Earnings (Loss) Per Share - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of earnings per share			1.8
Remaining authorized stock repurchase amount	$ 33.2		$ 33.2
Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of earnings per share	0.1	0.2		0.1