Sales Of Receivables (Equipment Installment and AT&T Revolving Programs) (Details) - Equipment Installment - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross receivable	$ 4,309	$ 4,361
Other Assets	1,722	1,909
Outstanding portfolio of receivables derecognized from our consolidated balance sheets	10,049	9,767
Cash proceeds received, net of remittances	8,180	6,644
Notes receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	1,894	1,846
Trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 693	$ 606

The cummulative cash proceeds received, net of remittances (excluding amounts returned as deferred purchase price).

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that have been derecognized. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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