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v3.25.0.1

Debt - Long-term Debt (Details) $ in Millions | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2024 USD ($) | Apr. 01, 2025 | Apr. 01, 2024 | Mar. 31, 2024 | Dec. 31, 2023 USD ($)
Long-term debt |  |  |  |  |
Principal amount | $ 2,923 |  |  |  | $ 3,130
Unamortized discount and debt issuance costs | 64 |  |  |  | 66
Total long-term debt | 2,859 |  |  |  | 3,064
Current portion of long-term debt | 22 |  |  |  | 20
Long-term debt, net | 2,837 |  |  |  | 3,044
Long-term debt maturities |  |  |  |  |
Scheduled principal payments 2025 | 22 |  |  |  |
Scheduled principal payments 2026 | 228 |  |  |  |
Scheduled principal payments 2027 | 158 |  |  |  |
Scheduled principal payments 2028 | 286 |  |  |  |
Scheduled principal payments 2029 | $ 5 |  |  |  |
Consolidated leverage ratio |  |  | 4.00 | 4.25 |
Consolidated interest coverage ratio | 3.00 |  |  |  |
Subsequent event |  |  |  |  |
Long-term debt maturities |  |  |  |  |
Consolidated leverage ratio |  | 3.75 |  |  |
Subordination Agreement |  |  |  |  |
Long-term debt maturities |  |  |  |  |
Consolidated funded indebtedness | $ 0 |  |  |  |
Refinancing indebtedness | $ 0 |  |  |  |
6.7% Senior Notes |  |  |  |  |
Long-term debt |  |  |  |  |
Interest rate on debt | 6.70% |  |  |  |
Principal amount | $ 544 |  |  |  | 544
Long term debt | 534 |  |  |  | 533
Unamortized discount and debt issuance costs | $ 10 |  |  |  | 11
Long-term debt maturities |  |  |  |  |
Redemption price, percentage | 100.00% |  |  |  |
6.25% Senior Notes |  |  |  |  |
Long-term debt |  |  |  |  |
Interest rate on debt | 6.25% |  |  |  |
Principal amount | $ 500 |  |  |  | 500
Long term debt | 483 |  |  |  | 483
Unamortized discount and debt issuance costs | $ 17 |  |  |  | 17
5.50% Senior Notes |  |  |  |  |
Long-term debt |  |  |  |  |
Interest rate on debt | 5.50% |  |  |  |
Principal amount | $ 500 |  |  |  | 500
Long term debt | 483 |  |  |  | 483
Unamortized discount and debt issuance costs | $ 17 |  |  |  | 17
5.50% Senior Notes |  |  |  |  |
Long-term debt |  |  |  |  |
Interest rate on debt | 5.50% |  |  |  |
Principal amount | $ 500 |  |  |  | 500
Long term debt | 484 |  |  |  | 484
Unamortized discount and debt issuance costs | $ 16 |  |  |  | 16
Callable Notes |  |  |  |  |
Long-term debt maturities |  |  |  |  |
Redemption price, percentage | 100.00% |  |  |  |
Receivables securitization agreement |  |  |  |  |
Long-term debt |  |  |  |  |
Principal amount | $ 2 |  |  |  | 150
Long term debt | 2 |  |  |  | 150
Unamortized discount and debt issuance costs | 0 |  |  |  | 0
Export credit financing agreement |  |  |  |  |
Long-term debt |  |  |  |  |
Principal amount | 150 |  |  |  | 150
Long term debt | 150 |  |  |  | 149
Unamortized discount and debt issuance costs | 0 |  |  |  | 1
Term Loan Agreements |  |  |  |  |
Long-term debt |  |  |  |  |
Principal amount | 723 |  |  |  | 783
Long term debt | 719 |  |  |  | 779
Unamortized discount and debt issuance costs | 4 |  |  |  | 4
Finance lease obligations |  |  |  |  |
Long-term debt |  |  |  |  |
Principal amount | 4 |  |  |  | 3
Unamortized discount and debt issuance costs | 0 |  |  |  | 0
Finance lease obligations | 4 |  |  |  | $ 3
Subordination Agreement | Maximum |  |  |  |  |
Long-term debt maturities |  |  |  |  |
Consolidated funded indebtedness | 105 |  |  |  |
Refinancing indebtedness | $ 250 |  |  |  |
Treasury Rate | 6.7% Senior Notes |  |  |  |  |
Long-term debt |  |  |  |  |
Contractual spread | 0.30% |  |  |  |

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Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=usm_TreasuryRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |