Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
3 Months Ended | 12 Months Ended | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2017 |
[2] | Mar. 31, 2017 |
[2] | Dec. 31, 2016 |
[2] | Sep. 30, 2016 |
[2] | Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2017 |
Jun. 30, 2016 |
Jun. 30, 2015 |
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| Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Line Items] | ||||||||||||||||||||||||
| Net income available for common shareholders (A) | $ 6,513 | [1] | $ 4,801 | $ 5,200 | $ 4,690 | $ 3,122 | [3] | $ 3,756 | $ 5,018 | $ 4,902 | $ 21,204 | [1],[2] | $ 16,798 | [3] | $ 12,193 | |||||||||
| Weighted average outstanding shares of common stock (B) | 7,746 | 7,925 | 8,177 | |||||||||||||||||||||
| Dilutive effect of stock-based awards | 86 | 88 | 77 | |||||||||||||||||||||
| Common stock and common stock equivalents (C) | 7,832 | 8,013 | 8,254 | |||||||||||||||||||||
| Earnings Per Share | ||||||||||||||||||||||||
| Basic (A/B) | $ 0.84 | $ 0.62 | $ 0.67 | $ 0.60 | $ 0.40 | $ 0.48 | $ 0.63 | $ 0.61 | $ 2.74 | [2] | $ 2.12 | $ 1.49 | ||||||||||||
| Diluted (A/C) | $ 0.83 | [1] | $ 0.61 | $ 0.66 | $ 0.60 | $ 0.39 | [3] | $ 0.47 | $ 0.62 | $ 0.61 | $ 2.71 | [1],[2] | $ 2.10 | [3] | $ 1.48 | |||||||||
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