Investments and Fair Value Measurement - Change In Equity Securities (Details) - USD ($) $ in Millions |
Jun. 30, 2021 |
Dec. 31, 2020 |
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| Fair Value Disclosures [Abstract] | ||
| Initial cost basis | $ 628 | $ 6,282 |
| Upward adjustments | 0 | 1,984 |
| Downward adjustments (including impairment) | (36) | (1,690) |
| Total carrying value at the end of the period | $ 592 | $ 6,576 |
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- Definition Equity Securities Without Readily Determinable Fair Value, Cost Basis, Cumulative Amount No definition available.
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- Definition Amount of investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cumulative loss from downward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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