Income Taxes (Details 2)	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
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	1.30%	(6.00%)	(6.40%)
State income taxes, net of federal benefit	3.80%	2.20%	3.50%
Valuation allowance adjustments	(1.60%)	0.00%	(0.20%)
Effects of foreign operations	(3.60%)	(0.60%)	(0.60%)
Other, net	(0.10%)	(0.80%)	0.70%
Effective tax rate	34.80%	29.80%	32.00%

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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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-Number 109

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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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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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by foreign tax credits generated or utilized under enacted tax laws during the period.

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