FAIR VALUE (Details 6) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012 Carrying Amount or Notional Amount	Dec. 31, 2011 Carrying Amount or Notional Amount	Sep. 30, 2012 Estimated Fair Value	Dec. 31, 2011 Estimated Fair Value
Financial Assets
Cash and cash equivalents		$ 1,816,372	$ 1,431,185	$ 1,816,372	$ 1,431,185
Short-term investments		347,001	61,834	347,001	61,834
Federal funds sold	20,000	20,000		20,000
Securities purchased under resale agreements		1,100,000	786,434	1,098,838	791,745
Investment securities available-for-sale		2,237,848	3,072,578	2,237,848	3,072,578
Loans Held for sale		157,869	278,603	163,189	285,181
Loans receivable, net		14,094,971	13,984,930	14,156,103	13,520,712
Investment in Federal Home Loan Bank stock		117,954	136,897	117,954	136,897
Investment in Federal Reserve Bank stock		47,872	47,512	47,872	47,512
Accrued interest receivable		88,814	89,686	88,814	89,686
Equity swap agreements		22,709	22,709	205	202
Foreign exchange options		85,614	85,614	4,371	3,899
Interest rate swaps		1,015,981	585,196	34,059	20,474
Short-term foreign exchange contracts		78,155	210,295	1,118	1,403
Financial Liabilities
Demand, savings and money market deposits		11,369,857	10,307,001	11,369,857	10,307,001
Time deposits		6,296,570	7,146,001	6,273,756	7,194,125
Federal Home Loan Bank advances		363,119	455,251	394,916	479,029
Securities sold under repurchase agreements		995,000	1,020,208	1,193,742	1,177,331
Accrued interest payable		11,209	15,447	11,209	15,447
Long-term debt		137,178	212,178	86,741	144,392
Derivatives liabilities		$ 1,153,402	$ 835,913	$ 38,849	$ 24,164
Maximum term of maturity for securities purchased under resale agreements to be included in cash and cash equivalents	90 days
Term of maturity that securities purchased under resale agreements must exceed to be included in certain fair value calculations	90 days
Maximum term of maturity for carrying amount of securities sold under repurchase agreements to approximate fair value	90 days