Goodwill and Other Intangibles, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill acquired during period		$ 578
Impairment of goodwill	$ 0	0	$ 0
Goodwill	2,370	2,370
Accumulated impairment loss	243	243
Other intangible assets	284	320
Identifiable intangible assets acquired		169
Finite-Lived Intangible Assets [Line Items]
Gross Amount	604	604
Accumulated Amortization	(320)	(284)
Finite-Lived Intangible Assets, Net	284	320
Customer relationships
Goodwill and Intangible Assets Disclosure [Abstract]
Other intangible assets	$ 244	$ 272
Finite-Lived Intangible Assets [Line Items]
Weighted Average Original Useful Life	18 years	18 years
Weighted Average Remaining Useful Life	10 years	11 years
Gross Amount	$ 553	$ 553
Accumulated Amortization	(309)	(281)
Finite-Lived Intangible Assets, Net	244	272
Technology
Goodwill and Intangible Assets Disclosure [Abstract]
Other intangible assets	$ 39	$ 46
Finite-Lived Intangible Assets [Line Items]
Weighted Average Original Useful Life	7 years	7 years
Weighted Average Remaining Useful Life	6 years	7 years
Gross Amount	$ 48	$ 48
Accumulated Amortization	(9)	(2)
Finite-Lived Intangible Assets, Net	39	46
Trade name
Goodwill and Intangible Assets Disclosure [Abstract]
Other intangible assets	$ 1	$ 2
Finite-Lived Intangible Assets [Line Items]
Weighted Average Original Useful Life	2 years	2 years
Weighted Average Remaining Useful Life	1 year	2 years
Gross Amount	$ 3	$ 3
Accumulated Amortization	(2)	(1)
Finite-Lived Intangible Assets, Net	$ 1	$ 2