SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE (REPOs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE (REPOs) [Abstract]
Balance outstanding at end of period	$ 0	$ 0	$ 0
Average interest cost at end of period (in hundredths)	0.00%	0.00%	0.00%
Average balance outstanding during period	0	0	132,910
Average interest cost during the period (in hundredths)	0.00%	0.00%	26.24%	[1]
Estimated fair value of underlying collateral	0	0	0
Maximum balance outstanding at month end during the year	0	0	195,000
Prepayment charge included in interest expense	$ 0	$ 0	$ 28,772
Average interest cost related to prepayment charge (in hundredths)	0.00%	0.00%	4.33%

[1] Excluding a prepayment charge of $28,772 included in interest expense on borrowed funds in the consolidated statements of operations, the average interest cost would have been 4.33% during the year ended December 31, 2012.