Segment Information - Schedule of Reconciliation of Reportable Segment Profit to Consolidated Total (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Restructuring costs	$ 2	$ 4	$ 2	$ 7
Separation and integration-related costs	21	6	65	17
Interest expense	37	5	47	7
Income before taxes	36	66	77	118
Operating segments
Segment Reporting Information [Line Items]
Total profit for reportable segments	92	80	164	149
Corporate
Segment Reporting Information [Line Items]
Stock-based compensation	1	(1)	3	0
Restructuring costs	0	4	0	7
Separation and integration-related costs	21	6	65	17
Interest expense	37	5	47	7
Other income, net	(3)	0	(28)	0
Income before taxes	$ 36	$ 66	$ 77	$ 118