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

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