Software, net (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
---|---|---|---|---|---|
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Dec. 31, 2018 |
|
Capitalized Computer Software, Net [Abstract] | |||||
Software | $ 1,184 | $ 1,184 | $ 1,101 | ||
Accumulated amortization | (914) | (914) | (816) | ||
Software, net | 270 | 270 | $ 285 | ||
Amortization expense | $ 33 | $ 42 | $ 94 | $ 123 |