v3.3.1.900
Income Taxes (Components of Net Deferred Tax Liability) (Details) - USD ($)
$ in Millions
Dec. 31, 2015
Dec. 31, 2014
Net operating loss carryforwards $ 551 $ 448
Nondeductible accruals and other 3,589 3,383
Less: Valuation allowance 342 375
Deferred Tax Assets, Net 4,014 3,572
DeferredIncomeTaxLiabilities 37,580 36,336
Total deferred tax liabilities 33,566 32,764
Differences Between Book and Tax Basis of Property and Equipment and Intangible Assets [Member]    
Deferred tax liabilities, other 36,392 35,112
Differences Between Book and Tax Basis of Investments [Member]    
Deferred tax asset, other 101 0
Deferred tax liabilities, other 0 186
Differences Between Book and Tax Basis of Indexed Debt Securities [Member]    
Deferred tax liabilities, other 457 534
Differences Between Book and Tax Basis of Foreign Subsidiaries [Member]    
Deferred tax liabilities, other 731 504
Differences Between Book and Tax Basis of Long-Term Debt [Member]    
Deferred tax asset, other $ 115 $ 116