Warranty reserve - Warranty reserve (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Aug. 01, 2015	Aug. 02, 2014	Aug. 01, 2015	Aug. 02, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of period	$ 44.6	$ 19.4	$ 44.9	$ 19.1
Standard Product Warranty Accrual, Additions from Business Acquisition	0.0	28.8	0.0	28.8
Product Warranty Expense	1.9	2.3	4.9	4.0
Product Warranty Accrual, Payments	(3.4)	(2.4)	(6.7)	(3.8)
Balance at end of period	$ 43.1	$ 48.1	$ 43.1	$ 48.1

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=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

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

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services 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)(3,4))

-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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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- Definition

Liability for a standard product warranty acquired in a business acquisition. Does not include any liability for an extended warranty acquired in a business acquisition.

+ References

+ Details

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