Debt Debt (Other Facilities) (Details) - USD ($)	Oct. 31, 2015	Jan. 31, 2015	Sep. 21, 2012
Debt Instrument
Line of Credit, Current	$ 16,744,000
Standby Letters Of Credit	65,196,000
Line of Credit Facility, Current Borrowing Capacity	743,700,000
Accounts Receivable, Net, Current	2,926,554,000	$ 2,811,963,000
Credit Agreement
Debt Instrument
Line Of Credit Facility Possible Future Increase To Maximum Borrowing Capacity	750,000,000
Line of Credit, Amount Outstanding	0	0
Line of Credit Facility, Maximum Borrowing Capacity	500,000,000
Receivables Securitization Program
Debt Instrument
Line of Credit, Amount Outstanding	0	0
Line of Credit Facility, Maximum Borrowing Capacity	400,000,000
Accounts Receivable, Net, Current	805,572,000	594,900,000
Other Committed And Uncommitted Revolving Credit Facilities Expiring on Various Dates Through Fiscal Two Thousand and Seventeen [Member]
Debt Instrument
Line of Credit, Current	$ 16,744,000	$ 12,848,000
Line of Credit Facility, Interest Rate at Period End	5.13%	4.97%
Line of Credit Facility, Maximum Borrowing Capacity	$ 319,613,000
Senior Notes
Debt Instrument
Debt Instrument, Interest Rate, Stated Percentage	3.75%	3.75%	3.75%