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Share-Based Payments - Share-Based Compensation Expense by Share-Based Compensation Program (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | $ (72.9) | $ (74.1) | $ (149.0) | $ (153.0)
Subtotal | 72.9 | 76.3 | 144.3 | 157.7
Capitalized share-based compensation costs | (2.3) | (2.6) | (5.6) | (5.9)
Share-based compensation expense included in total costs and expenses | 70.6 | 73.7 | 138.7 | 151.8
Market stock units |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | 0.1 | 1.3 | 0.4 | 3.5
Time-vested restricted stock units |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | 58.3 | 59.9 | 115.6 | 121.6
Performance stock units settled in stock |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | 11.7 | 9.8 | 22.2 | 19.3
Performance stock units settled in cash |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | 0.1 | 2.2 | (2.0) | 4.7
Employee stock purchase plan |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | 1.8 | 2.1 | 6.3 | 6.8
Options |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |
Share-based compensation expense | $ 0.9 | $ 1.0 | $ 1.8 | $ 1.8

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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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