Preferred and Common Stockholder's Equity - Summary of Common Shares Issued and Outstanding (Detail) - shares shares in Millions	6 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Equity [Abstract]
Common stock issued, Beginning balance	68.9	73.5
Common stock outstanding, Beginning balance	68.9	73.5
Common stock issued upon exercise of options and employee stock plans	4.4	1.0
Repurchase and retirement of common stock	(1.7)	(3.0)
Common stock issued, Ending balance	71.6	71.5
Common stock outstanding, Ending balance	71.6	71.5