Fair Value Fair Value Liabilities Measured on Recurring Basis Unobservable Input Reconciliation (Details) $ in Millions	6 Months Ended
Mar. 31, 2017 USD ($)
Fair Value, Liabilities [Roll Forward]
Contingent Consideration, Liability, Ending Balance	$ 10.7
Fair Value, Measurements, Recurring [Member]
Fair Value, Liabilities [Roll Forward]
Contingent Consideration, Liability, Beginning Balance	7.9
Contingent Consideration, Liability, Ending Balance	15.7
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Liabilities [Roll Forward]
Contingent Consideration, Liability, Beginning Balance	7.9
Contingent Consideration, Liability, Ending Balance	15.7
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member] \| Contingent Consideration [Member]
Fair Value, Liabilities [Roll Forward]
Contingent Consideration, Liability, Beginning Balance	7.9
Increases to Level 3 liabilities	10.7
Decreases to Level 3 liabilities	(2.9)
Contingent Consideration, Liability, Ending Balance	$ 15.7

Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

+ References

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- Details

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