CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (USD $)	12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Statement of Comprehensive Income [Abstract]
Net earnings	$ 181,369,000	$ 416,157,000	$ 439,190,000
Other comprehensive (loss) earnings, net of tax
Foreign currency translation adjustments	(27,218,000)	(5,145,000)	7,794,000
Unrealized gain (loss) on marketable securities	828,000	1,719,000	(12,000)
Unrealized (loss) gain on hedging instruments	(3,400,000)	5,522,000	(7,537,000)
Net unrealized gain (loss) on benefit plans	65,117,000	(10,841,000)	(72,810,000)
Other comprehensive earnings (loss), net of tax	35,327,000	(8,745,000)	(72,565,000)
Comprehensive earnings	$ 216,696,000	$ 407,412,000	$ 366,625,000