Goodwill And Intangible Assets (Schedule Of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Jan. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 578,074	$ 408,768
Accumulated amortization	308,516	264,197
Net book value	269,558	144,571
Capitalized software and development costs
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	330,116	301,052
Accumulated amortization	248,013	223,148
Net book value	82,103	77,904
Customer and Vendor Relationship
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	206,415	98,080
Accumulated amortization	52,608	36,544
Net book value	153,807	61,536
Preferred Supplier Agreement
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	30,754	0
Accumulated amortization	1,575	0
Net book value	29,179	0
Other intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	10,789	9,636
Accumulated amortization	6,320	4,505
Net book value	$ 4,469	$ 5,131