Shareholders' Equity (Company's Common Share Repurchase And Issuance Activity) (Details) - $ / shares	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018
Increase (Decrease) in Treasury Stock
Treasury stock, beginning balance, Shares	21,083,972	24,018,983
Stock Repurchased During Period, Shares	1,429,154	0
Shares of treasury stock reissued for equity incentive plans	(207,662)	(149,609)
Shares of treasury stock reissued for acquisition of TS		(2,785,402)
Treasury stock, ending balance, Shares	22,305,464	21,083,972
Treasury Stock Acquired, Average Cost Per Share	$ 74.89
Treasury stock, beginning balance, Weighted-average price per share	44.59	$ 44.59
Treasury stock, ending balance, Weighted-average price per share	$ 46.53	$ 44.59