NON COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 2) (USD $)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Purchased Loans
Loans acquired during the period	$ 782,800,000
Carrying amount of loans acquired	740,800,000
Percentage of purchased loans classified as student loans	89.00%
Loans Held for Sale
Total loans held for sale	278,603,000	220,055,000
Percentage of loans held for sale that were originally reclassified as student loans	90.00%
Loans transferred to loans held for sale	644,915,000	563,974,000
Proceeds from the sales of Loans held for sale, including loans reclassified to loans held for sale	652,700,000	409,500,000	37,100,000
Net gain from sale of loans held for sale during the period	$ 14,500,000	$ 18,500,000
Residential \| Non-Covered and Covered Loans Receivable \| Geographic Concentration \| California
Credit Risk and Concentrations
Percentage of non-covered REO properties	92.00%

The carrying amount of loans acquired during the reporting period.

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Loans acquired during the reporting period.

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Percentage of loans held for sale as of the reporting date that were originally classified as student loans.

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No definition available.

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Represents the percentage of purchased loans classified as student loans.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans and leases that were sold during the reporting period. This element refers to the gain (loss) and not to the cash proceeds of the sales. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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The aggregate carrying amount of loans receivable that will be sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or elected fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).

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The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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