Recent Accounting Pronouncements (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2017
Income Tax Provision
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefits from share-based compensation awards	$ 6	$ 31

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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