Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021
Current assets:
Restricted cash	$ 907	$ 1,907
Allowance, accounts receivable	$ 3,309	$ 3,664
Stockholders' equity:
Preferred stock, par value	$ 0.003	$ 0.003
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.001455	$ 0.001455
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	72,960,000	72,960,000
Treasury stock, shares	9,877,000	9,702,000
Treasury stock held for deferred compensation, shares	167,000	167,000