Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2017	Jul. 01, 2016
Segment Reporting Information [Line Items]
Revenues	$ 5,913	$ 1,930
Segment profit	679	106
Depreciation and amortization	361	166
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Segment profit	679	106
Interest income	16	10
Interest expense	(76)	(25)
Restructuring costs	(190)	(57)
Amortization of acquired intangible assets	(120)	(14)
Transaction and integration-related costs	(124)	(56)
Income (loss) before income taxes	185	(36)
GBS
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Restructuring costs	(77)	(20)
GIS
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Restructuring costs	(106)	(37)
USPS
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Restructuring costs	(7)	0
Operating segments
Segment Reporting Information [Line Items]
Revenues	5,913	1,930
Segment profit	649	161
Depreciation and amortization	336	150
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Segment profit	649	161
Operating segments \| GBS
Segment Reporting Information [Line Items]
Revenues	2,267	1,049
Segment profit	282	110
Depreciation and amortization	99	36
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Segment profit	282	110
Operating segments \| GIS
Segment Reporting Information [Line Items]
Revenues	2,969	881
Segment profit	290	51
Depreciation and amortization	222	114
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Segment profit	290	51
Operating segments \| USPS
Segment Reporting Information [Line Items]
Revenues	677	0
Segment profit	77	0
Depreciation and amortization	15	0
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Segment profit	77	0
All Other
Segment Reporting Information [Line Items]
Revenues	0	0
Segment profit	30	(55)
Depreciation and amortization	25	16
Reconciliation of Consolidated Operating Income to Income Before Taxes [Abstract]
Segment profit	$ 30	$ (55)

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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