Employee Benefit Plans (Details) - USD ($) $ in Millions  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2023  | 
Dec. 31, 2022  | 
Dec. 31, 2021  | 
|
| Employee Benefit Plans | |||
| Employer cash contribution | $ 11 | $ 12 | $ 12 | 
| X | ||||||||||
- References No definition available. 
  | 
| X | ||||||||||
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. No definition available. 
  |