CONDENSED CONSOLIDATED COMBINED STATEMENTS OF OPERATIONS (unaudited) - USD ($) shares in Thousands, $ in Millions		3 Months Ended		9 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue		$ 1,075	$ 722	$ 2,936	$ 2,104
Costs of services (excludes depreciation and amortization and restructuring costs)		816	550	2,226	1,632
Selling, general, and administrative (excludes depreciation and amortization and restructuring costs)		76	51	226	132
Depreciation and amortization		76	46	214	116
Restructuring costs		1	3	3	10
Separation and integration-related costs		19	27	84	44
Interest expense, net		37	0	84	7
Other expense (income), net		2	0	(26)	0
Total costs and expenses		1,027	677	2,811	1,941
Income before taxes		48	45	125	163
Income tax expense (benefit)		10	(59)	34	(13)
Net income		$ 38	$ 104	$ 91	$ 176
Earnings per common share
Basic (in dollars per share)	[1]	$ 0.23	$ 0.73	$ 0.55	$ 1.24
Diluted (in dollars per share)	[1]	$ 0.23	$ 0.73	$ 0.55	$ 1.24
Number of shares from distribution in a spinoff (in shares)		164,320	142,430	165,020	142,430

[1] Earnings per share information for the three and nine months ended December 31, 2017 is computed using the 142.43 million shares of Perspecta common stock resulting from the Distribution, as Perspecta did not operate as a stand-alone entity during the period and therefore, no Perspecta common stock, stock options or other equity awards were outstanding and no dividends were declared or paid by Perspecta.