Earnings (Loss) Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Net (loss) income attributable to DXC common shareholders:
From continuing operations	$ (5,369)	$ 1,222	$ 1,515
From discontinued operations	0	35	236
Net (loss) income attributable to DXC common stockholders	$ (5,369)	$ 1,257	$ 1,751
Common share information:
Weighted average common shares outstanding for basic EPS (in shares)	258,570	277,540	284,930
Dilutive effect of stock options and equity awards (in shares)	0	3,890	4,840
Weighted average common shares outstanding for diluted EPS (in shares)	258,570	281,430	289,770
Basic EPS:
Continuing operations (in dollars per share)	$ (20.76)	$ 4.40	$ 5.32
Discontinued operations (in dollars per share)	0	0.13	0.83
Basic EPS (in dollars per share)	(20.76)	4.53	6.15
Diluted EPS:
Continuing operations (in dollars per share)	(20.76)	4.35	5.23
Discontinued operations (in dollars per share)	0	0.12	0.81
Diluted EPS (in dollars per share)	$ (20.76)	$ 4.47	$ 6.04