SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE (REPOs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2010
SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE (REPOs) [Abstract]
Balance outstanding at end of period	$ 0		$ 195,000	$ 195,000
Average interest cost at end of period	0.00%		4.33%	4.33%
Average balance outstanding during period	132,910		195,000	203,055
Average interest cost during the period (in hundredths)	26.24%	[1]	4.33%	4.33%
Estimated fair value of underlying collateral	0		214,446	214,539
Maximum balance outstanding at month end during the year	$ 195,000		$ 195,000	$ 230,000

[1] (a) 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.