CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 811	$ 746
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	30,000,000	30,000,000
Common stock, shares issued	12,199,511	12,031,243
Treasury stock, shares	806,018	670,181