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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Certain Relationships and Related Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 04, 1988
TDS \| UScellular
Related Party Transaction [Line Items]
TDS ownership percentage	83.00%
TDS \| UScellular \| Minimum
Related Party Transaction [Line Items]
TDS ownership percentage				90.00%
Sidley Austin LLP
Related Party Transaction [Line Items]
Legal expense	$ 7	$ 5	$ 7
TDS
Related Party Transaction [Line Items]
Billings to UScellular from TDS	$ 87	$ 96	$ 89