Sales Of Receivables (Equipment Installment and AT&T Revolving Programs) (Details) - Equipment Installment - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross receivable	$ 4,109	$ 4,165
Other Assets	2,112	1,854
Outstanding portfolio of receivables derecognized from our consolidated balance sheets	11,221	11,030
Cash proceeds received, net of remittances	8,529	8,519
Notes receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	1,387	1,789
Trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 610	$ 522

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

No definition available.

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No definition available.

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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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