FAIR VALUE (Details 5) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011 Carrying Amount or Notional Amount	Dec. 31, 2010 Carrying Amount or Notional Amount	Dec. 31, 2011 Estimated Fair Value	Dec. 31, 2010 Estimated Fair Value
Financial Assets
Cash and cash equivalents		$ 1,431,185	$ 1,333,949	$ 1,431,185	$ 1,333,949
Short-term investments		61,834	143,560	61,834	143,560
Securities purchased under resale agreements		786,434	500,000	791,745	505,826
Investment securities available-for-sale		3,072,578	2,875,941	3,072,578	2,875,941
Loans Held for sale		278,603	220,055	285,181	225,221
Loans receivable, net		13,984,930	13,231,075	13,520,712	13,043,932
Investment in Federal Home Loan Bank stock		136,897	162,805	136,897	162,805
Investment in Federal Reserve Bank stock		47,512	47,285	47,512	47,285
Accrued interest receivable		89,686	82,090	89,686	82,090
Equity swap agreements		22,709	22,884	202	206
Foreign exchange options		85,614	85,614	3,899	5,084
Interest rate swaps		585,196	4,098	20,474	13
Short-term foreign exchange contracts		210,295	92,625	1,403	1,220
Financial Liabilities
Demand, savings and money market deposits		10,307,001	8,875,806	10,307,001	8,875,806
Time deposits		7,146,001	6,765,453	7,194,125	6,762,892
Federal funds purchased			22		22
Federal Home Loan Bank advances		455,251	1,214,148	479,029	1,199,151
Securities sold under repurchase agreements		1,020,208	1,083,545	1,177,331	1,296,522
Notes payable		85,987	49,690	85,987	49,690
Accrued interest payable		15,447	13,797	15,447	13,797
Long-term debt		212,178	235,570	144,392	125,633
Derivatives liabilities		$ 835,913	$ 130,752	$ 24,164	$ 4,498
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