Stock Option Plans Other Stock Option Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost for stock options	$ 848	$ 1,087	$ 1,213
Weighted average grant date fair value	$ 3.53	$ 3.89	$ 4.43
Total intrinsic value of options exercised	125	259	975
Grant date fair value of options exercised	54	312	482
Cash received from options exercises	0	1,630	1,760
Tax benefit realized for option exercises	$ 0	$ 37	$ 227

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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