CONDENSED STATEMENTS OF SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Common shares [Member]	Accumulated other comprehensive income (loss) [Member]	Retained earnings/(accumulated deficit) [Member]	Total
Balance at beginning at Jun. 30, 2018	$ 19,835	$ (153)	$ (2,406)	$ 17,276
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	18
Share repurchases	(2,560)
Shares withheld from common stock issued to employees to pay employee payroll taxes	(101)
Exercise of stock options	7
Exercise of stock options (in shares)				3,000
ESPP shares issued	10
Cumulative effect of change in accounting principle
Net income			2,528	$ 2,528
Net change in unrealized gain (loss) from marketable securities, net of taxes		(196)
Balance at end at Dec. 31, 2018	17,209	(349)	122	16,982
Balance at beginning at Sep. 30, 2018	18,639	145	(1,057)	17,727
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	8
Share repurchases	(1,445)
Shares withheld from common stock issued to employees to pay employee payroll taxes
Exercise of stock options	7
ESPP shares issued
Cumulative effect of change in accounting principle
Net income			1,179	1,179
Net change in unrealized gain (loss) from marketable securities, net of taxes		(494)
Balance at end at Dec. 31, 2018	17,209	(349)	122	16,982
Balance at beginning at Jun. 30, 2019	15,815	(549)	1,742	$ 17,008
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	19
Share repurchases	(2,215)
Shares withheld from common stock issued to employees to pay employee payroll taxes
Exercise of stock options
Exercise of stock options (in shares)
ESPP shares issued	15
Cumulative effect of change in accounting principle			42
Net income			2,354	$ 2,354
Net change in unrealized gain (loss) from marketable securities, net of taxes		649
Balance at end at Dec. 31, 2019	13,634	100	4,138	17,872
Balance at beginning at Sep. 30, 2019	15,161	(605)	2,889	17,444
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	8
Share repurchases	(1,535)
Shares withheld from common stock issued to employees to pay employee payroll taxes
Exercise of stock options
ESPP shares issued
Cumulative effect of change in accounting principle
Net income			1,249	1,249
Net change in unrealized gain (loss) from marketable securities, net of taxes		705
Balance at end at Dec. 31, 2019	$ 13,634	$ 100	$ 4,138	$ 17,872