Stock Incentive Plans - Narrative (Details) $ in Millions	3 Months Ended
Jun. 30, 2020 USD ($) anniversary shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan term	10 years
Total unrecognized compensation expense related to unvested awards, net of expected forfeitures \| $	$ 0
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares to be received (in shares) \| shares	1
Total unrecognized compensation expense related to unvested awards, net of expected forfeitures \| $	$ 194
Weighted average period over which cost is expected to be recognized (in years)	2 years 3 months 29 days
Restricted Stock Units \| Five Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual installments	5 years
Restricted Stock Units \| Ten Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual installments	10 years
Restricted Stock Units \| Fifteen Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual installments	15 years
Restricted Stock Units \| Service-based RSU's
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of anniversaries over which shares are settled \| anniversary	10
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance period	3 years
Award vesting rights, percentage	25.00%
DXC Share Purchase Plan \| Stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased under plan (in shares) \| shares	14,882

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