INVESTMENT SECURITIES (Details 3) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
INVESTMENT SECURITIES
Gross gains on sale of investment securities	$ 5,300,000	$ 26,300,000	$ 10,900,000	$ 28,000,000
Gross losses on sale of investment securities	0	26,200,000	0	27,400,000
Net income statement impact of gain on sale of investment securities	5,300,000	71,000	10,900,000	554,000
Tax expense on sale of investment securities	2,200,000	30,000	4,600,000	233,000
Net proceeds for sales of investment securities	$ 128,900,000	$ 837,000,000	$ 325,700,000	$ 1,100,000,000