Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015	Mar. 31, 2015
Accounts receivable, allowances	$ 9,396	$ 6,298	$ 8,929
Common stock (voting), par value	$ 0.01	$ 0.01	$ 0.01
Common stock (voting), shares authorized	100,000,000	100,000,000	100,000,000
Common stock (voting), issued	59,521,648	49,790,743	49,607,351
Common Stock (voting), outstanding	59,521,648	49,790,743	49,607,351
Undesignated Preferred Stock, shares authorized	5,000,000	5,000,000	5,000,000
Undesignated Preferred Stock, issued	0	0	0
Undesignated Preferred Stock, outstanding	0	0	0