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Common Stock and Earnings Per Share - Summary of Common Stock (Details) - USD ($) shares in Thousands, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Summary of Common Stock [Line Items] |  |  |
Beginning balance (in shares) | 57,200 |  |
Ending balance (in shares) | 57,600 | 57,200 |
Common Stock |  |  |
Summary of Common Stock [Line Items] |  |  |
Beginning balance (in shares) | 57,237 | 53,220 | 52,085
Employee Stock Purchase Plan (in shares) | 16 | 11 | 17
Invest Direct (in shares) | 232 | 244 | 263
Share-Based Compensation (in shares) | 76 | 82 | 73
Equity Issuance Program (in shares) |  | 3,680 | 782
Ending balance (in shares) | 57,561 | 57,237 | 53,220
Beginning balance | $ 1,781.5 | $ 1,536.7 | $ 1,460.9
Employee Stock Purchase Plan | 0.8 | 0.9 | 0.8
Invest Direct | 13.3 | 14.9 | 17.5
Share-Based Compensation | 8.1 | 5.3 | 6.5
Equity Issuance |  | 223.7 | 51.0
Ending balance | $ 1,803.7 | $ 1,781.5 | $ 1,536.7

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