Employee Benefit Plans (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Retirement Benefits [Abstract] | |||
| Cash contributions to defined contribution plans | $ 22 | $ 18 | $ 23 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|