Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Apr. 30, 2015	Apr. 30, 2014
Commitments And Contingencies [Line Items]
Standard guarantee accrual amount	$ 7,600	$ 10,600	$ 8,400
Contingent business acquisition obligations	10,650		10,667
Lines of credit, total obligation	77,400
Remaining franchise equity lines of credit-undrawn commitment	38,800
Financing Receivables, Line of Credit Facility, Compensating Balances	225,000
Amounts deferred for new extended service plans issued	920	873
Deferred Revenue, Revenue Recognized	27,703	24,253
Deferred Revenue	131,386	121,857	$ 158,169	$ 145,237
Level 3
Commitments And Contingencies [Line Items]
Contingent business acquisition obligations		$ 9,168
Peace of Mind Franchise [Member]
Commitments And Contingencies [Line Items]
Amounts deferred for new extended service plans issued	100
Deferred Revenue, Revenue Recognized	3,400
Deferred Revenue	$ 28,300