Acquisitions - Identified Intangible Assets Acquired (Details) - HPES $ in Millions	Apr. 01, 2017 USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 6,194
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 5,200
Customer relationships | Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (Years)	10 years
Customer relationships | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (Years)	13 years
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 141
Estimated Useful Lives (Years)	10 years
Third-party purchased software
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 499
Third-party purchased software | Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (Years)	2 years
Third-party purchased software | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful Lives (Years)	7 years
Deferred contract costs
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 354