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- Definition

Increase (Decrease) to Cash Tax Liability

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- Definition

Intangible Asset Acquisition, Number of Seller's Subsidiaries

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- Definition

License Purchase Agreement, Minimum Period

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No definition available.

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- Definition

Number of Federal Communications Commission (FCC) Licenses Won at Auction

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- Definition

Share Of Future Proceeds Percentage

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No definition available.

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- Definition

Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

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- Definition

Amount of contingent consideration recognized as part of consideration transferred in asset acquisition.

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- Definition

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment in the future.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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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.

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The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Spectrum License Transactions - Narrative (Details) $ in Millions						1 Months Ended		3 Months Ended		9 Months Ended		17 Months Ended
	Sep. 21, 2026 USD ($) subsidiary	Aug. 10, 2026 USD ($)	Jun. 02, 2026 USD ($)	Jan. 13, 2025 USD ($)	Sep. 12, 2023 USD ($)	Jul. 31, 2026 USD ($)	Jun. 30, 2026 USD ($) license	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Dec. 31, 2027 USD ($)	Apr. 30, 2026 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Number of FCC licenses won at auction \| license							102
Purchase of spectrum licenses								$ 324	$ 1,590	$ 834	$ 2,505
Proceeds from the sale of property, equipment and intangible assets								2,927	18	3,038	2,091
Spectrum Auction Licenses
Indefinite-lived Intangible Assets [Line Items]
Purchase of spectrum licenses						$ 253
Licensing Agreements
Indefinite-lived Intangible Assets [Line Items]
Consideration transferred			$ 46
License purchase agreement, minimum period before termination allowed					2 years
Licensing Agreements \| Spectrum Exchange Transactions
Indefinite-lived Intangible Assets [Line Items]
Gain on spectrum exchange transactions								14	0	$ 38	13
Licensing Agreements \| 800 MHz Spectrum Licenses
Indefinite-lived Intangible Assets [Line Items]
Proceeds from the sale of property, equipment and intangible assets		$ 2,900
Purchase price consideration for the assets disposed		3,600
Share of future proceeds (percent)										50.00%
Licensing Agreements \| Minimum
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration				$ 1,200	$ 1,200
Licensing Agreements \| Maximum
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration				$ 3,400	3,300
Optional Sale Licenses \| Minimum
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration					$ 2,100
Spectrum Auction Licenses
Indefinite-lived Intangible Assets [Line Items]
Consideration transferred							$ 278
Deposits assets													$ 25
Spectrum licenses
Indefinite-lived Intangible Assets [Line Items]
Purchase of spectrum licenses	$ 290
Number of seller's subsidiaries involved in the transaction \| subsidiary	2
Spectrum licenses \| Licensing Agreements \| Forecast
Indefinite-lived Intangible Assets [Line Items]
Increase our cash tax liability												$ 850
Spectrum licenses \| Licensing Agreements \| 800 MHz Spectrum Licenses
Indefinite-lived Intangible Assets [Line Items]
Purchase price consideration for the assets disposed		$ 690
Non-Cash Spectrum License Acquisitions \| Licensing Agreements \| Spectrum Exchange Transactions
Indefinite-lived Intangible Assets [Line Items]
Consideration transferred, exchange of licenses								$ 501	$ 0	$ 549	$ 173