v3.7.0.1

Recent Accounting Pronouncements (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2017 | Mar. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Net cash provided by operating activities | $ 5,656 | $ 5,399
Net cash provided by (used in) financing activities | (1,141) | 643
Financial Assets and Financial Liabilities New Accounting Pronouncement [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
New Accounting Pronouncement impact on net income if adopted | 104 |
Share Based Compensation New Accounting Pronouncement [Member] | Effect of Adoption [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Decrease in income tax expense | $ 139 |
Increase in diluted earnings per share (in dollars per share) | $ 0.03 |
Net cash provided by operating activities | $ 385 | 289
Net cash provided by (used in) financing activities | $ (385) | $ (289)

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