Goodwill and Intangible Assets (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2011 States Year	Sep. 30, 2010	Sep. 30, 2009
Component of Company's Intangible Assets (Textual) [Abstract]
Amortization, customer relationships and noncompete agreement intangibles over their estimated periods of benefit, maximum period	15
Amortization expense of intangible assets	$ 20.4	$ 19.9	$ 18.4
Expected aggregate amortization expense of intangible assets for the next five fiscal years:
Fiscal 2012	20.1
Fiscal 2013	19.5
Fiscal 2014	18.6
Fiscal 2015	16.6
Fiscal 2016	$ 10.3

Component of Company's intangible assets.

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Aggregate amount of intangible asset amortization recognized as expense during the period.

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The maximum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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