Investments - Additional Information (Detail) - USD ($) $ in Billions |
Jun. 30, 2020 |
Jun. 30, 2019 |
|---|---|---|
| Investments Debt And Equity Securities [Abstract] | ||
| Equity investments without readily determinable fair values measured at cost with adjustments for observable changes in price or impairments | $ 1.4 | $ 1.2 |