FAIR VALUE (Details 7) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Financial Assets
Federal funds sold	$ 20,000
Estimated Fair Value
Financial Assets
Cash and cash equivalents	1,816,372	1,431,185
Short-term investments	347,001	61,834
Federal funds sold	20,000
Securities purchased under resale agreements	1,098,838	791,745
Loans Held for sale	163,189	285,181
Loans receivable, net	14,156,103	13,520,712
Investment in Federal Home Loan Bank stock	117,954	136,897
Investment in Federal Reserve Bank stock	47,872	47,512
Accrued interest receivable	88,814	89,686
Financial Liabilities
Demand, savings and money market deposits	11,369,857	10,307,001
Time deposits	6,273,756	7,194,125
Federal Home Loan Bank advances	394,916	479,029
Securities sold under repurchase agreements	1,193,742	1,177,331
Accrued interest payable	11,209	15,447
Long-term debt	86,741	144,392
Level 1
Financial Assets
Cash and cash equivalents	1,816,372	1,431,185
Level 2
Financial Assets
Short-term investments	347,001	61,834
Federal funds sold	20,000
Securities purchased under resale agreements	1,098,838	791,745
Loans Held for sale	163,189	285,181
Investment in Federal Home Loan Bank stock	117,954	136,897
Investment in Federal Reserve Bank stock	47,872	47,512
Accrued interest receivable	88,814	89,686
Financial Liabilities
Demand, savings and money market deposits	11,369,857	10,307,001
Federal Home Loan Bank advances	394,916	479,029
Securities sold under repurchase agreements	1,193,742	1,177,331
Accrued interest payable	11,209	15,447
Long-term debt	86,741	144,392
Level 3
Financial Assets
Loans receivable, net	14,156,103	13,520,712
Financial Liabilities
Time deposits	$ 6,273,756	$ 7,194,125