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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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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