Investments - Cost Method - Additional Information (Detail) - USD ($) $ in Millions |
Mar. 31, 2016 |
Jun. 30, 2015 |
|---|---|---|
| Fair Value, Measurements, Nonrecurring | ||
| Schedule of Cost-method Investments [Line Items] | ||
| Recorded basis of common and preferred stock that are restricted for more than one year or are not publicly traded | $ 770 | $ 561 |