INVESTMENT SECURITIES (Other Investments) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Accrued investment income receivable	$ 55.8	$ 55.8	$ 60.5
Stock of FHLB of Pittsburgh and the Federal Reserve Board	828.6	828.6	800.5
FHLB Stock, par value (in usd per share)	$ 100	$ 100
Sale of FHLB stock	$ 11.9	$ 166.0