Leases - Lease Cost and Supplemental Information (Details) - USD ($) $ in Millions |
Mar. 31, 2021 |
Dec. 31, 2020 |
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| Leases [Abstract] | ||
| Right-of-use asset | $ 9,673 | $ 10,000 |
| Lease liabilities | $ 10,275 | $ 10,474 |
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- References No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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