Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Current assets:
Allowance for doubtful accounts	$ 607	$ 1,062
Stockholders’ equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000.0	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	117,981,000	115,333,000
Common stock, shares outstanding	117,981,000	115,333,000