FAIR VALUE (Details 6) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Financial Assets:
Investment securities available-for-sale	$ 2,733,797	$ 2,607,029
Financial Liabilities:
Other borrowings		20,000
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
Carrying Amount or Notional Amount
Financial Assets:
Cash and cash equivalents	895,820	1,323,106
Short-term investments	257,473	366,378
Securities purchased under resale agreements	1,300,000	1,450,000
Investment securities available-for-sale	2,733,797	2,607,029
Loans held for sale	204,970	174,317
Loans receivable, net	17,600,613	14,645,785
Investment in Federal Home Loan Bank stock	62,330	107,275
Investment in Federal Reserve Bank stock	48,333	48,003
Accrued interest receivable	116,314	94,837
Foreign exchange options	85,614	85,614
Interest rate swaps	1,915,474	1,190,793
Foreign exchange contracts	440,848	112,459
Financial Liabilities:
Demand, savings and money market deposits	14,588,570	12,187,740
Time deposits	5,824,348	6,121,614
Federal Home Loan Bank advances	315,092	312,975
Securities sold under repurchase agreements	995,000	995,000
Other borrowings		20,000
Accrued interest payable	11,178	10,855
Long-term debt	226,868	137,178
Derivatives liabilities	2,308,612	1,392,494
Estimated Fair Value
Financial Assets:
Cash and cash equivalents	895,820	1,323,106
Short-term investments	257,473	366,378
Securities purchased under resale agreements	1,279,406	1,442,302
Investment securities available-for-sale	2,733,797	2,607,029
Loans held for sale	212,469	180,349
Loans receivable, net	16,741,674	14,743,218
Investment in Federal Home Loan Bank stock	62,330	107,275
Investment in Federal Reserve Bank stock	48,333	48,003
Accrued interest receivable	116,314	94,837
Foreign exchange options	6,290	5,011
Interest rate swaps	28,078	36,943
Foreign exchange contracts	6,181	896
Financial Liabilities:
Demand, savings and money market deposits	14,588,570	12,187,740
Time deposits	5,791,659	6,115,530
Federal Home Loan Bank advances	308,521	333,060
Securities sold under repurchase agreements	1,134,774	1,173,830
Other borrowings		20,000
Accrued interest payable	11,178	10,855
Long-term debt	184,415	83,762
Derivatives liabilities	$ 50,262	$ 42,060