NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 grade	Dec. 31, 2011
Credit Quality Indicators
Number of grades in the risk rating system utilized by the company to rate credit risk of loans receivable	8
Maximum term for a loan to stay graded as Special Mention	6 months
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	$ 10,498,113	$ 10,288,426
Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	9,826,508	9,565,009
Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	173,234	177,548
Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	498,371	545,622
Doubtful
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross		247
Residential
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	2,869,876	2,729,803
Residential | Residential Single-family
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	1,953,123	1,796,635
Residential | Residential Single-family | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	1,926,705	1,768,149
Residential | Residential Single-family | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	10,905	11,239
Residential | Residential Single-family | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	15,513	17,247
Residential | Residential Multifamily
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	916,753	933,168
Residential | Residential Multifamily | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	798,348	810,458
Residential | Residential Multifamily | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	23,930	25,531
Residential | Residential Multifamily | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	94,475	97,179
Commercial Real Estate ("CRE")
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	3,776,874	3,832,365
Commercial Real Estate ("CRE") | Income producing
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	3,454,641	3,487,866
Commercial Real Estate ("CRE") | Income producing | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	3,204,450	3,211,386
Commercial Real Estate ("CRE") | Income producing | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	43,052	63,066
Commercial Real Estate ("CRE") | Income producing | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	207,139	213,414
Commercial Real Estate ("CRE") | Construction
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	152,579	171,410
Commercial Real Estate ("CRE") | Construction | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	110,094	109,184
Commercial Real Estate ("CRE") | Construction | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	42,485	62,226
Commercial Real Estate ("CRE") | Land
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	169,654	173,089
Commercial Real Estate ("CRE") | Land | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	123,089	125,534
Commercial Real Estate ("CRE") | Land | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	7,909	7,954
Commercial Real Estate ("CRE") | Land | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	38,656	39,601
Commercial and Industrial ("C&I")
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	3,238,605	3,142,472
Commercial and Industrial ("C&I") | Commercial Business
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	2,785,971	2,655,917
Commercial and Industrial ("C&I") | Commercial Business | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	2,621,289	2,492,904
Commercial and Industrial ("C&I") | Commercial Business | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	81,050	62,409
Commercial and Industrial ("C&I") | Commercial Business | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	83,632	100,357
Commercial and Industrial ("C&I") | Commercial Business | Doubtful
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross		247
Commercial and Industrial ("C&I") | Trade finance
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	452,634	486,555
Commercial and Industrial ("C&I") | Trade finance | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	435,020	467,822
Commercial and Industrial ("C&I") | Trade finance | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	6,168	7,161
Commercial and Industrial ("C&I") | Trade finance | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	11,446	11,572
Consumer
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	612,758	583,786
Consumer | Student loans
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	341,966	306,325
Consumer | Student loans | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	341,134	305,880
Consumer | Student loans | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	50	188
Consumer | Student loans | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	782	257
Consumer | Other Consumer
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	270,792	277,461
Consumer | Other Consumer | Pass/Watch
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	266,379	273,692
Consumer | Other Consumer | Special Mention
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	170
Consumer | Other Consumer | Substandard
Credit quality indicator disclosures
Loans receivable, excluding covered loans, gross	$ 4,243	$ 3,769