The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
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- Definition

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+ References

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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Certain Relationships and Related Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	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	$ 7	$ 5
TDS
Related Party Transaction [Line Items]
Billings to UScellular from TDS	$ 71	$ 87	$ 96