Warranty (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 31, 2015	Oct. 31, 2014
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Beginning balance	$ 8.6	$ 9.0
Accruals for warranties issued during the reporting period	1.3	0.9
Accruals related to pre-existing warranties (including changes in estimates)	2.2	(0.5)
Less settlements made during the period	(0.5)	(1.3)
Ending balance	$ 11.6	$ 8.1

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

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=6398077&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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

+ Details

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- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and 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 and extended product warranties (including adjustments for changes in estimates).

+ References

+ Details

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- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ References

+ Details

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