Stock Options Other Stock Option Information (Details) (USD $)	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost for stock options	$ 1,087,000	$ 1,213,000	$ 1,327,000
Weighted average grant date fair value	$ 4	$ 4	$ 2
Total intrinsic value of options exercised	259,000	975,000	65,000
Grant date fair value of options exercised	312,000	482,000	57,000
Cash received from options exercises	1,630,000	1,760,000	158,000
Tax benefit realized for option exercises	$ 37,000	$ 227,000	$ 21,000

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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Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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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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