Note B - Summary of Significant Accounting Policies - Sales (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Sales	$ 121,263	$ 121,791	$ 384,117	$ 367,056
Sales Used Autos [Member]
Sales	103,249	105,435	331,376	316,269
Wholesales Third Party [Member]
Sales	5,764	5,097	16,710	16,939
Service Contract Sales [Member]
Sales	7,094	6,784	21,072	20,327
Payment Protection Plan Revenue [Member]
Sales	$ 5,156	$ 4,475	$ 14,959	$ 13,521