NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 5) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	$ 28,302		$ 28,302		$ 33,117
Accruing loans 60 - 89 days past due	16,406		16,406		7,210
Total accruing past due loans	44,708		44,708		40,327
Nonaccrual loans less than 90 days past due	20,821		20,821		45,786
Nonaccrual loans 90 or more days past due	83,271		83,271		99,846
Total nonaccrual past due loans	104,092		104,092		145,632
Current loans	11,164,277		11,164,277		10,381,070
Total non-covered loans and loans held for sale, gross	11,313,077		11,313,077		10,567,029
Unearned fees, premiums and discounts, net	(15,185)		(15,185)		(16,762)
Recorded investment in non-covered loans and loans held for sale	11,297,892		11,297,892		10,550,267
Interest Income Foregone on Nonaccrual Loans
Interest income that would have been recognized had nonaccrual loans performed in accordance with their original terms	1,497	2,360	4,994	7,923
Less: Interest income recognized on nonaccrual loans on a cash basis	(633)	(756)	(1,526)	(2,267)
Interest income foregone on nonaccrual loans	864	1,604	3,468	5,656
Loans Held for Sale
Age analysis of past due non-covered loans and loans held for sale
Nonaccrual loans 90 or more days past due	9,642		9,642		25,655
Total nonaccrual past due loans	9,642		9,642		25,655
Current loans	148,227		148,227		252,948
Total non-covered loans and loans held for sale, gross	157,869		157,869		278,603
Residential | Single-family
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	2,998		2,998		6,991
Accruing loans 60 - 89 days past due	7,266		7,266		1,198
Total accruing past due loans	10,264		10,264		8,189
Nonaccrual loans less than 90 days past due	1,010		1,010
Nonaccrual loans 90 or more days past due	7,742		7,742		3,569
Total nonaccrual past due loans	8,752		8,752		3,569
Current loans	2,046,606		2,046,606		1,784,877
Total non-covered loans and loans held for sale, gross	2,065,622		2,065,622		1,796,635
Residential | Multifamily
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	6,005		6,005		6,366
Accruing loans 60 - 89 days past due					745
Total accruing past due loans	6,005		6,005		7,111
Nonaccrual loans less than 90 days past due	11,440		11,440		6,889
Nonaccrual loans 90 or more days past due	11,594		11,594		11,306
Total nonaccrual past due loans	23,034		23,034		18,195
Current loans	882,742		882,742		907,862
Total non-covered loans and loans held for sale, gross	911,781		911,781		933,168
Commercial Real Estate ("CRE") | Income producing
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	14,150		14,150		18,179
Accruing loans 60 - 89 days past due	6,239		6,239		1,549
Total accruing past due loans	20,389		20,389		19,728
Nonaccrual loans less than 90 days past due	3,478		3,478		6,885
Nonaccrual loans 90 or more days past due	7,587		7,587		25,690
Total nonaccrual past due loans	11,065		11,065		32,575
Current loans	3,488,147		3,488,147		3,435,563
Total non-covered loans and loans held for sale, gross	3,519,601		3,519,601		3,487,866
Commercial Real Estate ("CRE") | Construction
Age analysis of past due non-covered loans and loans held for sale
Nonaccrual loans less than 90 days past due					26,482
Nonaccrual loans 90 or more days past due	21,800		21,800		14,688
Total nonaccrual past due loans	21,800		21,800		41,170
Current loans	88,741		88,741		130,240
Total non-covered loans and loans held for sale, gross	110,541		110,541		171,410
Commercial Real Estate ("CRE") | Land
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	661		661
Accruing loans 60 - 89 days past due					573
Total accruing past due loans	661		661		573
Nonaccrual loans less than 90 days past due	652		652		1,136
Nonaccrual loans 90 or more days past due	7,265		7,265		9,589
Total nonaccrual past due loans	7,917		7,917		10,725
Current loans	131,753		131,753		161,791
Total non-covered loans and loans held for sale, gross	140,331		140,331		173,089
Commercial and Industrial ("C&I") | Commercial Business
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	1,465		1,465		342
Accruing loans 60 - 89 days past due	2,382		2,382		2,957
Total accruing past due loans	3,847		3,847		3,299
Nonaccrual loans less than 90 days past due	3,537		3,537		4,394
Nonaccrual loans 90 or more days past due	11,983		11,983		6,843
Total nonaccrual past due loans	15,520		15,520		11,237
Current loans	3,077,904		3,077,904		2,641,381
Total non-covered loans and loans held for sale, gross	3,097,271		3,097,271		2,655,917
Commercial and Industrial ("C&I") | Trade finance
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 60 - 89 days past due	84		84
Total accruing past due loans	84		84
Nonaccrual loans less than 90 days past due	704		704
Nonaccrual loans 90 or more days past due	1,919		1,919
Total nonaccrual past due loans	2,623		2,623
Current loans	632,807		632,807		486,555
Total non-covered loans and loans held for sale, gross	635,514		635,514		486,555
Consumer | Student loans
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	69		69		109
Accruing loans 60 - 89 days past due					188
Total accruing past due loans	69		69		297
Nonaccrual loans 90 or more days past due	69		69		257
Total nonaccrual past due loans	69		69		257
Current loans	405,881		405,881		305,771
Total non-covered loans and loans held for sale, gross	406,019		406,019		306,325
Consumer | Other Consumer
Age analysis of past due non-covered loans and loans held for sale
Accruing loans 30 - 59 days past due	2,954		2,954		1,130
Accruing loans 60 - 89 days past due	435		435
Total accruing past due loans	3,389		3,389		1,130
Nonaccrual loans 90 or more days past due	3,670		3,670		2,249
Total nonaccrual past due loans	3,670		3,670		2,249
Current loans	261,469		261,469		274,082
Total non-covered loans and loans held for sale, gross	$ 268,528		$ 268,528		$ 277,461