LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES (Details 3) - Loans Receivable - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 24,236,216	$ 23,659,761
CRE
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,476,682	8,110,749
CRE | Income producing
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,812,733	7,478,474
CRE | Construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	522,967	438,671
CRE | Land
Financing Receivable, Recorded Investment [Line Items]
Total loans	140,982	193,604
C&I
Financing Receivable, Recorded Investment [Line Items]
Total loans	9,163,804	9,003,007
C&I | Commercial business
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,449,136	8,213,897
C&I | Trade finance
Financing Receivable, Recorded Investment [Line Items]
Total loans	714,668	789,110
Residential
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,532,300	4,589,914
Residential | Single-family
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,186,031	3,066,919
Residential | Multifamily
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,346,269	1,522,995
Consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,063,430	1,956,091
Non-PCI Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	23,442,173	22,689,007
Non-PCI Loans | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	22,629,016	21,910,821
Non-PCI Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	206,976	287,530
Non-PCI Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	571,578	466,129
Non-PCI Loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	34,603	24,527
Non-PCI Loans | CRE
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,025,630	7,561,384
Non-PCI Loans | CRE | Income producing
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,364,321	6,937,199
Non-PCI Loans | CRE | Income producing | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,086,172	6,672,951
Non-PCI Loans | CRE | Income producing | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	51,802	59,309
Non-PCI Loans | CRE | Income producing | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	226,347	204,939
Non-PCI Loans | CRE | Income producing | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI Loans | CRE | Construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	522,967	436,776
Non-PCI Loans | CRE | Construction | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	519,345	435,112
Non-PCI Loans | CRE | Construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,622	1,194
Non-PCI Loans | CRE | Construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	470
Non-PCI Loans | CRE | Construction | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI Loans | CRE | Land
Financing Receivable, Recorded Investment [Line Items]
Total loans	138,342	187,409
Non-PCI Loans | CRE | Land | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	124,379	172,189
Non-PCI Loans | CRE | Land | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI Loans | CRE | Land | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	13,953	15,220
Non-PCI Loans | CRE | Land | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	10	0
Non-PCI Loans | C&I
Financing Receivable, Recorded Investment [Line Items]
Total loans	9,117,182	8,943,791
Non-PCI Loans | C&I | Commercial business
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,402,526	8,155,991
Non-PCI Loans | C&I | Commercial business | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,998,058	7,794,735
Non-PCI Loans | C&I | Commercial business | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	139,189	201,280
Non-PCI Loans | C&I | Commercial business | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	234,391	135,449
Non-PCI Loans | C&I | Commercial business | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	30,888	24,527
Non-PCI Loans | C&I | Trade finance
Financing Receivable, Recorded Investment [Line Items]
Total loans	714,656	787,800
Non-PCI Loans | C&I | Trade finance | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	688,080	750,144
Non-PCI Loans | C&I | Trade finance | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,600	13,812
Non-PCI Loans | C&I | Trade finance | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	21,271	23,844
Non-PCI Loans | C&I | Trade finance | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,705	0
Non-PCI Loans | Residential
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,257,575	4,252,004
Non-PCI Loans | Residential | Single-family
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,027,217	2,877,286
Non-PCI Loans | Residential | Single-family | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,002,316	2,841,722
Non-PCI Loans | Residential | Single-family | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,035	8,134
Non-PCI Loans | Residential | Single-family | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	17,866	27,430
Non-PCI Loans | Residential | Single-family | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI Loans | Residential | Multifamily
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,230,358	1,374,718
Non-PCI Loans | Residential | Multifamily | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,177,818	1,317,550
Non-PCI Loans | Residential | Multifamily | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	2,918
Non-PCI Loans | Residential | Multifamily | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	52,540	54,250
Non-PCI Loans | Residential | Multifamily | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI Loans | Consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,041,786	1,931,828
Non-PCI Loans | Consumer | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,032,848	1,926,418
Non-PCI Loans | Consumer | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,728	883
Non-PCI Loans | Consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,210	4,527
Non-PCI Loans | Consumer | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	794,043	970,754
PCI Loans | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	679,106	835,890
PCI Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	17,193	7,551
PCI Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	97,744	127,313
PCI Loans | CRE
Financing Receivable, Recorded Investment [Line Items]
Total loans	451,052	549,365
PCI Loans | CRE | Income producing
Financing Receivable, Recorded Investment [Line Items]
Total loans	448,412	541,275
PCI Loans | CRE | Income producing | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	363,469	440,100
PCI Loans | CRE | Income producing | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	10,866	4,987
PCI Loans | CRE | Income producing | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	74,077	96,188
PCI Loans | CRE | Construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	1,895
PCI Loans | CRE | Construction | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | CRE | Construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | CRE | Construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	1,895
PCI Loans | CRE | Land
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,640	6,195
PCI Loans | CRE | Land | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,248	4,285
PCI Loans | CRE | Land | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | CRE | Land | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	392	1,910
PCI Loans | C&I
Financing Receivable, Recorded Investment [Line Items]
Total loans	46,622	59,216
PCI Loans | C&I | Commercial business
Financing Receivable, Recorded Investment [Line Items]
Total loans	46,610	57,906
PCI Loans | C&I | Commercial business | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	37,284	52,212
PCI Loans | C&I | Commercial business | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,648	819
PCI Loans | C&I | Commercial business | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,678	4,875
PCI Loans | C&I | Trade finance
Financing Receivable, Recorded Investment [Line Items]
Total loans	12	1,310
PCI Loans | C&I | Trade finance | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	12	1,310
PCI Loans | C&I | Trade finance | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | C&I | Trade finance | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | Residential
Financing Receivable, Recorded Investment [Line Items]
Total loans	274,725	337,910
PCI Loans | Residential | Single-family
Financing Receivable, Recorded Investment [Line Items]
Total loans	158,814	189,633
PCI Loans | Residential | Single-family | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	155,941	184,092
PCI Loans | Residential | Single-family | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,227	1,293
PCI Loans | Residential | Single-family | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,646	4,248
PCI Loans | Residential | Multifamily
Financing Receivable, Recorded Investment [Line Items]
Total loans	115,911	148,277
PCI Loans | Residential | Multifamily | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	99,886	130,770
PCI Loans | Residential | Multifamily | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | Residential | Multifamily | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	16,025	17,507
PCI Loans | Consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	21,644	24,263
PCI Loans | Consumer | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	20,266	23,121
PCI Loans | Consumer | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	452	452
PCI Loans | Consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 926	$ 690