Fair Value of Financial Instruments - Schedule of Estimated Fair Values and Carrying Values (Detail) - USD ($) $ in Millions |
Sep. 30, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Carrying Value | $ 9,428 | $ 10,402 |
| Convertible Senior Notes [Member] | ||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Carrying Value | 3,769 | 3,729 |
| Fair Value | 27,531 | 6,110 |
| 5.30% Senior Notes due in 2025 ("2025 Notes") [Member] | ||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Carrying Value | 1,784 | 1,782 |
| Fair Value | 1,866 | 1,748 |
| Solar asset-backed notes [Member] | ||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Carrying Value | 1,119 | 1,155 |
| Fair Value | 1,132 | 1,211 |
| Solar Loan-backed Notes [Member] | ||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
| Carrying Value | 146 | 175 |
| Fair Value | $ 151 | $ 189 |