Equity-Based Compensation - Restricted Stock Units (Details) - Restricted stock units $ / shares in Units, shares in Thousands, $ in Millions	9 Months Ended
	Jan. 31, 2020 USD ($) $ / shares shares
Number of Restricted Stock Units
Outstanding, beginning of the period (in shares) | shares	193
Granted (in shares) | shares	233
Vested (in shares) | shares	(94)
Forfeited (in shares) | shares	(39)
Outstanding, end of the period (in shares) | shares	293
Weighted Average Exercise Price
Outstanding, beginning of period (in dollars per share) | $ / shares	$ 25.48
Granted (in dollars per share) | $ / shares	21.67
Vested (in dollars per share) | $ / shares	24.89
Forfeited (in dollars per share) | $ / shares	25.29
Outstanding, end of the period (in dollars per share) | $ / shares	$ 22.62
Unrecognized compensation cost | $	$ 4.6
Weighted-average period for recognition of unrecognized compensation expense (in years)	2 years