Note B - Summary of Significant Accounting Policies - Sales (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Sales	$ 130,427	$ 133,170	$ 258,701	$ 262,854
Sales Used Autos [Member]
Sales	111,922	115,392	223,035	228,127
Wholesales Third Party [Member]
Sales	6,115	5,529	11,452	10,946
Service Contract Sales [Member]
Sales	7,212	7,217	14,116	13,978
Payment Protection Plan Revenue [Member]
Sales	$ 5,178	$ 5,032	$ 10,098	$ 9,803