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Property, Plant and Equipment (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Property, Plant and Equipment [Line Items]      
Land $ 55 $ 54  
Buildings 519 511  
Leasehold and land improvements 1,214 1,188  
Cable and wire 1,802 1,740  
Network and switching equipment 2,361 2,348  
Cell site equipment 3,411 3,383  
Office furniture and equipment 480 508  
Other operating assets and equipment 194 187  
System development 1,387 1,523  
Work in process 319 237  
Total property, plant and equipment, gross 11,742 11,679  
Accumulated depreciation and amortization (8,318) (8,124)  
Property, plant and equipment, net 3,424 3,555  
Depreciation and amortization expense 817 820 $ 811
(Gain) loss on asset disposals, net 21 27 22
TDS Telecom Wireline      
Property, Plant and Equipment [Line Items]      
(Gain) loss on asset disposals, net $ 1 2 $ 5
TDS Telecom Wireline | Depreciation out-of-period adjustment      
Property, Plant and Equipment [Line Items]      
Out-of-period adjustment description During 2016, TDS recorded an out-of-period adjustment attributable to 2014 and 2015 related to the over-depreciation of certain assets in the Wireline segment. TDS has determined that this adjustment was not material to the prior annual periods and also was not material to 2016 results. As a result of this out-of-period adjustment, Depreciation, amortization and accretion expense decreased by $4 million in 2016. This adjustment was made in the second quarter of 2016.    
TDS Telecom Wireline | Depreciation out-of-period adjustment | Depreciation, amortization and accretion      
Property, Plant and Equipment [Line Items]      
Out-of-period adjustment   $ (4)  
Buildings | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 5 years    
Buildings | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 40 years    
Leasehold and land improvements | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 1 year    
Leasehold and land improvements | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 30 years    
Cable and wire | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 15 years    
Cable and wire | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 35 years    
Network and switching equipment | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 3 years    
Network and switching equipment | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 13 years    
Cell site equipment | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 7 years    
Cell site equipment | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 25 years    
Office furniture and equipment | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 3 years    
Office furniture and equipment | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 10 years    
Other operating assets and equipment | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 3 years    
Other operating assets and equipment | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 12 years    
System development | Minimum      
Property, Plant and Equipment [Line Items]      
Useful life 1 year    
System development | Maximum      
Property, Plant and Equipment [Line Items]      
Useful life 7 years