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- Definition

Increase (Decrease) to Cash Tax Liability

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- Definition

License Purchase Agreement, Minimum Period

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- Definition

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

+ References

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- Definition

Amount of assets held-for-sale that are not part of a disposal group.

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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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- Definition

Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the capitalized costs to acquire rights under a license arrangement (for example, to sell specified products in a specified territory) having an indefinite period of benefit.

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Spectrum License Transactions - Narrative (Details) - USD ($) $ in Millions				3 Months Ended
	May 30, 2025	Jan. 13, 2025	Sep. 12, 2023	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2026	Dec. 31, 2025
Indefinite-lived Intangible Assets [Line Items]
Spectrum licenses				$ 97,564			$ 98,032
Licensing Agreements \| Spectrum Exchange Transactions
Indefinite-lived Intangible Assets [Line Items]
Spectrum licenses held-for-sale				507			$ 3
Gain on spectrum exchange transactions				2	$ 12
Licensing Agreements \| Non-Cash Spectrum License Acquisitions \| Spectrum Exchange Transactions
Indefinite-lived Intangible Assets [Line Items]
Consideration transferred, exchange of licenses				5	$ 172
Licensing Agreements \| Comcast Corporation
Indefinite-lived Intangible Assets [Line Items]
License purchase agreement, minimum period before termination allowed			2 years
Licensing Agreements \| Comcast Corporation \| Forecast \| Spectrum Licenses
Indefinite-lived Intangible Assets [Line Items]
Spectrum licenses						$ 45
Licensing Agreements \| Grain Management, LLC \| Spectrum Licenses
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration	$ 2,900
Spectrum licenses				3,600
Increase our cash tax liability	$ 850
Licensing Agreements \| Grain Management, LLC \| Spectrum Licenses \| Other current assets - of which, deferred purchase price
Indefinite-lived Intangible Assets [Line Items]
Spectrum licenses held-for-sale				2,900
Licensing Agreements \| Grain Management, LLC \| Spectrum Licenses \| Other Assets
Indefinite-lived Intangible Assets [Line Items]
Spectrum licenses held-for-sale				$ 690
Minimum \| Licensing Agreements \| Comcast Corporation
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration		$ 1,200	$ 1,200
Minimum \| Optional Sale Licenses \| Comcast Corporation
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration			2,100
Maximum \| Licensing Agreements \| Comcast Corporation
Indefinite-lived Intangible Assets [Line Items]
Total cash consideration		$ 3,400	$ 3,300