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Restructuring - Additional Information (Detail) - Strategic and Operational Efficiency Restructuring Program - USD ($) $ in Millions |  | 9 Months Ended | 36 Months Ended |
--- | --- | --- | --- | ---
Dec. 19, 2024 | Sep. 30, 2025 | Dec. 31, 2027 | Dec. 31, 2024
Restructuring Cost and Reserve [Line Items] |  |  |  |
Payments for restructuring |  | $ 79 |  |
Remaining restructuring liability |  | 32 |  | $ 39
Minimum | Forecast |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Payments for restructuring |  |  | $ 170 |
Minimum | Employee Severance |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and related cost, expected cost |  | 170 |  |
Minimum | Real Estate |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and related cost, expected cost |  | 10 |  |
Minimum | Accelerated Amortization Charges Of Capitalized Software Assets |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and related cost, expected cost |  | 20 |  |
Minimum | Estimated Annual Savings |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Effect on future earnings, amount | $ 250 |  |  |
Maximum | Forecast |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Payments for restructuring |  |  | $ 200 |
Maximum | Employee Severance |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and related cost, expected cost |  | 200 |  |
Maximum | Real Estate |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and related cost, expected cost |  | 20 |  |
Maximum | Accelerated Amortization Charges Of Capitalized Software Assets |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and related cost, expected cost |  | $ 30 |  |
Maximum | Estimated Annual Savings |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Effect on future earnings, amount | $ 300 |  |  |

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