Segment Information - Company's Segments Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013	Jul. 31, 2012
Net sales:
Net sales	$ 925,884	$ 886,569	$ 1,821,368	$ 1,705,739
Earnings (losses) from operations:
Earnings (losses) from operations	206,998	187,597	389,960	352,032
Americas [Member]
Net sales:
Net sales	443,856	433,989	851,553	819,663
Earnings (losses) from operations:
Earnings (losses) from operations	87,731	83,866	146,693	139,807
Asia-Pacific [Member]
Net sales:
Net sales	208,325	174,138	431,752	369,208
Earnings (losses) from operations:
Earnings (losses) from operations	49,882	35,026	105,341	86,086
Japan [Member]
Net sales:
Net sales	136,395	158,663	280,922	300,452
Earnings (losses) from operations:
Earnings (losses) from operations	48,235	50,266	101,654	92,826
Europe [Member]
Net sales:
Net sales	111,247	100,214	204,233	188,121
Earnings (losses) from operations:
Earnings (losses) from operations	22,338	20,597	36,616	37,252
Total reportable segments [Member]
Net sales:
Net sales	899,823	867,004	1,768,460	1,677,444
Earnings (losses) from operations:
Earnings (losses) from operations	208,186	189,755	390,304	355,971
Other [Member]
Net sales:
Net sales	26,061	19,565	52,908	28,295
Earnings (losses) from operations:
Earnings (losses) from operations	$ (1,188)	$ (2,158)	$ (344)	$ (3,939)