Preferred and Common Stockholder's Equity - Summary of Common Shares Issued and Outstanding (Detail) - shares shares in Millions	9 Months Ended	12 Months Ended
	Mar. 31, 2020	Jun. 30, 2019
Equity [Abstract]
Beginning common stock issued, Beginning balance	73.5	70.6
Beginning common stock outstanding, Beginning balance	73.5	70.6
Common stock issued upon exercise of options and employee stock plans	1.0	4.5
Repurchase and retirement of common stock		(1.6)
Common stock issued, Ending balance	74.5	73.5
Common stock outstanding, Ending balance	74.5	73.5