GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Changes in the carrying amount of goodwill
Balance, at the beginning of the period	$ 39,141,000	$ 47,301,000
Adjustments to Los Padres goodwill, including resolution of matter with FDIC regarding settlement accounting for wholly-owned subsidiary of Los Padres		(8,160,000)
Balance, at the end of the period	79,866,000	39,141,000	47,301,000
Finite lived intangible assets
Remaining weighted average amortization period	2 years 4 months 24 days
Estimated aggregate amortization expense related to the intangible assets
2013	4,500,000
2014	3,800,000
2015	3,500,000
2016	1,800,000
2017	587,000
Gross amount of CDI and CRI:
Balance, beginning of year	67,100,000	76,319,000	75,911,000
Addition due to acquisition	4,924,000		2,189,000
Fully amortized portion	(20,746,000)	(9,219,000)	(1,781,000)
Removal due to branch sale	(5,866,000)
Balance, end of year	45,412,000	67,100,000	76,319,000
Accumulated Amortization:
Balance, beginning of year	(49,685,000)	(50,476,000)	(42,615,000)
Amortization	(6,326,000)	(8,428,000)	(9,642,000)
Fully amortized portion	20,746,000	9,219,000	1,781,000
Removal due to branch sale	4,576,000
Balance, end of year	(30,689,000)	(49,685,000)	(50,476,000)
Finite lived intangible assets, net
Net CDI and CRI, end of year	14,723,000	17,415,000	25,843,000
Additional information
Amount of CDI written off related to previously acquired deposits that were sold in connection with the sale of branches	1,300,000
Los Padres Bank
Changes in the carrying amount of goodwill
Tax deductible addition from acquisition			47,301,000
EQF
Changes in the carrying amount of goodwill
Tax deductible addition from acquisition	19,033,000
Celtic
Changes in the carrying amount of goodwill
Non-tax deductible addition from acquisition	6,645,000
APB
Changes in the carrying amount of goodwill
Non-tax deductible addition from acquisition	$ 15,047,000