v3.22.0.1

Investments - Summary of Investments (Detail) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 3,214 | $ 2,872
Gross Unrealized Gains | 1 | 11
Gross Unrealized Losses | (9) | 0
Estimated Fair Value | 3,206 | 2,883
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 528 | 406
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Estimated Fair Value | 528 | 406
Corporate notes and bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,418 | 2,298
Gross Unrealized Gains | 1 | 10
Gross Unrealized Losses | (7) | 0
Estimated Fair Value | 2,412 | 2,308
Certificates of deposit |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 28 | 23
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Estimated Fair Value | 28 | 23
U.S. government and agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 140 | 145
Gross Unrealized Gains | 0 | 1
Gross Unrealized Losses | 0 | 0
Estimated Fair Value | 140 | $ 146
Mortgage and asset backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 100 |
Gross Unrealized Gains | 0 |
Gross Unrealized Losses | (2) |
Estimated Fair Value | $ 98 |

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