​ | ​
2020 | ​ | ​ | ​ | $ | 11,469,174 | ​ | ​ | ​ | ​ | $ | (1,598,443) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 9,870,731 | ​ | ​
Year | ​ | ​ | Reported Average Summary Compensation Table Total for Non-PEO NEOs (a) | ​ | ​ | Equity Award Adjustments (b) | ​ | ​ | Dividends not included in SCT | ​ | ​ | Change in PV of Defined Benefit or Pension Plan | ​ | ​ | Aggregate service costs for Defined Benefit or Pension Plan | ​ | ​ | “Compensation Actually Paid” to Non-PEO NEOs | ​
2023 | ​ | ​ | ​ | $ | 4,912,166 | ​ | ​ | ​ | ​ | $ | 461,893 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 5,374,060 | ​ | ​
2022 | ​ | ​ | ​ | $ | 4,081,690 | ​ | ​ | ​ | ​ | $ | (544,050) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,537,640 | ​ | ​
2021 | ​ | ​ | ​ | $ | 3,571,966 | ​ | ​ | ​ | ​ | $ | 393,891 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,965,857 | ​ | ​
2020 | ​ | ​ | ​ | $ | 4,009,419 | ​ | ​ | ​ | ​ | $ | (154,731) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,854,688 | ​ | ​
​ (a) The Reported Summary Compensation Total for PEO and Non-PEO NEOs includes the grant date fair value of equity awards reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. ​ (b) In accordance with SEC rules for CAP calculations, instead of grant date fair value, CAP tracks the value of the equity at the start of the year to the value at the end of the year or at vesting during the year, if earlier. Equity Award Adjustments reported represent the Change in Fair Value of equity awards granted during the fiscal year and equity awards granted in prior fiscal years, which are outstanding and unvested at year end, vested during the year, or forfeited. |  |  |
Non-PEO NEO Average Total Compensation Amount | $ 4,912,166 | 4,081,690 | 3,571,966 | 4,009,419
Non-PEO NEO Average Compensation Actually Paid Amount | $ 5,374,060 | 3,537,640 | 3,965,857 | 3,854,688
Adjustment to Non-PEO NEO Compensation Footnote |
Year | ​ | ​ | Reported Summary Compensation Table Total for PEO (a) | ​ | ​ | Equity Award Adjustments (b) | ​ | ​ | Dividends not included in SCT | ​ | ​ | Change in PV of Defined Benefit or Pension Plan | ​ | ​ | Aggregate service costs for Defined Benefit or Pension Plan | ​ | ​ | “Compensation Actually Paid” to PEO | ​
2023 | ​ | ​ | ​ | $ | 16,084,212 | ​ | ​ | ​ | ​ | $ | 1,432,327 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 17,516,540 | ​ | ​
2022 | ​ | ​ | ​ | $ | 15,068,389 | ​ | ​ | ​ | ​ | $ | (122,670) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 14,945,719 | ​ | ​
2021 | ​ | ​ | ​ | $ | 14,246,207 | ​ | ​ | ​ | ​ | $ | 1,934,716 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 16,180,923 | ​ | ​
2020 | ​ | ​ | ​ | $ | 11,469,174 | ​ | ​ | ​ | ​ | $ | (1,598,443) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 9,870,731 | ​ | ​
Year | ​ | ​ | Reported Average Summary Compensation Table Total for Non-PEO NEOs (a) | ​ | ​ | Equity Award Adjustments (b) | ​ | ​ | Dividends not included in SCT | ​ | ​ | Change in PV of Defined Benefit or Pension Plan | ​ | ​ | Aggregate service costs for Defined Benefit or Pension Plan | ​ | ​ | “Compensation Actually Paid” to Non-PEO NEOs | ​
2023 | ​ | ​ | ​ | $ | 4,912,166 | ​ | ​ | ​ | ​ | $ | 461,893 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 5,374,060 | ​ | ​
2022 | ​ | ​ | ​ | $ | 4,081,690 | ​ | ​ | ​ | ​ | $ | (544,050) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,537,640 | ​ | ​
2021 | ​ | ​ | ​ | $ | 3,571,966 | ​ | ​ | ​ | ​ | $ | 393,891 | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,965,857 | ​ | ​
2020 | ​ | ​ | ​ | $ | 4,009,419 | ​ | ​ | ​ | ​ | $ | (154,731) | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | ​ | — | ​ | ​ | ​ | ​ | $ | 3,854,688 | ​ | ​
​ (a) The Reported Summary Compensation Total for PEO and Non-PEO NEOs includes the grant date fair value of equity awards reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. ​ (b) In accordance with SEC rules for CAP calculations, instead of grant date fair value, CAP tracks the value of the equity at the start of the year to the value at the end of the year or at vesting during the year, if earlier. Equity Award Adjustments reported represent the Change in Fair Value of equity awards granted during the fiscal year and equity awards granted in prior fiscal years, which are outstanding and unvested at year end, vested during the year, or forfeited. |  |  |
Compensation Actually Paid vs. Total Shareholder Return | “Compensation Actually Paid” versus Company Total Shareholder Return (“TSR”) |  |  |
Compensation Actually Paid vs. Net Income | “Compensation Actually Paid” versus Net Income and CI Like many companies, our earnings in 2020 were significantly adversely affected by the COVID-19 pandemic. In 2021, our net income was positively impacted by strong investment gains across our investment portfolio, as well as increased rate growth, which drove increased underwriting gains. In 2022, strong performance in both P&C combined ratio and P&C underwriting premium offset decreased investment performance. In 2023, the Company had record Net Income, which included record high underwriting income and higher investment income. In each year, the CI, calculated as described herein, provided for a performance measure focused on core P&C operating results by the Company, with “compensation actually paid” generally aligning to the trend in CI in each such year, as reflected in the chart below. |  |  |
Compensation Actually Paid vs. Company Selected Measure | “Compensation Actually Paid” versus Net Income and CI Like many companies, our earnings in 2020 were significantly adversely affected by the COVID-19 pandemic. In 2021, our net income was positively impacted by strong investment gains across our investment portfolio, as well as increased rate growth, which drove increased underwriting gains. In 2022, strong performance in both P&C combined ratio and P&C underwriting premium offset decreased investment performance. In 2023, the Company had record Net Income, which included record high underwriting income and higher investment income. In each year, the CI, calculated as described herein, provided for a performance measure focused on core P&C operating results by the Company, with “compensation actually paid” generally aligning to the trend in CI in each such year, as reflected in the chart below. |  |  |
Total Shareholder Return Vs Peer Group | Company TSR versus Peer Group TSR |  |  |
Tabular List, Table | Financial Performance Measures The most important financial performance measures used by the Company to link executive “compensation actually paid” to the Company’s NEOs in 2023 to the Company’s performance are listed below.
​ | ​ | CI | ​ | ​
​ | ​ | Underlying Property & Casualty Combined Ratio | ​ | ​
​ | ​ | Property & Casualty Underwriting Premium | ​ | ​
As described under “Executive Compensation-Performance Measures” in this proxy statement (pages 21-23), CI is the Company performance measure which is the primary basis for determination of incentive compensation to executives. Further, as the determined formula for CI, as described on page 21, adjusts for certain non-core operational impact (eg, long-term care reserve changes, catastrophes under or over plan assumptions, limited partnership and common equity investment income under or over plan assumptions), the primary drivers of increased CI (and thus, increased Company performance) are underlying P&C combined ratio and P&C underwriting premium. |  |  |
Total Shareholder Return Amount | $ 125 | 118 | 113 | 95
Peer Group Total Shareholder Return Amount | 169 | 156 | 130 | 107
Net Income (Loss) | $ 1,205,000,000 | $ 682,000,000 | $ 1,184,000,000 | $ 690,000,000
Company Selected Measure Amount | 1,312,000,000 | 1,201,000,000 | 1,083,000,000 | 1,049,000,000
PEO Name | Dino Robusto |  |  |
Net Income Loss Before Application Of New Accounting Standard Update |  | $ 894,000,000 | $ 1,202,000,000 |
Measure:: 1 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | CI |  |  |
Non-GAAP Measure Description | (h) As of January 1, 2023, the Company adopted Accounting Standards Update (ASU) 2018-12, Financial Services-Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts which uses the modified retrospective method applied as of the transition date of January 1, 2021. Accordingly, Net Income for years 2022 and 2021 reflect the application of the new guidance. Prior to such application, Net Income for years 2022 and 2021 was $894,000,000 and $1,202,000,000, respectively. ​ (i) CI as defined under “Executive Compensation-Performance Measures” in this proxy statement (pages 21-23). |  |  |
Measure:: 2 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Underlying Property & Casualty Combined Ratio |  |  |
Measure:: 3 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Property & Casualty Underwriting Premium |  |  |
PEO | Total Equity Awards Adjustments [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | $ 1,432,327 | (122,670) | 1,934,716 | $ (1,598,443)
PEO | Dividends Or Other Earnings Paid On Equity Awards Not Otherwise Reflected In Fair Value [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
PEO | Total Pension Adjustments [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
PEO | Pension Adjustments Service Cost [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO | Total Equity Awards Adjustments [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 461,893 | (544,050) | 393,891 | (154,731)
Non-PEO NEO | Dividends Or Other Earnings Paid On Equity Awards Not Otherwise Reflected In Fair Value [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO | Total Pension Adjustments [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO | Pension Adjustments Service Cost [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |

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