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v3.20.4

Summary of Significant Accounting Policies and Recent Accounting Pronouncements - Narrative (Details) connection in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) segment unit connection asset_group | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | May 04, 1988
Basis of presentation |  |  |  |
Number of connections | connection | 5.0 |  |  |
Number of reportable segments | segment | 1 |  |  |
FCC Licenses, period of renewal | 12 years |  |  |
FCC Licenses, number of accounting units | unit | 8 |  |  |
FCC Licenses, number of accounting units, built licenses | unit | 1 |  |  |
FCC Licenses, number of accounting units, unbuilt licenses | unit | 7 |  |  |
Asset groups | asset_group | 1 |  |  |
Agent liability | $ 55,000,000 | $ 59,000,000 |  |
Advertising costs | 196,000,000 | 212,000,000 | $ 215,000,000 |
Amortization of implementation costs | $ 11,000,000 |  |  |
Minimum |  |  |  |
Basis of presentation |  |  |  |
FCC Licenses, period of renewal | 10 years |  |  |
Amortization period | 3 years |  |  |
Maximum |  |  |  |
Basis of presentation |  |  |  |
FCC Licenses, period of renewal | 15 years |  |  |
Amortization period | 5 years |  |  |
Leasehold and land improvements | Minimum |  |  |  |
Basis of presentation |  |  |  |
Useful life | 1 year |  |  |
Leasehold and land improvements | Maximum |  |  |  |
Basis of presentation |  |  |  |
Useful life | 30 years |  |  |
Pension |  |  |  |
Basis of presentation |  |  |  |
Defined contribution cost | $ 12,000,000 | 11,000,000 | 11,000,000 |
401(k) |  |  |  |
Basis of presentation |  |  |  |
Defined contribution cost | 15,000,000 | 14,000,000 | $ 15,000,000 |
TDS |  |  |  |
Basis of presentation |  |  |  |
Income taxes receivable | 125,000,000 | 46,000,000 |  |
Licenses |  |  |  |
Basis of presentation |  |  |  |
Impairment of intangible assets | $ 0 | $ 0 |  |
UScellular | TDS |  |  |  |
Basis of presentation |  |  |  |
TDS ownership of UScellular | 82.00% |  |  |
UScellular | TDS | Minimum |  |  |  |
Basis of presentation |  |  |  |
TDS ownership of UScellular |  |  |  | 90.00%

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