Income Taxes Rate Reconciliation (Details) (USD $) In Thousands	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation Abstract
Tax at statutory rate of 35%	$ 109,401	$ 112,922	$ 98,231
Common stock dividends deductible for tax reporting	1,930	1,785	1,591
State taxes (net of federal benefit)	8,184	11,445	(13)
Settlement of uncertain tax positions	(4,950)	0	0
Penalties	2,294	107	72
Other, net	690	1,673	663
Income tax expense (benefit)	$ 113,689	$ 124,362	$ 97,362

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

-Section 08

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The portion of the difference between total income tax expense (benefit) as reported in the Income Statement for the period and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles, not otherwise listed in the existing taxonomy.

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The portion of the difference, between total income tax expense (benefit) as reported in the Income Statement for the year/accounting period and the expected income tax expense (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 (benefit) as reported in the Income Statement for the period and the expected income tax expense (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 (benefit).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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The portion of the difference between total income tax expense (benefit) as reported in the Income Statement and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to domestic income tax settlements for the period.

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