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v3.25.3

Debt - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jan. 31, 2025 | Dec. 31, 2024 | Jul. 31, 2024 | Jun. 30, 2024 | May 31, 2024 | Mar. 31, 2023 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | May 31, 2025 | Aug. 31, 2021
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt balance |  | $ 2,025,000,000 |  |  |  |  | $ 2,010,000,000 |  | $ 2,010,000,000 |  |  |
Interest expense related to debt instruments |  |  |  |  |  |  | 32,000,000 | $ 40,000,000 | 96,000,000 | $ 149,000,000 |  |
$330 million Revolving Credit Facility, Amended |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt balance |  | 0 |  |  |  |  | 0 |  | 0 |  |  |
Line of credit, maximum borrowing capacity |  |  |  |  |  |  | 330,000,000 |  | 330,000,000 |  | $ 330,000,000 | $ 294,000,000
Unused letters of credit |  |  |  |  |  |  | 0 |  | 0 |  |  |
Revolving credit facility, borrowings |  |  |  |  |  |  |  |  | 0 |  |  |
Periodic payment |  |  |  |  |  |  | 0 | 0 | 1,000,000 | 0 |  |
Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Increase in revolving credit facility |  |  |  |  |  | $ 300,000,000 |  |  |  |  |  |
Sixth Incremental Term Loans |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt balance |  | 2,025,000,000 |  |  |  |  | 0 |  | 0 |  |  |
Repayments of debt |  |  | $ 440,000,000 |  |  |  |  |  |  |  |  |
Face amount |  |  |  | $ 2,489,000,000 |  |  |  |  |  |  |  |
Sixth Incremental Term Loans | Alight Holdings |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, variable interest rate |  |  |  | 2.25% | 2.75% |  |  |  |  |  |  |
Seventh Incremental Term Loans |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt balance |  | $ 0 |  |  |  |  | 2,010,000,000 |  | 2,010,000,000 |  |  |
Face amount | $ 2,030,000,000 |  |  |  |  |  |  |  |  |  |  |
Seventh Incremental Term Loans | Alight Holdings |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, variable interest rate | 1.75% | 2.25% |  |  |  |  |  |  |  |  |  |
Term Loan, Amended |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Principal payment |  |  |  |  |  |  | $ 5,000,000 | $ 6,000,000 | $ 15,000,000 | $ 19,000,000 |  |

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