Allowance For Credit Losses On US Customer In-House Finance Receivables (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended		12 Months Ended
	Jul. 28, 2012	Jul. 30, 2011	Jan. 28, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance	$ (78.6)	$ (67.8)	$ (78.1)
Ending receivable balance evaluated for impairment	1,102.8	969.0	1,155.5
Accounts receivable, net	1,032.2	906.8	1,088.2
US Customer In-House Finance Receivables
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	(78.1)	(67.8)	(67.8)
Charge-offs	49.5	40.3	92.8
Recoveries	11.1	9.9	19.3
Provision	(61.1)	(50.2)	(122.4)
Ending balance	(78.6)	(67.8)	(78.1)
Ending receivable balance evaluated for impairment	1,102.8	969.0	1,155.5
Accounts receivable, net	$ 1,024.2	$ 901.2	$ 1,077.4