NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES, Credit Quality Indicator (Details) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Credit Quality Indicators [Abstract]
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 (in months)	6M
Decrease in non-covered loans graded Substandard and Doubtful	$ 133,500,000
Percentage decrease in non-covered loans graded Substandard and Doubtful (in hundredths)	19.00%
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	9,807,250,000	8,717,388,000
Residential [Member] | Single-family [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	1,483,509,000	1,076,281,000
Residential [Member] | Multifamily [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	811,509,000	789,631,000
Commercial Real Estate [Member] | Income Producing [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	3,175,101,000	3,054,197,000
Commercial Real Estate [Member] | Construction [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	134,865,000	202,385,000
Commercial Real Estate [Member] | Land CRE [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	117,471,000	146,499,000
Commercial and Industrial [Member] | Commercial Business [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	2,421,858,000	1,553,218,000
Commercial and Industrial [Member] | Trade Finance [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	447,734,000	296,430,000
Consumer [Member] | Student Loans [Member] | Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	243,292,000	490,314,000
Consumer [Member] | Pass/Watch [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	255,864,000	238,964,000
Pass/Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	9,091,203,000	7,847,919,000
Residential [Member] | Single-family [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	11,780,000	12,376,000
Residential [Member] | Multifamily [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	20,815,000	42,887,000
Commercial Real Estate [Member] | Income Producing [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	81,370,000	80,714,000
Commercial Real Estate [Member] | Construction [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Commercial Real Estate [Member] | Land CRE [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	7,998,000	4,656,000
Commercial and Industrial [Member] | Commercial Business [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	32,461,000	34,449,000
Commercial and Industrial [Member] | Trade Finance [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	6,210,000	4,069,000
Consumer [Member] | Student Loans [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Consumer [Member] | Special Mention [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	127,000	1,486,000
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	160,761,000	180,637,000
Residential [Member] | Single-family [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	22,665,000	30,367,000
Residential [Member] | Multifamily [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	110,104,000	142,227,000
Commercial Real Estate [Member] | Income Producing [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	202,530,000	258,073,000
Commercial Real Estate [Member] | Construction [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	58,123,000	75,662,000
Commercial Real Estate [Member] | Land CRE [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	53,683,000	84,552,000
Commercial and Industrial [Member] | Commercial Business [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	87,162,000	81,185,000
Commercial and Industrial [Member] | Trade Finance [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	15,895,000	8,158,000
Consumer [Member] | Student Loans [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Consumer [Member] | Substandard [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	4,292,000	2,762,000
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	554,454,000	682,986,000
Residential [Member] | Single-family [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Residential [Member] | Multifamily [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Commercial Real Estate [Member] | Income Producing [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Commercial Real Estate [Member] | Construction [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Commercial Real Estate [Member] | Land CRE [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Commercial and Industrial [Member] | Commercial Business [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	832,000	5,846,000
Commercial and Industrial [Member] | Trade Finance [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Consumer [Member] | Student Loans [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Consumer [Member] | Doubtful [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	0	0
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	832,000	5,846,000
Residential [Member] | Single-family [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	1,517,954,000	1,119,024,000
Residential [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	942,428,000	974,745,000
Commercial Real Estate [Member] | Income Producing [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	3,459,001,000	3,392,984,000
Commercial Real Estate [Member] | Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	192,988,000	278,047,000
Commercial Real Estate [Member] | Land CRE [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	179,152,000	235,707,000
Commercial and Industrial [Member] | Commercial Business [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	2,542,313,000	1,674,698,000
Commercial and Industrial [Member] | Trade Finance [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	469,839,000	308,657,000
Consumer [Member] | Student Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	243,292,000	490,314,000
Consumer [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	$ 260,283,000	$ 243,212,000