Receivables and Related Allowance for Credit Losses - Schedule of Equipment Installment Plan Receivables (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| EIP receivables, gross | $ 7,909 | $ 8,626 |
| Unamortized discount | (552) | (566) |
| EIP receivables, net of unamortized discount | 7,357 | 8,060 |
| Allowance for credit losses | (370) | (380) |
| EIP receivables, net of allowance for credit losses and unamortized discount | 6,987 | 7,680 |
| Balance Sheet Location [Axis]: us-gaap:NotesAndLoansReceivableNetCurrent | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| EIP receivables, net of allowance for credit losses and unamortized discount | 4,530 | 4,997 |
| Balance Sheet Location [Axis]: us-gaap:NotesAndLoansReceivableNetNoncurrent | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| EIP receivables, net of allowance for credit losses and unamortized discount | $ 2,457 | $ 2,683 |
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- Definition Financing Receivable, Before Allowance for Credit Loss, Net of Unamortized Discount No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unamortized purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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