Business Combinations - Schedule of Fair Value of Consideration Transferred (Details) - Ka Ena Corporation - Merger and Unit Purchase Agreement, Amendment No. 1 $ in Millions	May 01, 2024 USD ($)
Business Acquisition [Line Items]
Fair value of T-Mobile common stock issued to Ka’ena stockholders related to the adjusted upfront payment	$ 527
Fair value of cash paid to Ka’ena stockholders related to the adjusted upfront payment	396
Fair value of contingent consideration	191
Fair value of deferred consideration	27
Total fair value of consideration exchanged	$ 1,141

Business Combination, Contingent Consideration Transferred, Deferred

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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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