Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Statement Of Financial Position [Abstract]
Trade accounts receivable, net of allowance	$ 1,395	$ 2,449	$ 2,516
Non current financing receivables, net of allowance	$ 1,020	$ 500	$ 0
Preferred stock, shares authorized	1,000,000	1,000,000	1,000,000
Preferred stock, shares issued	0	0	0
Preferred stock, shares outstanding	0	0	0
Common stock, par value	$ 0.01	$ 0.01	$ 0.01
Common stock, shares authorized	20,000,000	20,000,000	20,000,000
Common stock, shares issued	13,438,316	13,328,066	13,147,916
Common stock, shares outstanding	13,438,316	13,328,066	13,147,916