Financial Information by Geographic Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2012	Jul. 31, 2011	Jan. 31, 2012
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers:	$ 5,961,500	$ 6,449,461	$ 11,857,061	$ 12,781,589
Operating income:	59,256	78,775	140,149	154,458
Stock-based compensation expense	(3,902)	(2,715)	(6,682)	(5,182)
Depreciation and amortization	13,193	14,187	26,590	28,943
Capital expenditures	8,191	12,004	20,328	19,047
Identifiable assets	5,301,063	6,099,222	5,301,063	6,099,222	5,785,418
Goodwill and acquisition-related intangible assets, net	140,443	125,583	140,443	125,583
Americas [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers:	2,399,839	2,697,655	4,854,210	5,313,460
Operating income:	29,537	47,635	80,599	95,508
Depreciation and amortization	4,039	3,853	7,821	7,769
Capital expenditures	4,204	7,987	12,691	11,255
Identifiable assets	1,793,491	2,320,764	1,793,491	2,320,764
Goodwill and acquisition-related intangible assets, net	2,966	2,966	2,966	2,966
Europe [Member]
Segment Reporting Information [Line Items]
Net sales to unaffiliated customers:	3,561,661	3,751,806	7,002,851	7,468,129
Operating income:	33,621	33,855	66,232	64,132
Depreciation and amortization	9,154	10,334	18,769	21,174
Capital expenditures	3,987	4,017	7,637	7,792
Identifiable assets	3,507,572	3,778,458	3,507,572	3,778,458
Goodwill and acquisition-related intangible assets, net	$ 137,477	$ 122,617	$ 137,477	$ 122,617