LOANS RECEIVABLE AND THE ALLOWANCE FOR LOAN LOSSES (Fixed-rate and Adjustable-Rate Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Fixed-rate (term to maturity):
Maturing in one year or less	$ 142,073	$ 115,571
Maturing after one year through three years	221,958	184,707
Maturing after three years through five years	175,126	180,449
Maturing after five years through ten years	253,935	240,742
Maturing after ten years	495,890	572,793
Total fixed-rate loans	1,288,982	1,294,262
Adjustable-Rate (term to rate adjustment):
Maturing or repricing in one year or less	1,596,440	1,468,316
Maturing or repricing after one year through three years	569,449	416,433
Maturing or repricing after three years through five years	577,185	566,371
Maturing or repricing after five years through ten years	158,566	87,506
Maturing or repricing after ten years	55,854	932
Total adjustable-rate loans	2,957,494	2,539,558
Total loans	$ 4,246,476	$ 3,833,820	$ 3,762,599