FEDERAL HOME LOAN BANK ADVANCES AND OTHER BORROWINGS (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
FEDERAL HOME LOAN BANK ADVANCES AND OTHER BORROWINGS [Abstract]
Advances from Federal Home Loan Banks	$ 83,692	$ 83,700
Federal Home Loan Bank advances, weighted average interest rate (in percent)	1.78%	1.78%
Advances with fixed maturity dates	$ 71,700	$ 71,700
Weighted average interest rate on fixed maturity advances	1.57%	1.57%
Residential mortgages pledged as collateral for advances	$ 428,200	$ 388,500
Multifamily mortgage loans pledged as collateral for advances	1,100,000	815,600
Callable variable rate advances	$ 12,000	$ 12,000
Weighted average interest rate on variable advances (in percent)	3.01%	3.01%
Investment pledges against advances	$ 13,200	$ 13,400
Overnight borrowings of debt	$ 40,700	$ 54,600
Average interest rate of FHLB advances	0.52%	0.32%
Unused commitments from FHLB	$ 885,000
Unused short-term or overnight borrowings from correspondent banks	22,000
Unused short-term or overnight borrowings from FRB	$ 113,900