FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 3) (USD $) In Thousands, unless otherwise specified	9 Months Ended		12 Months Ended
	Sep. 30, 2014		Dec. 31, 2013
Quantitative information
Investment securities available-for-sale	$ 2,592,667		$ 2,733,797
Fair Value Measurements (Level 3)
Quantitative information
Investment securities available-for-sale	8,909		6,371
Derivatives liabilities	3,426		3,655
Corporate debt securities | Non-investment grade
Quantitative information
Investment securities available-for-sale	17,776	[1]	15,101	[1]
Fair Value, Measurements, Recurring | Fair Value Measurements (Level 3)
Quantitative information
Investment securities available-for-sale	8,909		6,371
Derivatives liabilities	3,426		3,655
Fair Value, Measurements, Recurring | Derivative liabilities | Discount cash flow | Low end of range
Quantitative information
Credit risk	0.035%		0.175%
Fair Value, Measurements, Recurring | Derivative liabilities | Discount cash flow | High end of range
Quantitative information
Credit risk	0.046%		0.212%
Fair Value, Measurements, Recurring | Derivative liabilities | Discount cash flow | Weighted Average
Quantitative information
Credit risk	0.043%		0.20%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Fair Value Measurements (Level 3)
Quantitative information
Investment securities available-for-sale	$ 8,909		$ 6,371
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discount cash flow | Low end of range
Quantitative information
Constant prepayment rate	0.00%		0.00%
Constant default rate	0.75%		0.75%
Loss severity	85.00%		85.00%
Discount margin	4.50%		6.50%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discount cash flow | High end of range
Quantitative information
Constant prepayment rate	1.00%		1.00%
Constant default rate	1.20%		1.20%
Loss severity	100.00%		100.00%
Discount margin	9.50%		11.50%
Fair Value, Measurements, Recurring | Corporate debt securities | Non-investment grade | Discount cash flow | Weighted Average
Quantitative information
Constant prepayment rate	0.73%		0.74%
Constant default rate	0.87%		0.87%
Loss severity	85.00%		85.00%
Discount margin	7.99%		9.97%

[1] Investment securities rated BBB- or higher by S&P or Baa3 or higher by Moody's are considered investment grade. Conversely, investment securities rated lower than BBB- by S&P or lower than Baa3 by Moody's are considered non-investment grade.