Debt (Other Facilities) (Narrative) (Details) (USD $)	Jul. 31, 2013	Jan. 31, 2013
Debt Instrument [Line Items]
U.S. trade receivables	$ 2,777,486,000	$ 3,215,920,000
Line of credit, outstanding amount	40,700,000
Standby letters of credit issued	82,700,000
Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	500,000,000.0
Possible future increase of maximum borrowing capacity	750,000,000.0
Line of credit, outstanding amount	0	42,900,000
Line of credit facility, interest rate at period end		1.65%
Receivables Securitization Program
Debt Instrument [Line Items]
Maximum borrowing capacity	400,000,000.0
U.S. trade receivables	702,900,000	690,600,000
Line of credit, outstanding amount	0	83,500,000
Line of credit facility, interest rate at period end		1.02%
Other Committed And Uncommitted Revolving Credit Facilities Expiring on Various Dates Through Fiscal 2017
Debt Instrument [Line Items]
Maximum borrowing capacity	539,500,000
Line of credit, outstanding amount	40,700,000	40,600,000
Weighted average interest rate	4.40%	4.76%
Other Committed And Uncommitted Revolving Credit Facilities Expiring on Various Dates Through Fiscal 2017
Debt Instrument [Line Items]
Other committed and uncommitted lines of credit and overdraft facilities	$ 780,600,000