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Share-Based Payments (Tables) | 12 Months Ended
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Dec. 31, 2023
Share-Based Payment Arrangement [Abstract] |
Schedule Of Share-Based Compensation Plan Approval |
Plan | Approvals
Stock Plan | Approved effective as of May 1, 2014 by stockholders on April 23, 2014. Most recently amended and restated plan was approved effective May 2, 2018 by stockholders on May 2, 2018.
Cash Plan | Approved effective April 1, 2005 by stockholders on April 27, 2005. Most recently amended and restated plan was approved effective May 1, 2014 by stockholders on April 23, 2014.
ESPP | Approved effective July 1, 2009 by stockholders on April 29, 2009. Most recently amended and restated plan was approved effective July 1, 2021 by stockholders on April 28, 2021.
Agent Plan | Approved by stockholders on April 26, 2006. Most recently amended and restated plan was approved effective November 1, 2020 by the Salary and Employee Benefits Committee (now known as the Compensation and Human Capital Committee) of the Parent's Board on October 26, 2020.
Schedule of Types of Share-Based Payments Issued |
Plan | Types of Share-Based Payments Issued
Stock Plan | Qualified and nonqualified stock options, stock appreciation rights ("SARs"), restricted stock, restricted stock units ("RSUs"), stock grants, and other awards valued in whole or in part by reference to the Parent's common stock. The maximum exercise period for an option grant under this plan is 10 years from the date of the grant. Dividend equivalent units ("DEUs") are earned during the vesting period on RSU grants. The DEUs are reinvested in the Parent's common stock at fair value on each dividend payment date. The requisite service period for grants to employees under this plan is the lesser of: (i) the stated vested date, which is typically three years from issuance; or (ii) the date the employee becomes eligible to retire.
Cash Plan | Cash incentive units (“CIUs”). The initial dollar value of each CIU will be adjusted to reflect the percentage increase or decrease in the total shareholder return on the Parent's common stock over a specified performance period. In addition, for certain grants, the number of CIUs granted will be increased or decreased to reflect our performance on specified performance indicators compared to targeted peer companies. The requisite service period for grants under this plan is the lesser of: (i) the stated vested date, which is typically three years from issuance; or (ii) the date the employee becomes eligible to retire.
ESPP | Enables employees to purchase shares of the Parent’s common stock. The purchase price is the lower of: (i) 85% of the closing market price at the time the option is granted; or (ii) 85% of the closing price at the time the option is exercised. Shares are generally issued on June 30 and December 31 of each year.
Agent Plan | Quarterly offerings to purchase the Parent's common stock at a 10% discount with a one-year restricted period during which the shares purchased cannot be sold or transferred. Only our independent retail insurance agencies and wholesale general agencies, and certain eligible persons associated with the agencies, are eligible to participate in this plan.
Schedule of Share-Based Compensation Shares Authorized and Available for Issuance |
|  | Authorized |  | Available for Issuance |  | Awards Outstanding
Stock Plan |  | 4,750,000 |  |  | 2,318,832 |  |  | 572,249 |
ESPP |  | 5,500,000 |  |  | 1,049,788 |  |  | — |
Agent Plan |  | 3,000,000 |  |  | 1,508,712 |  |  | — |
Schedule of Share-Based Compensation Retired Plans |
Plan | Types of Share-Based Payments Issued | Reserve Shares | Awards Outstanding 1
2005 Omnibus Stock Plan ("2005 Stock Plan") | Qualified and nonqualified stock options, SARs, restricted stock, RSUs, phantom stock, stock bonuses, and other awards in such amounts and with such terms and conditions as it determined, subject to the provisions of the 2005 Stock Plan. The maximum exercise period for an option grant under this plan is 10 years from the date of the grant. DEUs are earned during the vesting period on RSU grants. The DEUs are reinvested in the Parent's common stock at fair value on each dividend payment date. | 1,951,538 |  | 26,138 |
Parent's Stock Compensation Plan for Non-employee Directors | Directors could elect to receive a portion of their annual compensation in shares of the Parent's common stock. | 37,412 |  | 37,412 |
1 Awards outstanding under the 2005 Stock Plan represent shares deferred by our non-employee directors.
Schedule of Summary of Restricted Stock Units Transactions under Share-Based Payment Plans |
|  | Number of Shares |  | Weighted Average Grant Date Fair Value
Unvested RSU awards at December 31, 2022 |  | 637,062 |  |  | $ | 68.84 |
Granted 2023 |  | 191,867 |  |  | 99.55 |
Vested 2023 |  | (230,383) |  |  | 68.54 |
Forfeited 2023 |  | (47,325) |  |  | 76.19 |
Unvested RSU awards at December 31, 2023 |  | 551,221 |  |  | $ | 79.23 |
Schedule of Share-Based Compensation ESPP and ASPP Shares Granted |
|  | 2023 |  | 2022 |  | 2021
ESPP Issuances |  | 67,075 |  |  | 67,986 |  |  | 72,239 |
Agent Plan Issuances |  | 42,786 |  |  | 56,736 |  |  | 50,999 |
Schedule of Weighted Average Assumptions for Employee Stock Purchase Plan |
|  | ESPP
|  | 2023 |  | 2022 |  | 2021
Risk-free interest rate |  | 5.14 | % |  | 1.42 |  |  | 0.07 |
Expected term |  | 6 months |  | 6 months |  | 6 months
Dividend yield |  | 1.3 | % |  | 1.3 |  |  | 1.4 |
Expected volatility |  | 26 | % |  | 21 |  |  | 28 |
Schedule of Weighted-Average Fair Value of Options and Stock Per Share |
|  | 2023 |  | 2022 |  | 2021
RSUs |  | $ | 99.55 |  |  | 76.09 |  |  | 64.03 |
ESPP: |  |  |  |  |  |
Six month option |  | 6.67 |  |  | 4.43 |  |  | 4.69 |
Discount of grant date market value |  | 13.91 |  |  | 12.61 |  |  | 10.98 |
Total ESPP |  | 20.58 |  |  | 17.04 |  |  | 15.67 |
Agent Plan: |  |  |  |  |  |
Discount of grant date market value |  | 9.99 |  |  | 8.28 |  |  | 7.57 |
Schedule of Compensation Cost for Share-based Payment Arrangements |
($ in millions) |  | 2023 |  | 2022 |  | 2021
Share-based compensation expense, pre-tax |  | $ | 23.0 |  |  | 23.6 |  |  | 22.3 |
Income tax benefit, including the benefit related to stock grants that vested during the year |  | (6.4) |  |  | (5.6) |  |  | (5.1) |
Share-based compensation expense, after-tax |  | $ | 16.6 |  |  | 18.0 |  |  | 17.2 |

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