v3.19.3.a.u2
Additional Financial Information (Narrative) (Details)
$ in Millions
12 Months Ended
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Jan. 31, 2020
Concentration Risk [Line Items]        
Percentage of employees represented by CWA, IBEW, or other unions 40%      
Subsequent Event [Member]        
Concentration Risk [Line Items]        
Approximate number of persons employed at a point in time       246,000
Vendor Financing Program [Member]        
Additional Financial Information [Line Items]        
Noncash Investing Activities $ 2,632 $ 2,162 $ 1,000  
Workforce Subject to Collective Bargaining Arrangements [Member]        
Concentration Risk [Line Items]        
Number of employees under contracts where union may call a work stoppage 7,000      
Workforce Subject to Collective Bargaining Arrangements [Member] | West Wireline [Member]        
Concentration Risk [Line Items]        
Number of employees under contracts where union may call a work stoppage 13,000      
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]        
Concentration Risk [Line Items]        
Relevant union contract expiration year 2020      
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] | West Wireline [Member]        
Concentration Risk [Line Items]        
Relevant union contract expiration year April 2020