v2.4.1.9
Income Statement Information (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]      
Depreciation expense $ 14,966us-gaap_Depreciation $ 15,019us-gaap_Depreciation $ 14,920us-gaap_Depreciation
Interest costs on debt balances 5,291us-gaap_InterestCostsIncurred 3,421us-gaap_InterestCostsIncurred 2,977us-gaap_InterestCostsIncurred
Capitalized interest costs (376)us-gaap_InterestCostsCapitalized (754)us-gaap_InterestCostsCapitalized (406)us-gaap_InterestCostsCapitalized
Advertising expense $ 2,526us-gaap_AdvertisingExpense $ 2,438us-gaap_AdvertisingExpense $ 2,381us-gaap_AdvertisingExpense