v3.20.4

Additional Financial Information (Consolidated Statements Of Cash Flows) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Cash paid (received) during the year for: |  |  |
Interest | $ 8,237 | $ 8,693 | $ 8,818
Income taxes, net of refunds | 993 | 1,421 | (354)
Additional Financial Information [Line Items] |  |  |
Spectrum acquisitions | 1,851 | 1,809 | 43,309
Spectrum Licenses |  |  |
Additional Financial Information [Line Items] |  |  |
Spectrum acquisitions | $ 1,613 | $ 1,576 | $ 521

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