Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Consolidated Balance Sheets [Abstract]
Trade, allowance	$ 870	$ 868
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	22,049,529	22,049,529
Common stock, shares outstanding	21,286,103	21,205,536
Treasury stock, shares	763,426	843,993