Income Taxes (Differences Between Effective Rates And Statutory Federal Income Tax Rate Computed On Income Before Income Tax Expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Income Taxes [Abstract]
Federal income tax expense computed at statutory Federal rate, Amount	$ 20,073	$ 36,878	$ 36,828
Federal income tax expense computed at statutory Federal rate, Percentage	35.00%	35.00%	35.00%
Increases (Decreases) In Taxes Resulting From:
State taxes, net of Federal tax effect, Amount	1,993	3,064	3,051
State taxes, net of Federal tax effect, Percentage	3.40%	2.90%	2.90%
Net tax-exempt interest income, Amount	(577)	(624)	(579)
Net tax-exempt interest income, Percentage	(1.00%)	(0.60%)	(0.60%)
Change in cash surrender value of BOLI, Amount	(638)	(421)	(406)
Change in cash surrender value of BOLI, Percentage	(1.10%)	(0.40%)	(0.40%)
Low income housing tax credits, Amount	(1,397)	(1,209)	(1,013)
Low income housing tax credits, Percentage	(2.40%)	(1.10%)	(1.00%)
Other, Amount	(505)	(163)	1,045
Other, Percentage	(0.90%)	(0.20%)	1.10%
Income tax expense	$ 18,949	$ 37,525	$ 38,926
Income tax expense, Percentage	33.00%	35.60%	37.00%

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Increases (Decreases) in taxes resulting from:

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Low Income Housing Tax Credits

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to income that is exempt from income taxes under enacted tax laws.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to income that is exempt from income taxes under enacted tax laws.

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