Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
	Jun. 28, 2019	Jul. 31, 2019	Jul. 31, 2019	Jul. 31, 2018
Business Acquisition [Line Items]
Expense period	2 years
Cash performance incentives and share based compensation, vesting period	3 years
Revenues recognized		$ 3,600
Pretax losses recognized		5,300
Pro forma revenues			$ 156,900	$ 152,000
Pro forma pretax losses			218,100	$ 211,200
ROU asset		486,147	486,147
Lease liability		$ 479,173	$ 479,173
Wave
Business Acquisition [Line Items]
Acquisition	$ 407,000
Amounts held in escrow	11,400
Compensation payable	$ 8,200