Acquisitions And Divestitures Acquisition of Ottomatika, Inc. (Details) - USD ($) $ in Millions	Jul. 23, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill		$ 1,944	$ 1,502	$ 1,531
Ottomatika, Inc.
Business Acquisition [Line Items]
Business Acquisition, Percentage of Equity Interests Acquired	100.00%
Consideration transferred	$ 32
Purchase price, cash consideration, net of cash acquired	16
Purchase price, deferred consideration	$ 11
Deferred Consideration Period	3 years
Contingent Consideration Arrangement, Range of Outcomes, Value, Low	$ 0
Contingent Consideration Arrangement, Range of Outcomes, Value, High	$ 5
Contingent Consideration Period	3 years
Contingent consideration liability	$ 5
Fair value of previously held investment	4
Total purchase price	36
Indefinite-lived intangible assets	24
Definite-lived intangible assets	1
Other assets purchased and liabilities assumed, net	(8)
Identifiable net assets acquired	17
Goodwill	19
Total purchase price allocation	$ 36
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years
Ottomatika, Inc. | Other income (expense), net
Business Acquisition [Line Items]
Gain on previously held investment	$ 2