Intangible Assets - Schedule of Intangible Assets by Class (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,787	$ 3,695
Accumulated Amortization	1,980	1,862
Net Book Value	1,807	1,833
Customer related intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,213	2,200
Accumulated Amortization	1,105	1,043
Net Book Value	1,108	1,157
Acquired software and technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	525	507
Accumulated Amortization	445	432
Net Book Value	80	75
Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	117	117
Accumulated Amortization	61	57
Net Book Value	56	60
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	702	641
Accumulated Amortization	265	233
Net Book Value	437	408
Purchased software
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	230	230
Accumulated Amortization	104	97
Net Book Value	$ 126	$ 133