CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Mar. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 76	$ 60
Intangible assets, accumulated amortization	4,262	3,399
Property and equipment, accumulated depreciation	$ 4,317
Property and equipment, accumulated depreciation		$ 3,958
DXC stockholders’ equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	750,000,000	750,000,000
Common stock, issued (in shares)	255,605,750	270,213,891
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock in treasury, at cost (in shares)	2,132,967	1,788,658