v2.4.1.9
Changes in Balances of Accumulated Other Comprehensive Income by Component (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Equity And Accumulated Other Comprehensive Income [Line Items]      
Balance at January 1, 2014 $ 2,358us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax    
Other comprehensive income (loss) (363)us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax    
Amounts reclassified to net income (884)us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax    
Net other comprehensive income (loss)attributable to Verizon (1,247)us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent 123us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent 966us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
Balance at December 31, 2014 1,111us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax 2,358us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax  
Foreign currency translation adjustments      
Equity And Accumulated Other Comprehensive Income [Line Items]      
Balance at January 1, 2014 853us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedTranslationAdjustmentMember
   
Other comprehensive income (loss) (288)us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedTranslationAdjustmentMember
   
Amounts reclassified to net income (911)us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedTranslationAdjustmentMember
   
Net other comprehensive income (loss)attributable to Verizon (1,199)us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedTranslationAdjustmentMember
   
Balance at December 31, 2014 (346)us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedTranslationAdjustmentMember
   
Unrealized gain on cash flow hedges      
Equity And Accumulated Other Comprehensive Income [Line Items]      
Balance at January 1, 2014 113us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
   
Other comprehensive income (loss) (89)us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
   
Amounts reclassified to net income (108)us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
   
Net other comprehensive income (loss)attributable to Verizon (197)us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
   
Balance at December 31, 2014 (84)us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
   
Unrealized gain on marketable securities      
Equity And Accumulated Other Comprehensive Income [Line Items]      
Balance at January 1, 2014 117us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
   
Other comprehensive income (loss) 14us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
   
Amounts reclassified to net income (19)us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
   
Net other comprehensive income (loss)attributable to Verizon (5)us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
   
Balance at December 31, 2014 112us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
   
Defined benefit pension and postretirement plans      
Equity And Accumulated Other Comprehensive Income [Line Items]      
Balance at January 1, 2014 1,275us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
   
Amounts reclassified to net income 154us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
   
Net other comprehensive income (loss)attributable to Verizon 154us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
   
Balance at December 31, 2014 $ 1,429us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember