Sales Of Receivables (Equipment Installment and AT&T Revolving Programs) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Equipment Installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross receivables	$ 3,725	$ 3,504
Noncurrent notes and trade receivables	1,535	1,450
Outstanding portfolio of receivables derecognized from our consolidated balance sheets	11,987	11,909
Cash proceeds received, net of remittances	9,617	8,243
Equipment Installment \| Notes receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	1,886	1,817
Equipment Installment \| Trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	304	237
Revolving
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross receivables	425	553
Noncurrent notes and trade receivables	0	0
Outstanding portfolio of receivables derecognized from our consolidated balance sheets	2,940	2,770
Cash proceeds received, net of remittances	2,940	2,770
Revolving \| Notes receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	0	0
Revolving \| Trade receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 425	$ 553

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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