Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Sep. 30, 2018
Consolidated Balance Sheets [Abstract]
Trade, allowance	$ 1,015	$ 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	21,381,847	21,205,536
Treasury stock, shares	667,682	843,993