Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Intangible Assets, Net

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Intangible Asset, Aggregate Purchase Price

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Intangible Asset, Expected Remaining Cost

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Number of Licenses Acquired

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Goodwill, Spectrum License Transactions and Other Intangible Assets - Narrative (Details)				1 Months Ended				3 Months Ended	12 Months Ended
	Jan. 06, 2022 license	Jul. 01, 2021 USD ($)	Apr. 01, 2020 USD ($)	Jan. 31, 2022 USD ($) license	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($) license	Oct. 31, 2020 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Goodwill [Line Items]
Goodwill from acquisition										$ 9,405,000,000
Goodwill									$ 12,188,000,000	11,117,000,000
Purchase of spectrum licenses									9,366,000,000	1,333,000,000	$ 967,000,000
Amortization expense for intangible assets									1,300,000,000	1,200,000,000	82,000,000
Licensing Agreements \| Auction 107
Goodwill [Line Items]
Number of licenses \| license						142
Aggregate purchase price						$ 9,300,000,000
Purchase of spectrum licenses						$ 8,900,000,000	$ 438,000,000
Expected remaining cost									$ 1,000,000,000
Licensing Agreements \| Auction 110
Goodwill [Line Items]
Purchase of spectrum licenses					$ 100,000,000
Licensing Agreements \| Auction 110 \| Subsequent Event
Goodwill [Line Items]
Number of licenses \| license	199			199
Aggregate purchase price				$ 2,900,000,000
Purchase of spectrum licenses								$ 2,800,000,000
Reacquired rights \| Maximum
Goodwill [Line Items]
Intangible assets, useful life									9 years
Layer3 TV
Goodwill [Line Items]
Goodwill impairment									$ 0	$ 218,000,000	$ 0
Sprint
Goodwill [Line Items]
Goodwill from acquisition			$ 9,400,000,000
Goodwill			9,423,000,000
Other intangible assets			6,280,000,000
Sprint \| Favorable lease (asset)
Goodwill [Line Items]
Finite-lived, fair value			$ 745,000,000
Weighted average useful life			18 years
Sprint \| Unfavorable spectrum leases
Goodwill [Line Items]
Finite-lived, fair value			$ 125,000,000
Weighted average useful life			19 years
Sprint \| Customer relationships
Goodwill [Line Items]
Finite-lived, fair value			$ 4,900,000,000
Weighted average useful life			8 years
Shentel
Goodwill [Line Items]
Goodwill		$ 1,035,000,000
Weighted average useful life		9 years
Other intangible assets		$ 770,000,000