FAIR VALUE MEASUREMENT AND FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 5) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Covered OREO
Percentage of company's liability for losses under shared loss agreements	20.00%		20.00%		20.00%
Percentage of eligible losses for which the FDIC is obligated to reimburse the Company	80.00%		80.00%		80.00%
Fair Value, Measurements, Nonrecurring
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	(7,035)		(18,875)		(28,012)
Company's liability for losses under shared loss agreements	205		675		2,200
Fair Value, Measurements, Nonrecurring | Non-covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	(1,573)		(1,438)		(5,122)
Fair Value, Measurements, Nonrecurring | Covered OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	(1,027)	[1]	(3,376)	[1]	(11,183)	[1]
Fair Value, Measurements, Nonrecurring | CRE
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	2,196		(4,250)		(8,405)
Fair Value, Measurements, Nonrecurring | C&I
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	(9,169)		(13,135)		(14,540)
Fair Value, Measurements, Nonrecurring | Residential
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	(61)		(1,378)		(4,803)
Fair Value, Measurements, Nonrecurring | Consumer
Fair Value, Assets Measured on a Nonrecurring Basis
Increase (decrease) in value of assets	(1)		(112)		(264)

[1] Covered OREO results from the WFIB and UCB FDIC-assisted acquisitions for which the Company entered into shared-loss agreements with the FDIC whereby the FDIC will reimburse the Company for 80% of eligible losses. As such, the Company's liability for losses is 20% of the $1.0 million in losses, or $205 thousand, and 20% of the $3.4 million in losses, or $675 thousand, and 20% of the $11.2 million in losses, or $2.2 million for the years ended December 31, 2014, 2013, and 2012, respectively.