Income Taxes (Details 2)	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
A reconciliation from the U.S. federal statutory tax rate to our effective tax rate
U.S. federal statutory tax rate	35.00%	35.00%	35.00%
Difference in tax rate due to
Noncontrolling interests not subject to tax	(6.00%)	(6.40%)	(8.00%)
State income taxes, net of federal benefit	2.20%	3.50%	2.50%
Effects of international operations	(0.60%)	(0.60%)	(0.30%)
Other, net	(0.80%)	0.50%	0.20%
Effective tax rate	29.80%	32.00%	29.40%

Difference in tax rate due to.

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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.

+ References

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-Publisher FASB

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

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.

+ References

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

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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 difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

+ References

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

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

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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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