Note B - Summary of Significant Accounting Policies - Sales (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Sales	$ 652,992	$ 586,508	$ 537,528
Sales Used Autos [Member]
Sales	567,816	506,184	462,956
Wholesales Third Party [Member]
Sales	28,966	27,376	25,638
Service Contract Sales [Member]
Sales	31,480	30,243	28,482
Payment Protection Plan Revenue [Member]
Sales	$ 24,730	$ 22,705	$ 20,452