Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Current assets:
Restricted cash	$ 3,635	$ 0
Allowance, accounts receivable	$ 3,938	$ 3,776
Stockholders' equity:
Preferred stock, par value	$ 0.003	$ 0.003
Preferred stock, shares authorized	10,000	10,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.001455	$ 0.001455
Common stock, shares authorized	150,000	150,000
Common stock, shares issued	72,960	72,960
Treasury stock, shares	11,203	11,739
Treasury stock held for deferred compensation, shares	202	186

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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