Shareholders' Equity (Details) $ / shares in Units, $ in Thousands	12 Months Ended			104 Months Ended
	Jun. 30, 2019 USD ($) votes $ / shares shares	Jun. 30, 2018 USD ($) $ / shares shares	Jun. 30, 2017 shares	Jun. 30, 2019 USD ($) $ / shares shares	Nov. 08, 2017 shares	Nov. 07, 2017 shares
Common Shares
Common shares, authorized (in shares) | shares	100,000,000	100,000,000		100,000,000	100,000,000	50,000,000
Common shares, par value (in dollars per share)	$ 0.002	$ 0.002		$ 0.002
Common stock, dividends declared per share	$ 0
Number of Votes Per Each Common Share | votes	1
Treasury Shares
Share repurchase program, authorized amount | $	$ 30,000			$ 30,000
Share repurchase program, remaining authorized amount | $	$ 13,400			$ 13,400
Treasury stock acquired, shares repurchased (in shares) | shares	111,509	950,046	0	6,784,648
Treasury stock acquired less handling fees | $	$ 1,500	$ 15,100
Treasury stock acquired | $	$ 1,501	$ 15,098		$ 67,300
Treasury stock acquired, average price per share (in dollars per share)	$ 13.43	$ 15.86		$ 9.92
Treasury stock retired (in shares) | shares	0
Treasury stock reissued average price per share				5.55
Treasury Stock Reissued [Member]
Treasury Shares
Treasury stock acquired, average price per share (in dollars per share)				$ 10.41
Treasury stock reissued (in shares) | shares				138,828