Earnings Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended	9 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share Detail [Abstract]
Net income applicable to common stock	$ 2,952	$ 9,681	$ 147,612	$ 136,028
Weighted Average Number of Shares Outstanding, Basic	51,243	50,664	51,153	50,422
Weighted Average Number of Shares Outstanding, Diluted	51,314	50,918	51,235	50,638
Earnings Per Share, Basic	$ 0.06	$ 0.19	$ 2.89	$ 2.70
Stock-based compensation plans	71	254	82	216
Diluted EPS	$ 0.06	$ 0.19	$ 2.88	$ 2.69

The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 21
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 36, 37, 38

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Publisher SEC
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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Number of shares issued during the period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

+ References

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

+ References

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