FAIR VALUE (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Financial Liabilities
Other borrowings	$ 20,000
Estimated Fair Value
Financial Assets
Cash and cash equivalents	1,323,106	1,431,185
Short-term investments	366,378	61,834
Securities purchased under resale agreements	1,442,302	791,745
Loans held for sale	180,349	285,181
Loans receivable, net	14,743,218	13,520,712
Investment in Federal Home Loan Bank stock	107,275	136,897
Investment in Federal Reserve Bank stock	48,003	47,512
Accrued interest receivable	94,837	89,686
Financial Liabilities
Demand, savings and money market deposits	12,187,740	10,307,001
Time deposits	6,115,530	7,194,125
Federal Home Loan Bank advances	333,060	479,029
Securities sold under repurchase agreements	1,173,830	1,177,331
Other borrowings	20,000
Accrued interest payable	10,855	15,447
Long-term debt	83,762	144,392
Level 1
Financial Assets
Cash and cash equivalents	1,323,106	1,431,185
Level 2
Financial Assets
Short-term investments	366,378	61,834
Securities purchased under resale agreements	1,442,302	791,745
Loans held for sale	180,349	285,181
Investment in Federal Home Loan Bank stock	107,275	136,897
Investment in Federal Reserve Bank stock	48,003	47,512
Accrued interest receivable	94,837	89,686
Financial Liabilities
Demand, savings and money market deposits	12,187,740	10,307,001
Federal Home Loan Bank advances	333,060	479,029
Securities sold under repurchase agreements	1,173,830	1,177,331
Other borrowings	20,000
Accrued interest payable	10,855	15,447
Long-term debt	83,762	144,392
Level 3
Financial Assets
Loans receivable, net	14,743,218	13,520,712
Financial Liabilities
Time deposits	$ 6,115,530	$ 7,194,125