Acquisitions And Divestitures Acquisition of Antaya Technologies Corp. (Details) - USD ($) $ in Millions	Oct. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 1,508	$ 1,539	$ 656
Antaya Technologies Corp.
Business Acquisition [Line Items]
Business Acquisition, Percentage of Equity Interests Acquired	100.00%
Total purchase price	$ 151
Purchase price, cash consideration, net of cash acquired	140
Contingent consideration liability	11
Contingent Consideration Arrangement, Range of Outcomes, Value, High	40
Contingent Consideration Arrangement, Range of Outcomes, Value, Low	$ 0
Contingent Consideration Period	3 years
Definite-lived intangible assets	$ 75
Other assets purchased and liabilities assumed, net	(17)
Identifiable net assets acquired	58
Goodwill	93
Total purchase price allocation	$ 151
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	14 years