Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract] | ||||
| Gain (loss) from net investment hedging, net of tax | $ (8) | $ 34 | $ 3 | $ 18 |
| Gain (loss) from net investment hedging, tax (expenses) benefit | $ 2 | $ (11) | $ (1) | $ (6) |