Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 643	$ 718
Prepaid expenses and other current assets, fair value (in dollars)	$ 1,200	$ 2,200
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	31,485,857	30,742,662
Common stock, shares outstanding	31,485,857	30,742,662