Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2018	Jun. 30, 2018
Statement Of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	2,500,000	2,500,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	15,000,000	15,000,000
Common stock, shares issued (in shares)	4,495,290	4,496,873
Common stock, shares outstanding (in shares)	4,095,374	4,097,346
Treasury stock, shares at cost (in shares)	399,916	399,527