Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Accounts receivable:
Allowance for doubtful accounts	$ 227	$ 148
Shareholders' equity:
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	50,000	50,000
Common stock, shares issued (in shares)	36,461	35,803
Common stock, shares outstanding (in shares)	29,551	28,893
Treasury stock, shares held (in shares)	6,910	6,910

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