Income Taxes (Details) $ in Millions	Apr. 30, 2016 USD ($)
Operating Loss Carryforwards
Operating loss carryforwards	$ 85.0
Tax credit carryforward	1.3
State
Operating Loss Carryforwards
Net tax benefit available	2.1
Federal
Operating Loss Carryforwards
Net tax benefit available	29.8
Portion of net operating loss related to equity-based compensation	$ 5.3