Equity - Additional Information (Detail) - USD ($) $ in Millions |
1 Months Ended | 3 Months Ended | |
|---|---|---|---|
Apr. 30, 2018 |
Mar. 31, 2018 |
Mar. 31, 2017 |
|
| Stock repurchase program, remaining authorized repurchase amount | $ 1,860 | ||
| Number of shares repurchased | 19,000,000 | 9,000,000 | |
| Cash paid for shares repurchased | $ 1,327 | $ 420 | |
| Scenario, Forecast | |||
| Number of shares repurchased | 619,415 | ||
| Cash paid for shares repurchased | $ 45 | ||