Warranties (Details) - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Sep. 30, 2015
Changes in warranty liability
Balance at beginning of period	$ 92.1	$ 101.9
Warranty provisions	34.0	31.8
Settlements made	(40.1)	(38.7)
Changes in liability for pre-existing warranties, net	2.0	(2.7)
Premiums received	11.0	9.3
Amortization of premiums received	(8.2)	(6.8)
Foreign currency translation	(0.4)	(1.9)
Balance at end of period	90.4	$ 92.9
Extended Product Warranty Accrual	$ 29.7		$ 26.4
Minimum
Product Warranty Liability [Line Items]
Product warranty term	6 months
Maximum
Product Warranty Liability [Line Items]
Product warranty term	5 years

Standard Product, Warranty Term

No definition available.

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- Definition

Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard product warranty liability.

+ References

+ Details

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- Definition

Total increases or decreases in the extended product warranty liability for the period. Does not include increases or decreases in the standard warranty liability.

+ References

+ Details

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- Definition

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting extended product warranties (including adjustments related to changes in estimates). Does not include any Increase or Decrease in the liability for accruals related to standard product warranties.

+ References

+ Details

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Period Type:	duration

- 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

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(5))
-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Increase or Decrease in standard product warranty liability due to currency translation. Does not include any Increase or Decrease in an extended product warranty liability due to currency translation.

+ References

+ Details

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- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

+ References

+ Details

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- Definition

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard product warranties (including adjustments related to changes in estimates). Does not include any Increase or Decrease in the liability for accruals related to extended product warranties.

+ References

+ Details

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- Definition

Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

+ References

+ Details

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