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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Commitments and Contingencies - Narrative (Details) $ in Millions				1 Months Ended	3 Months Ended			12 Months Ended		24 Months Ended
	Apr. 01, 2025 USD ($)	May 24, 2024 USD ($)	Jan. 05, 2023 customer_account	Apr. 18, 2025 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2028 USD ($)
Loss Contingencies [Line Items]
Less Than 1 Year						$ 4,575.0
1 - 3 Years						5,383.0
3 - 5 Years						2,071.0
More Than 5 Years						2,207.0
Legal settlement paid						$ 350.0
Aggregate incremental expense								$ 150.0	$ 150.0
Number of customer accounts impacted \| customer_account			37,000,000
Selling, General and Administrative Expenses
Loss Contingencies [Line Items]
Aggregate incremental expense							$ 400.0
UScellular Wireless Assets Operations \| Purchase Agreement
Loss Contingencies [Line Items]
Payments for asset acquisition		$ 4,400.0
Asset acquisition, maximum transferred liabilities incurred		$ 2,000.0
Forecast \| UScellular Wireless Assets Operations \| Purchase Agreement
Loss Contingencies [Line Items]
Estimated incremental future minimum lease payments					$ 1,400.0
Lessee leasing arrangements, operating leases, term of contract (years)					15 years
Lumos \| Forecast
Loss Contingencies [Line Items]
Expected investment to acquire interest in joint venture										$ 500.0
Metronet \| Forecast
Loss Contingencies [Line Items]
Expected investment to acquire interest in joint venture					$ 4,900.0
Ownership interest in joint venture (percent)					50.00%
Subsequent Event
Loss Contingencies [Line Items]
Expected increase to total purchase commitments				$ 1,500.0
Subsequent Event \| Lumos
Loss Contingencies [Line Items]
Expected investment to acquire interest in joint venture	$ 926.0
Ownership interest in joint venture (percent)	50.00%