v3.7.0.1
Acquisitions and Divestitures - Additional Information (Detail)
$ / shares in Units, $ in Millions
 1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended 14 Months Ended
Jun. 13, 2017
USD ($)
May 11, 2017
USD ($)
$ / shares
Feb. 20, 2017
USD ($)
Feb. 01, 2017
USD ($)
Dec. 06, 2016
USD ($)
Site
Jul. 23, 2016
USD ($)
May 31, 2017
USD ($)
Apr. 30, 2017
USD ($)
Jun. 30, 2017
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
Brand
People
Jun. 30, 2016
USD ($)
Dec. 31, 2015
USD ($)
Feb. 28, 2017
USD ($)
May 01, 2017
USD ($)
Business Acquisition [Line Items]                              
Goodwill                     $ 1,324        
Proceeds from dispositions of businesses                     3,512 $ 9,882      
Operating Revenues                 $ 30,548 $ 30,532 60,362 62,703      
Operating income                 8,232 4,554 15,413 12,496      
Pre-tax gain on sale of business                 1,774 1,007 $ 1,774 1,007      
Oath                              
Business Acquisition [Line Items]                              
Number of media and technology brands owned | Brand                     50        
Number of people engaged | People                     1,000,000,000        
Advanced Wireless Services Spectrum Licenses                              
Business Acquisition [Line Items]                              
Pre-tax gain on sale of wireless licenses                     $ 126 142      
Acquisitions                     1,000        
Personal Communication Services Spectrum Licenses                              
Business Acquisition [Line Items]                              
Acquisitions             $ 100                
Data Center Sale with Equinix                              
Business Acquisition [Line Items]                              
Proceeds from dispositions of businesses         $ 3,600                    
Operating Revenues                   100 100 200      
Operating income                   $ 100 100 $ 100      
Derecognition of net assets                             $ 1,400
Selling, general and administrative expense                              
Business Acquisition [Line Items]                              
Pre-tax gain on sale of business                 $ 1,800   $ 1,800        
XO Holdings                              
Business Acquisition [Line Items]                              
Business acquisition, purchase price in cash                         $ 100 $ 1,800  
Business acquisition, cost of subsidiary acquired               $ 200              
Goodwill       $ 400                      
Intangible assets subject to amortization       $ 200                      
Yahoo! Inc.                              
Business Acquisition [Line Items]                              
Aggregate purchase price $ 4,761   $ 4,480     $ 4,830                  
Business acquisition, purchase price in cash 4,723                            
Intangible assets subject to amortization 2,586                            
Purchase price reduction due to Purchase Agreement Amendment     $ (350)                        
Post-closing liabilities arising from data breach percent retained     50.00%                        
Post-closing liabilities arising from shareholders percent retained     100.00%                        
Cash acquired 200                            
Yahoo! Inc. | Restricted Stock Units                              
Business Acquisition [Line Items]                              
Outstanding restricted stock units to be awarded to employees who transferred from yahoo $ 1,000                            
Straight Path Communications Inc.                              
Business Acquisition [Line Items]                              
Purchase price per share | $ / shares   $ 184.00                          
Aggregate purchase price   $ 3,100                          
United States and Latin America | Data Center Sale with Equinix                              
Business Acquisition [Line Items]                              
Number of data center sites that were sold | Site         23                    
Europe, Asia-Pacific and Canada | Data Center Sale with Equinix                              
Business Acquisition [Line Items]                              
Number of data center sites | Site         27