STOCKHOLDERS' EQUITY (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended	9 Months Ended		0 Months Ended	1 Months Ended	0 Months Ended		1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Jun. 30, 2013	Sep. 30, 2013	Sep. 30, 2012	May 01, 2013 Series A Non-Cumulative Perpetual Convertible Preferred Stock	Apr. 30, 2008 Series A Non-Cumulative Perpetual Convertible Preferred Stock	Jul. 17, 2013 Common Stock	Jan. 23, 2013 Common Stock	Jul. 31, 2013 Common Stock	Sep. 30, 2013 Common Stock	Sep. 30, 2013 Common Stock
Class of Stock
Number of shares issued during the period							200,000
Preferred stock dividend rate (as a percent)							8.00%
Preferred stock liquidation preference (in dollars per share)							$ 1,000
Proceeds from issuance of convertible preferred stock							$ 194.1
Preferred shares converted						85,710
Common stock issued on conversion of convertible preferred stock						5,594,080
Amount of stock repurchase approved by the Board of Directors								100.0	200.0
Purchase of treasury stock pursuant to the Stock Repurchase Program, shares			8,026,807	8,026,807	9,068,105
Weighted average price of shares repurchased (in dollars per share)			$ 24.89		$ 22.02
Total cost of repurchase of treasury shares		199.9	200.0		199.9
Quarterly Dividends
Dividend per share (in dollars per share)	$ 0.15	$ 0.10		$ 0.45	$ 0.30					$ 0.15
Common stock cash dividends paid											$ 20.8	$ 62.5