Share Repurchases (Detail) - USD ($) shares in Millions, $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2016 |
|
| Share Repurchases [Line Items] | |||||||||||||||
| Shares of common stock repurchased | 99 | 170 | 294 | ||||||||||||
| Value of common stock repurchased | $ 8,600 | $ 10,283 | $ 14,800 | ||||||||||||
| Share Repurchase Program 2016 | |||||||||||||||
| Share Repurchases [Line Items] | |||||||||||||||
| Shares of common stock repurchased | 21 | 34 | 22 | 22 | 23 | 25 | |||||||||
| Value of common stock repurchased | $ 2,100 | $ 3,100 | $ 1,800 | $ 1,600 | $ 1,600 | $ 1,600 | |||||||||
| Share Repurchase Program 2013 | |||||||||||||||
| Share Repurchases [Line Items] | |||||||||||||||
| Shares of common stock repurchased | 59 | 63 | 70 | 69 | 66 | 89 | |||||||||
| Value of common stock repurchased | $ 3,533 | $ 3,550 | $ 3,600 | $ 3,600 | $ 3,600 | $ 4,000 | |||||||||