CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Sep. 30, 2014
Current assets
Allowance for doubtful accounts	$ 1,242	$ 1,392
Stockholders' equity
Common stock: Authorized (in shares)	200,000,000	200,000,000
Common stock: par value (in dollars per share)	$ 0.001	$ 0.001
Common stock: Issued (in shares)	33,452,575	31,927,601
Treasury stock at cost, shares (in shares)	9,041,657	8,142,687