Income Taxes (Details 4) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Unrecognized tax benefits, excluding interest and penalties
Gross unrecognized tax benefits balance at beginning of year	$ 43.9	$ 38.9	$ 40.8
Additions based on tax positions related to the current year	2.3	2.1	1.0
Additions based on tax positions related to prior years	14.9	11.6	2.2
Reductions based on tax positions related to prior years	0.0	(1.0)	0.0
Reductions related to settlements with taxing authorities	(27.1)	(4.3)	0.0
Reductions related to lapses of statute of limitations	(1.6)	(1.6)	(4.2)
Effect of foreign currency translation	0.0	(1.8)	(0.9)
Gross unrecognized tax benefits balance at end of year	$ 32.4	$ 43.9	$ 38.9

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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