Goodwill And Intangible Assets (Intangible Assets Acquired) (Details) $ in Thousands	12 Months Ended
	Apr. 30, 2019 USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 38,951
Weighted-Average Life (in years)	4 years
Reacquired franchise rights
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 10,734
Weighted-Average Life (in years)	5 years
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 18,851
Weighted-Average Life (in years)	5 years
Internally-developed software
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 8,854
Weighted-Average Life (in years)	3 years
Noncompete agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 512
Weighted-Average Life (in years)	5 years