NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	$ 13,525,914	$ 11,958,873
Unearned fees, premiums and discounts, net	(28,219)	(19,301)
Allowance for non-covered loans receivable	(233,480)	(229,382)
Non-covered loans receivable, excluding covered loans, net	13,264,215	11,710,190
Residential
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	3,505,842	3,088,031
Residential | Single-family
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	2,575,975	2,187,323
Residential | Multifamily
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	929,867	900,708
Commercial Real Estate ("CRE")
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	4,150,384	3,894,695
Commercial Real Estate ("CRE") | Income producing
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	3,917,082	3,644,035
Commercial Real Estate ("CRE") | Construction
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	105,084	121,589
Commercial Real Estate ("CRE") | Land
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	128,218	129,071
Commercial and Industrial ("C&I")
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	4,709,675	4,231,265
Commercial and Industrial ("C&I") | Commercial Business
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	4,036,795	3,569,388
Commercial and Industrial ("C&I") | Trade finance
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	672,880	661,877
Consumer
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	1,160,013	744,882
Consumer | Student loans
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	615,707	475,799
Consumer | Other Consumer
Non-Covered loans receivable disclosures
Loans receivable, excluding covered loans, gross	$ 544,306	$ 269,083