Property and Equipment, Net - Components of Property and Equipment, Net (Details) - USD ($) $ in Millions |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|
| Property Plant And Equipment [Line Items] | ||
| Property and equipment, gross | $ 767 | $ 742 |
| Less: accumulated depreciation | (567) | (551) |
| Total | 200 | 191 |
| Capitalized Website Development | ||
| Property Plant And Equipment [Line Items] | ||
| Property and equipment, gross | 558 | 510 |
| Total | 115 | 103 |
| Finance Lease Right-of-Use Asset | ||
| Property Plant And Equipment [Line Items] | ||
| Property and equipment, gross | 114 | 114 |
| Leasehold Improvements | ||
| Property Plant And Equipment [Line Items] | ||
| Property and equipment, gross | 24 | 37 |
| Computer Equipment and Purchased Software | ||
| Property Plant And Equipment [Line Items] | ||
| Property and equipment, gross | 56 | 64 |
| Furniture, Office Equipment and Other | ||
| Property Plant And Equipment [Line Items] | ||
| Property and equipment, gross | $ 15 | $ 17 |