Business Acquisitions, Goodwill and Intangible Assets (Details 3) (USD $)	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2014
Estimated amortization expense of intangible assets for the remainder of fiscal 2013 and for the succeeding years
2015 (nine months remaining)	$ 152,600,000
2016	152,900,000
2017	83,600,000
2018	80,400,000
2019	79,500,000
Thereafter	309,900,000
Intangible Assets, Net	858,860,000us-gaap_FiniteLivedIntangibleAssetsNet		90,238,000us-gaap_FiniteLivedIntangibleAssetsNet
Gross Amount	1,101,500,000		280,900,000
Accumulated Amortization	(242,600,000)		(190,700,000)
Intangible Assets, Net	858,860,000us-gaap_FiniteLivedIntangibleAssetsNet		90,238,000us-gaap_FiniteLivedIntangibleAssetsNet
Amortization expense	51,900,000us-gaap_AmortizationOfIntangibleAssets	5,100,000us-gaap_AmortizationOfIntangibleAssets
Backlog and customer relationship
Estimated amortization expense of intangible assets for the remainder of fiscal 2013 and for the succeeding years
Intangible Assets, Net	857,700,000		88,800,000
Gross Amount	1,084,500,000		271,600,000
Accumulated Amortization	(226,800,000)		(182,800,000)
Intangible Assets, Net	857,700,000		88,800,000
Backlog and customer relationship \| Minimum
Estimated amortization expense of intangible assets for the remainder of fiscal 2013 and for the succeeding years
Amortization Period	1 year
Backlog and customer relationship \| Maximum
Estimated amortization expense of intangible assets for the remainder of fiscal 2013 and for the succeeding years
Amortization Period	11 years
Trademark / tradename
Estimated amortization expense of intangible assets for the remainder of fiscal 2013 and for the succeeding years
Intangible Assets, Net	1,200,000		1,400,000
Gross Amount	17,000,000		9,300,000
Accumulated Amortization	(15,800,000)		(7,900,000)
Intangible Assets, Net	$ 1,200,000		$ 1,400,000
Amortization Period	2 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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