LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Allowance for loan losses		$ (261,229)		$ (261,679)
Loans, net	[1]	21,697,435		21,468,270
Non-PCI loans
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans, net		20,526,245		20,146,871
PCI loans
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans, net	[1]	1,171,190		1,321,399
Loans Receivable
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	21,964,612		21,727,145
Unearned fees, premiums and discounts, net		(5,948)		2,804
Allowance for loan losses		(261,229)	$ (257,738)	(261,679)	$ (251,348)	$ (252,136)	$ (249,675)
Loans Receivable | CRE
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	7,286,873		6,819,513
Loans Receivable | CRE | Income producing
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	6,714,165		6,256,059
Loans Receivable | CRE | Construction
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	377,774		332,287
Loans Receivable | CRE | Land
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	194,934		231,167
Loans Receivable | C&I
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	8,150,664		8,077,201
Loans Receivable | C&I | Commercial business
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	7,377,605		7,181,189
Loans Receivable | C&I | Trade finance
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	773,059		896,012
Loans Receivable | Residential
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	4,797,632		5,316,689
Loans Receivable | Residential | Single-family
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	3,323,152		3,866,781
Loans Receivable | Residential | Multifamily
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	1,474,480		1,449,908
Loans Receivable | Consumer
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	1,729,443		1,513,742
Loans Receivable | Non-PCI loans
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		20,792,810		20,405,032
Unearned fees, premiums and discounts, net		(5,948)		2,804
Allowance for loan losses		(260,617)	(257,095)	(260,965)	(249,790)	(249,934)	(247,406)
Loans Receivable | Non-PCI loans | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		20,024,124		19,625,603
Loans Receivable | Non-PCI loans | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		237,566		213,007
Loans Receivable | Non-PCI loans | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		527,353		565,834
Loans Receivable | Non-PCI loans | Doubtful
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		3,767		533
Loans Receivable | Non-PCI loans | Loss
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans				55
Loans Receivable | Non-PCI loans | CRE
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		6,640,321		6,102,216
Allowance for loan losses		(75,496)	(69,740)	(72,263)	(60,895)	(63,627)	(70,154)
Loans Receivable | Non-PCI loans | CRE | Income producing
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		6,087,661		5,568,046
Loans Receivable | Non-PCI loans | CRE | Income producing | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		5,810,946		5,243,640
Loans Receivable | Non-PCI loans | CRE | Income producing | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		48,382		54,673
Loans Receivable | Non-PCI loans | CRE | Income producing | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		228,333		269,733
Loans Receivable | Non-PCI loans | CRE | Construction
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		370,323		319,843
Loans Receivable | Non-PCI loans | CRE | Construction | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		366,869		310,259
Loans Receivable | Non-PCI loans | CRE | Construction | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans				11
Loans Receivable | Non-PCI loans | CRE | Construction | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		3,454		9,573
Loans Receivable | Non-PCI loans | CRE | Land
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		182,337		214,327
Loans Receivable | Non-PCI loans | CRE | Land | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		159,751		185,220
Loans Receivable | Non-PCI loans | CRE | Land | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans				5,701
Loans Receivable | Non-PCI loans | CRE | Land | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		22,586		23,406
Loans Receivable | Non-PCI loans | C&I
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		8,079,552		7,987,581
Allowance for loan losses		(133,962)	(133,914)	(134,598)	(131,057)	(127,156)	(115,184)
Loans Receivable | Non-PCI loans | C&I | Commercial business
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		7,311,273		7,097,853
Loans Receivable | Non-PCI loans | C&I | Commercial business | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		6,978,635		6,836,914
Loans Receivable | Non-PCI loans | C&I | Commercial business | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		162,020		130,319
Loans Receivable | Non-PCI loans | C&I | Commercial business | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		166,851		130,032
Loans Receivable | Non-PCI loans | C&I | Commercial business | Doubtful
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		3,767		533
Loans Receivable | Non-PCI loans | C&I | Commercial business | Loss
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans				55
Loans Receivable | Non-PCI loans | C&I | Trade finance
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		768,279		889,728
Loans Receivable | Non-PCI loans | C&I | Trade finance | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		726,648		845,889
Loans Receivable | Non-PCI loans | C&I | Trade finance | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		19,193		13,031
Loans Receivable | Non-PCI loans | C&I | Trade finance | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		22,438		30,808
Loans Receivable | Non-PCI loans | Residential
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		4,370,115		4,831,279
Allowance for loan losses		(40,668)	(42,990)	(43,856)	(45,949)	(47,995)	(50,716)
Loans Receivable | Non-PCI loans | Residential | Single-family
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		3,119,679		3,647,262
Loans Receivable | Non-PCI loans | Residential | Single-family | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		3,095,832		3,627,491
Loans Receivable | Non-PCI loans | Residential | Single-family | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		5,627		3,143
Loans Receivable | Non-PCI loans | Residential | Single-family | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		18,220		16,628
Loans Receivable | Non-PCI loans | Residential | Multifamily
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		1,250,436		1,184,017
Loans Receivable | Non-PCI loans | Residential | Multifamily | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		1,186,826		1,095,982
Loans Receivable | Non-PCI loans | Residential | Multifamily | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		985		5,124
Loans Receivable | Non-PCI loans | Residential | Multifamily | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		62,625		82,911
Loans Receivable | Non-PCI loans | Consumer
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		1,702,822		1,483,956
Allowance for loan losses		(10,491)	(10,451)	(10,248)	(11,889)	(11,156)	(11,352)
Loans Receivable | Non-PCI loans | Consumer | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		1,698,617		1,480,208
Loans Receivable | Non-PCI loans | Consumer | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		1,359		1,005
Loans Receivable | Non-PCI loans | Consumer | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		2,846		2,743
Loans Receivable | PCI loans
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	1,171,802		1,322,113
Allowance for loan losses		(612)	$ (643)	(714)	$ (1,558)	$ (2,202)	$ (2,269)
Loans Receivable | PCI loans | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		995,270		1,089,726
Loans Receivable | PCI loans | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		9,584		18,688
Loans Receivable | PCI loans | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		166,948		213,699
Loans Receivable | PCI loans | CRE
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	646,552		717,297
Loans Receivable | PCI loans | CRE | Income producing
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	626,504		688,013
Loans Receivable | PCI loans | CRE | Income producing | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		505,872		534,015
Loans Receivable | PCI loans | CRE | Income producing | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		6,920		9,960
Loans Receivable | PCI loans | CRE | Income producing | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		113,712		144,038
Loans Receivable | PCI loans | CRE | Construction
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	7,451		12,444
Loans Receivable | PCI loans | CRE | Construction | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		584		589
Loans Receivable | PCI loans | CRE | Construction | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans				1,744
Loans Receivable | PCI loans | CRE | Construction | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		6,867		10,111
Loans Receivable | PCI loans | CRE | Land
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	12,597		16,840
Loans Receivable | PCI loans | CRE | Land | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		10,333		7,012
Loans Receivable | PCI loans | CRE | Land | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans				5,391
Loans Receivable | PCI loans | CRE | Land | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		2,264		4,437
Loans Receivable | PCI loans | C&I
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	71,112		89,620
Loans Receivable | PCI loans | C&I | Commercial business
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	66,332		83,336
Loans Receivable | PCI loans | C&I | Commercial business | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		58,216		70,586
Loans Receivable | PCI loans | C&I | Commercial business | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		930		1,103
Loans Receivable | PCI loans | C&I | Commercial business | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		7,186		11,647
Loans Receivable | PCI loans | C&I | Trade finance
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	4,780		6,284
Loans Receivable | PCI loans | C&I | Trade finance | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		3,073		4,620
Loans Receivable | PCI loans | C&I | Trade finance | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		1,707		1,664
Loans Receivable | PCI loans | Residential
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	427,517		485,410
Loans Receivable | PCI loans | Residential | Single-family
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	203,473		219,519
Loans Receivable | PCI loans | Residential | Single-family | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		198,113		213,829
Loans Receivable | PCI loans | Residential | Single-family | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		957		374
Loans Receivable | PCI loans | Residential | Single-family | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		4,403		5,316
Loans Receivable | PCI loans | Residential | Multifamily
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	224,044		265,891
Loans Receivable | PCI loans | Residential | Multifamily | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		193,061		230,049
Loans Receivable | PCI loans | Residential | Multifamily | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		664
Loans Receivable | PCI loans | Residential | Multifamily | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		30,319		35,842
Loans Receivable | PCI loans | Consumer
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans	[1]	26,621		29,786
Loans Receivable | PCI loans | Consumer | Pass/Watch
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		26,018		29,026
Loans Receivable | PCI loans | Consumer | Special Mention
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		113		116
Loans Receivable | PCI loans | Consumer | Substandard
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Total loans		$ 490		$ 644

[1] Loans net of ASC 310-30 discount.