Intangible Assets - Narrative (Details) - U.S. Cellular $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) license
Licenses
Total winning bid \| $	$ 256
Auction 101
Licenses
Licenses won	408
Auction 102
Licenses
Licenses won	282

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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