Derivatives - Derivative Instruments Designated as Cash Flow Hedges in OCI (Details) - Cash Flow Hedging - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Oct. 31, 2015	Nov. 01, 2014	Oct. 31, 2015	Nov. 01, 2014
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) recorded in AOCI, beginning of period			$ 6.6
Gains (losses) recorded in AOCI, end of period	$ (5.5)	$ (8.1)	(5.5)	$ (8.1)
Foreign currency contracts
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) recorded in AOCI, beginning of period	0.4	(3.2)	0.9	(2.3)
Current period gains (losses) recognized in OCI	0.2	1.6	(0.4)	0.4
Gains (losses) recorded in AOCI, end of period	0.5	(1.3)	0.5	(1.3)
Commodity contracts
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) recorded in AOCI, beginning of period	(8.3)	(4.9)	5.7	(18.8)
Current period gains (losses) recognized in OCI	4.0	(4.3)	(10.6)	(2.6)
Gains (losses) recorded in AOCI, end of period	(3.9)	(6.8)	(3.9)	(6.8)
Interest Rate Contract
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) recorded in AOCI, beginning of period	(0.9)	0.0	0.0	0.0
Current period gains (losses) recognized in OCI	(2.0)	0.0	(4.0)	0.0
Gains (losses) recorded in AOCI, end of period	(2.1)	0.0	(2.1)	0.0
Interest rate swaps
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) recorded in AOCI, beginning of period			0.0
Gains (losses) recorded in AOCI, end of period	(2.1)	0.0	(2.1)	0.0
Cost of Sales \| Foreign currency contracts
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) reclassified from AOCI to net income	(0.1)	0.3	0.0	0.6
Cost of Sales \| Commodity contracts
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) reclassified from AOCI to net income	0.4	2.4	1.0	14.6
Interest expense, net \| Interest Rate Contract
Movement in Accumulated Other Comprehensive Income [Roll Forward]
Gains (losses) reclassified from AOCI to net income	$ 0.8	$ 0.0	$ 1.9	$ 0.0

Movement in Accumulated Other Comprehensive Income [Roll Forward]

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- Definition

Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, including portion attributable to noncontrolling interest. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

+ References

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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