Revenue from Contracts with Customers - Disaggregation of Revenue (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Products
Disaggregation of Revenue [Line Items]
Net sales	$ 801
Products | Direct
Disaggregation of Revenue [Line Items]
Net sales	466
Products | Indirect
Disaggregation of Revenue [Line Items]
Net sales	335
Products | Systems and Integration
Disaggregation of Revenue [Line Items]
Net sales	182
Products | Devices
Disaggregation of Revenue [Line Items]
Net sales	619
Products | Managed & Support Services
Disaggregation of Revenue [Line Items]
Net sales	0
Products | Americas
Disaggregation of Revenue [Line Items]
Net sales	599
Products | EMEA
Disaggregation of Revenue [Line Items]
Net sales	118
Products | AP
Disaggregation of Revenue [Line Items]
Net sales	84
Services
Disaggregation of Revenue [Line Items]
Net sales	667
Services | Direct
Disaggregation of Revenue [Line Items]
Net sales	657
Services | Indirect
Disaggregation of Revenue [Line Items]
Net sales	10
Services | Systems and Integration
Disaggregation of Revenue [Line Items]
Net sales	168
Services | Devices
Disaggregation of Revenue [Line Items]
Net sales	0
Services | Managed & Support Services
Disaggregation of Revenue [Line Items]
Net sales	499
Services | Americas
Disaggregation of Revenue [Line Items]
Net sales	396
Services | EMEA
Disaggregation of Revenue [Line Items]
Net sales	220
Services | AP
Disaggregation of Revenue [Line Items]
Net sales	$ 51