v3.20.2

Investments - Additional Information (Detail) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019
Debt Securities, Available-for-sale [Abstract] |  |
Contractual maturities | 36 months |
Strategic investments | $ 27 | $ 22

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