LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES (Details 3) - Loans Receivable - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 23,767,903	$ 23,659,761
CRE
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,451,478	8,110,749
CRE | Income producing
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,816,442	7,478,474
CRE | Construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	467,103	438,671
CRE | Land
Financing Receivable, Recorded Investment [Line Items]
Total loans	167,933	193,604
C&I
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,818,243	9,003,007
C&I | Commercial business
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,053,535	8,213,897
C&I | Trade finance
Financing Receivable, Recorded Investment [Line Items]
Total loans	764,708	789,110
Residential
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,451,398	4,589,914
Residential | Single-family
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,103,391	3,066,919
Residential | Multifamily
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,348,007	1,522,995
Consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,046,784	1,956,091
Non-PCI loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	22,901,062	22,689,007
Non-PCI loans | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	22,077,967	21,910,821
Non-PCI loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	262,345	287,530
Non-PCI loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	536,943	466,129
Non-PCI loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	23,807	24,527
Non-PCI loans | CRE
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,948,825	7,561,384
Non-PCI loans | CRE | Income producing
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,317,991	6,937,199
Non-PCI loans | CRE | Income producing | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,061,501	6,672,951
Non-PCI loans | CRE | Income producing | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	39,236	59,309
Non-PCI loans | CRE | Income producing | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	217,254	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	465,763	436,776
Non-PCI loans | CRE | Construction | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	462,989	435,112
Non-PCI loans | CRE | Construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,339	1,194
Non-PCI loans | CRE | Construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	435	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	165,071	187,409
Non-PCI loans | CRE | Land | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	150,149	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	14,922	15,220
Non-PCI loans | CRE | Land | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI loans | C&I
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,764,775	8,943,791
Non-PCI loans | C&I | Commercial business
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,001,280	8,155,991
Non-PCI loans | C&I | Commercial business | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,579,392	7,794,735
Non-PCI loans | C&I | Commercial business | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	198,560	201,280
Non-PCI loans | C&I | Commercial business | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	199,521	135,449
Non-PCI loans | C&I | Commercial business | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	23,807	24,527
Non-PCI loans | C&I | Trade finance
Financing Receivable, Recorded Investment [Line Items]
Total loans	763,495	787,800
Non-PCI loans | C&I | Trade finance | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	730,867	750,144
Non-PCI loans | C&I | Trade finance | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	9,907	13,812
Non-PCI loans | C&I | Trade finance | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	22,721	23,844
Non-PCI loans | C&I | Trade finance | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Non-PCI loans | Residential
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,163,941	4,252,004
Non-PCI loans | Residential | Single-family
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,927,219	2,877,286
Non-PCI loans | Residential | Single-family | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,891,346	2,841,722
Non-PCI loans | Residential | Single-family | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,728	8,134
Non-PCI loans | Residential | Single-family | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	28,145	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	1,236,722	1,374,718
Non-PCI loans | Residential | Multifamily | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,185,914	1,317,550
Non-PCI loans | Residential | Multifamily | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,925	2,918
Non-PCI loans | Residential | Multifamily | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	48,883	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	2,023,521	1,931,828
Non-PCI loans | Consumer | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,015,809	1,926,418
Non-PCI loans | Consumer | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,650	883
Non-PCI loans | Consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,062	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	866,841	970,754
PCI Loans | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	742,677	835,890
PCI Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	15,663	7,551
PCI Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	108,501	127,313
PCI Loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | CRE
Financing Receivable, Recorded Investment [Line Items]
Total loans	502,653	549,365
PCI Loans | CRE | Income producing
Financing Receivable, Recorded Investment [Line Items]
Total loans	498,451	541,275
PCI Loans | CRE | Income producing | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	402,651	440,100
PCI Loans | CRE | Income producing | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	13,013	4,987
PCI Loans | CRE | Income producing | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	82,787	96,188
PCI Loans | CRE | Income producing | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | CRE | Construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,340	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	1,340	1,895
PCI Loans | CRE | Construction | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | CRE | Land
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,862	6,195
PCI Loans | CRE | Land | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,272	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	590	1,910
PCI Loans | CRE | Land | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | C&I
Financing Receivable, Recorded Investment [Line Items]
Total loans	53,468	59,216
PCI Loans | C&I | Commercial business
Financing Receivable, Recorded Investment [Line Items]
Total loans	52,255	57,906
PCI Loans | C&I | Commercial business | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	46,426	52,212
PCI Loans | C&I | Commercial business | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,185	819
PCI Loans | C&I | Commercial business | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,644	4,875
PCI Loans | C&I | Commercial business | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | C&I | Trade finance
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,213	1,310
PCI Loans | C&I | Trade finance | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,213	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 | C&I | Trade finance | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | Residential
Financing Receivable, Recorded Investment [Line Items]
Total loans	287,457	337,910
PCI Loans | Residential | Single-family
Financing Receivable, Recorded Investment [Line Items]
Total loans	176,172	189,633
PCI Loans | Residential | Single-family | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	170,788	184,092
PCI Loans | Residential | Single-family | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,013	1,293
PCI Loans | Residential | Single-family | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,371	4,248
PCI Loans | Residential | Single-family | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | Residential | Multifamily
Financing Receivable, Recorded Investment [Line Items]
Total loans	111,285	148,277
PCI Loans | Residential | Multifamily | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	97,447	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	13,838	17,507
PCI Loans | Residential | Multifamily | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
PCI Loans | Consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	23,263	24,263
PCI Loans | Consumer | Pass/Watch
Financing Receivable, Recorded Investment [Line Items]
Total loans	21,880	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	931	690
PCI Loans | Consumer | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 0	$ 0