Shareholders' Equity (Tables)

3 Months Ended

Apr. 30, 2012

Shareholders' Equity [Abstract]

Company's Common Share Repurchases And Issuance Activity

	Shares	Weighted- average price per share
Treasury stock held at January 31, 2012........................................................................................................................	18,166,761	$40.71
Shares of common stock repurchased under share repurchase program and other share repurchases....	853,233	$53.48
Shares of treasury stock reissued............................................................................................................................	(458,099)
Treasury stock held at April 30, 2012..............................................................................................................................	18,561,895	$41.30