CONDENSED CONSOLIDATED COMBINED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 29	$ 24	$ 60	$ 53
Other comprehensive income (loss), net of tax:
Cash flow hedge adjustments, net of tax	(3)	6	(21)	5
Comprehensive income	$ 26	$ 30	$ 39	$ 58