Earnings Per Share - Schedule of Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	1 Months Ended	2 Months Ended	3 Months Ended			6 Months Ended
	Jun. 30, 2018	May 31, 2018	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net income	$ (20)	$ 49	$ 29	$ 31	$ 24	$ 60	$ 53
Common share information:
Weighted average common shares outstanding for basic EPS (in shares)			162,220		165,490	162,510	165,540
Dilutive effect of stock options and equity awards (in shares)			680		300	580	280
Weighted average common shares outstanding for diluted EPS (in shares)			162,900		165,790	163,090	165,820
Earnings per common share:
Basic (in dollars per share)			$ 0.18		$ 0.15	$ 0.37	$ 0.32
Diluted (in dollars per share)			$ 0.18		$ 0.14	$ 0.37	$ 0.32