v3.4.0.3
Changes in Balances of Accumulated Other Comprehensive Income by Component (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Equity And Accumulated Other Comprehensive Income [Line Items]    
Balance at January 1, 2016 $ 550  
Other comprehensive income (loss) 103  
Amounts reclassified to net income (194)  
Other comprehensive loss attributable to Verizon (91) $ (195)
Balance at March 31, 2016 459  
Foreign currency translation adjustments    
Equity And Accumulated Other Comprehensive Income [Line Items]    
Balance at January 1, 2016 (554)  
Other comprehensive income (loss) 30  
Other comprehensive loss attributable to Verizon 30  
Balance at March 31, 2016 (524)  
Unrealized loss on cash flow hedges    
Equity And Accumulated Other Comprehensive Income [Line Items]    
Balance at January 1, 2016 (278)  
Other comprehensive income (loss) 75  
Amounts reclassified to net income (133)  
Other comprehensive loss attributable to Verizon (58)  
Balance at March 31, 2016 (336)  
Unrealized loss on marketable securities    
Equity And Accumulated Other Comprehensive Income [Line Items]    
Balance at January 1, 2016 101  
Other comprehensive income (loss) (2)  
Amounts reclassified to net income (16)  
Other comprehensive loss attributable to Verizon (18)  
Balance at March 31, 2016 83  
Defined benefit pension and postretirement plans    
Equity And Accumulated Other Comprehensive Income [Line Items]    
Balance at January 1, 2016 1,281  
Amounts reclassified to net income (45)  
Other comprehensive loss attributable to Verizon (45)  
Balance at March 31, 2016 $ 1,236