Consolidated Statement Of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional paid-in capital	Treasury stock	Retained earnings	Accumulated other comprehensive (loss) income
Common Stock, Shares, Issued	59,245,585
Balance at Jan. 31, 2014	$ 2,098,611	$ 89	$ 675,597	$ (894,936)	$ 1,993,290	$ 324,571
Increase (Decrease) in Stockholders' Equity
Purchase of treasury stock, at cost	(52,997)	0	0	(52,997)	0	0
Issuance of treasury stock for benefit plan and equity-based awards exercised	(502)	0	(9,292)	8,790	0	0
Stock-based compensation expense	13,668	0	13,668	0	0	0
Total other comprehensive loss	(273,809)	0	0	0	0	(273,809)
Net income	175,172	0	0	0	175,172	0
Balance at Jan. 31, 2015	$ 1,960,143	89	679,973	(939,143)	2,168,462	50,762
Common Stock, Shares, Issued	59,245,585
Increase (Decrease) in Stockholders' Equity
Purchase of treasury stock, at cost	$ (147,003)	0	0	(147,003)	0	0
Issuance of treasury stock for benefit plan and equity-based awards exercised	(3,924)	0	(12,636)	8,712	0	0
Stock-based compensation expense	14,890	0	14,890	0	0	0
Total other comprehensive loss	(84,087)	0	0	0	0	(84,087)
Net income	265,736	0	0	0	265,736	0
Balance at Jan. 31, 2016	$ 2,005,755	89	682,227	(1,077,434)	2,434,198	(33,325)
Common Stock, Shares, Issued	59,245,585
Increase (Decrease) in Stockholders' Equity
Issuance of treasury stock for benefit plan and equity-based awards exercised	$ (3,692)	0	(10,132)	6,440	0	0
Stock-based compensation expense	13,947	0	13,947	0	0	0
Total other comprehensive loss	(41,217)	0	0	0	0	(41,217)
Net income	195,095	0	0	0	195,095	0
Balance at Jan. 31, 2017	$ 2,169,888	$ 89	$ 686,042	$ (1,070,994)	$ 2,629,293	$ (74,542)
Common Stock, Shares, Issued	59,245,585