LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES (Details 3) (Loans Receivable, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
Nonaccrual and Past Due Loans
Total loans	$ 21,375,568	[1]	$ 21,727,145	[1]
Unearned fees, premiums and discounts, net	(899)	[1]	2,804	[1]
Number of days a loan is past due and is placed on nonaccrual status	90 days
Non-PCI loans
Nonaccrual and Past Due Loans
Accruing loans 30 - 59 days past due	31,659		30,318
Accruing loans 60 - 89 days past due	6,142		9,917
Total accruing past due loans	37,801		40,235
Nonaccrual loans less than 90 days past due	42,105		41,770
Nonaccrual loans 90 or more days past due	45,675		58,492
Total nonaccrual loans	87,780		100,262
Current accruing loans	20,012,001		20,264,535
Total loans	20,137,582		20,405,032
Unearned fees, premiums and discounts, net	(899)		2,804
Total recorded investment in non-PCI loans	20,136,683		20,407,836
CRE
Nonaccrual and Past Due Loans
Total loans	7,045,421	[1]	6,819,513	[1]
CRE | Income producing
Nonaccrual and Past Due Loans
Total loans	6,455,177	[1]	6,256,059	[1]
CRE | Construction
Nonaccrual and Past Due Loans
Total loans	367,460	[1]	332,287	[1]
CRE | Land
Nonaccrual and Past Due Loans
Total loans	222,784	[1]	231,167	[1]
CRE | Non-PCI loans
Nonaccrual and Past Due Loans
Total loans	6,371,041		6,102,216
CRE | Non-PCI loans | Income producing
Nonaccrual and Past Due Loans
Accruing loans 30 - 59 days past due	9,699		14,171
Accruing loans 60 - 89 days past due	1,860		3,593
Total accruing past due loans	11,559		17,764
Nonaccrual loans less than 90 days past due	18,739		19,348
Nonaccrual loans 90 or more days past due	11,011		9,165
Total nonaccrual loans	29,750		28,513
Current accruing loans	5,761,622		5,521,769
Total loans	5,802,931		5,568,046
CRE | Non-PCI loans | Construction
Nonaccrual and Past Due Loans
Nonaccrual loans less than 90 days past due	14		15
Nonaccrual loans 90 or more days past due	917		6,898
Total nonaccrual loans	931		6,913
Current accruing loans	357,187		312,930
Total loans	358,118		319,843
CRE | Non-PCI loans | Land
Nonaccrual and Past Due Loans
Nonaccrual loans less than 90 days past due	214		221
Nonaccrual loans 90 or more days past due	2,386		2,502
Total nonaccrual loans	2,600		2,723
Current accruing loans	207,392		211,604
Total loans	209,992		214,327
C&I
Nonaccrual and Past Due Loans
Total loans	7,720,764	[1]	8,077,201	[1]
C&I | Commercial business
Nonaccrual and Past Due Loans
Total loans	6,871,450	[1]	7,181,189	[1]
C&I | Trade finance
Nonaccrual and Past Due Loans
Total loans	849,314	[1]	896,012	[1]
C&I | Non-PCI loans
Nonaccrual and Past Due Loans
Total loans	7,643,239		7,987,581
C&I | Non-PCI loans | Commercial business
Nonaccrual and Past Due Loans
Accruing loans 30 - 59 days past due	11,227		3,187
Accruing loans 60 - 89 days past due	902		4,361
Total accruing past due loans	12,129		7,548
Nonaccrual loans less than 90 days past due	5,988		6,623
Nonaccrual loans 90 or more days past due	25,436		21,813
Total nonaccrual loans	31,424		28,436
Current accruing loans	6,755,596		7,061,869
Total loans	6,799,149		7,097,853
C&I | Non-PCI loans | Trade finance
Nonaccrual and Past Due Loans
Accruing loans 60 - 89 days past due	600
Total accruing past due loans	600
Nonaccrual loans less than 90 days past due	37		73
Nonaccrual loans 90 or more days past due			292
Total nonaccrual loans	37		365
Current accruing loans	843,453		889,363
Total loans	844,090		889,728
Residential
Nonaccrual and Past Due Loans
Total loans	4,997,219	[1]	5,316,689	[1]
Residential | Single-family
Nonaccrual and Past Due Loans
Total loans	3,512,794	[1]	3,866,781	[1]
Residential | Multifamily
Nonaccrual and Past Due Loans
Total loans	1,484,425	[1]	1,449,908	[1]
Residential | Non-PCI loans
Nonaccrual and Past Due Loans
Total loans	4,539,134		4,831,279
Residential | Non-PCI loans | Single-family
Nonaccrual and Past Due Loans
Accruing loans 30 - 59 days past due	7,239		6,381
Accruing loans 60 - 89 days past due	2,402		1,294
Total accruing past due loans	9,641		7,675
Nonaccrual loans less than 90 days past due	4,731		2,861
Nonaccrual loans 90 or more days past due	4,406		5,764
Total nonaccrual loans	9,137		8,625
Current accruing loans	3,279,997		3,630,962
Total loans	3,298,775		3,647,262
Residential | Non-PCI loans | Multifamily
Nonaccrual and Past Due Loans
Accruing loans 30 - 59 days past due	2,611		4,425
Accruing loans 60 - 89 days past due	376		507
Total accruing past due loans	2,987		4,932
Nonaccrual loans less than 90 days past due	12,216		12,460
Nonaccrual loans 90 or more days past due	1,145		8,359
Total nonaccrual loans	13,361		20,819
Current accruing loans	1,224,011		1,158,266
Total loans	1,240,359		1,184,017
Consumer
Nonaccrual and Past Due Loans
Total loans	1,612,164	[1]	1,513,742	[1]
Consumer | Non-PCI loans
Nonaccrual and Past Due Loans
Accruing loans 30 - 59 days past due	883		2,154
Accruing loans 60 - 89 days past due	2		162
Total accruing past due loans	885		2,316
Nonaccrual loans less than 90 days past due	166		169
Nonaccrual loans 90 or more days past due	374		3,699
Total nonaccrual loans	540		3,868
Current accruing loans	1,582,743		1,477,772
Total loans	$ 1,584,168		$ 1,483,956

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