Segment Information (Financial Information By Geographic Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 30, 2012	Apr. 30, 2011	Jan. 31, 2012
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers	$ 5,895,561	$ 6,332,128
Operating income	80,893	75,683
Stock-based compensation expense	(2,780)	(2,467)
Depreciation and amortization	13,397	14,756
Capital expenditures	12,137	7,043
Identifiable assets	5,644,183	6,482,030	5,785,418
Goodwill and acquisition-related intangible assets, net	152,348	130,466
Americas [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers	2,454,371	2,615,805
Operating income	51,062	47,873
Depreciation and amortization	3,782	3,916
Capital expenditures	8,487	3,268
Identifiable assets	1,946,018	2,080,856
Goodwill and acquisition-related intangible assets, net	2,966	2,966
Europe [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers	3,441,190	3,716,323
Operating income	32,611	30,277
Depreciation and amortization	9,615	10,840
Capital expenditures	3,650	3,775
Identifiable assets	3,698,165	4,401,174
Goodwill and acquisition-related intangible assets, net	$ 149,382	$ 127,500