LOANS RECEIVABLE AND THE ALLOWANCE FOR LOAN LOSSES (Fixed-rate and Adjustable-Rate Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Fixed-rate (term to maturity):
Maturing in one year or less	$ 150,889
Maturing after one year through three years	203,434
Maturing after three years through five years	165,674
Maturing after five years through ten years	272,660
Maturing after ten years	482,673
Total fixed-rate loans	1,275,330
Adjustable-Rate (term to rate adjustment):
Maturing or repricing in one year or less	1,631,649
Maturing or repricing after one year through three years	606,056
Maturing or repricing after three years through five years	605,590
Maturing or repricing after five years through ten years	225,164
Maturing or repricing after ten years	28,805
Total adjustable-rate loans	3,097,264
Total loans	$ 4,372,594	$ 3,833,820	$ 3,806,695