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v3.7.0.1

New Accounting Guidance - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract] |  |
Effective income tax rate reconciliation, share-based compensation, excess tax benefit, amount | $ 44 | $ 18

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