Intangible Assets - Narrative (Details) - Auction 103 - U.S. Cellular $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) license
Licenses
Licenses won \| license	237
Total winning bid	$ 146
FCC upfront payment	$ 24

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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