Shareholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended			158 Months Ended
	Oct. 31, 2008	Jan. 31, 2008	Mar. 04, 2017	Feb. 27, 2016	Feb. 28, 2015	Mar. 04, 2017	Feb. 28, 2004
Class of Stock [Line Items]
Junior preferred stock, shares			200,000			200,000
Junior preferred stock par value			$ 1.00			$ 1.00
Share repurchases, shares			(250,000)	575,000	203,000
Stock Based Compensation Plans
Class of Stock [Line Items]
Adjustments Related to Tax Withholding for Share-based Compensation			$ 2.6	$ 5.1	$ 5.2
Share Repurchase Program
Class of Stock [Line Items]
Number of shares authorized under share repurchase program							1,500,000
Increase in authorized shares under the share repurchase program	1,000,000	750,000	1,000,000
Share repurchases, shares			250,001	575,000	203,509	3,307,633
Share repurchases, value			$ 10.8	$ 24.9	$ 6.9	$ 72.3
Remaining shares authorized to be repurchased			942,367,000			942,367,000