Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Cash flows from operating activities:
Net earnings			$ 2,911	$ 2,628
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	$ 2,183	$ 1,913	4,428	3,711
Stock-based compensation expense	500	400	946	841
Net (gain)/loss on investments			(356)	312
Deferred income taxes			(131)	(265)
Changes in operating assets and liabilities:
Purchases of trading securities			(21,412)	(6,456)
Proceeds from maturities and sales of trading securities			16,975	9,417
Accounts receivable, net			2,180	2,162
Prepaid expenses and other assets			(1,160)	242
Accounts payable and other liabilities			389	(4,333)
Deferred revenue			(720)	(3,457)
Net cash provided by operating activities			4,050	4,802
Cash flows from investing activities:
Capitalized computer software development costs			(1,890)	(2,088)
Purchases of property and equipment, net of disposals	(128)	(180)	(238)	(894)
Net cash used in investing activities			(2,128)	(2,982)
Cash flows from financing activities:
Proceeds from exercise of stock options			6,358	3,086
Dividends paid			(6,884)	(6,767)
Net cash used in financing activities			(526)	(3,681)
Net change in cash and cash equivalents			1,396	(1,861)
Cash and cash equivalents at beginning of period			61,288	52,794
Cash and cash equivalents at end of period	62,684	50,933	62,684	50,933
Cash paid during the period for:
Income taxes, net of refunds			260	370
Supplemental disclosures of noncash operating, investing and financing activities:
Accrual of dividends payable	$ 3,505	$ 3,405	$ 3,505	$ 3,405