OTHER ASSETS (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
OTHER ASSETS
Capitalized mortgage servicing rights	$ 3,198,000	$ 3,067,000	$ 2,035,000
Accrued interest receivable	14,731,000	11,350,000
Investment in tax credits	8,159,000	9,527,000
FDIC insurance	5,872,000	7,095,000
Accrued federal and state tax receivable	13,665,000	1,480,000
Derivative assets	19,668,000	13,926,000
Other	10,012,000	5,173,000
Total other assets	75,305,000	51,618,000
Other assets
Mortgage loans sold and serviced for others	603,700,000	486,600,000	319,800,000
Servicing fees	2,800,000	1,200,000	2,000,000
Significant assumptions used in the valuation of servicing rights
Weighted average discount rate (as a percent)		11.14%
Mortgage servicing rights activity
Balance at beginning of year	3,067,000	2,035,000
Additions	1,482,000	1,555,000
Amortization	(755,000)	(523,000)
Impairment Adjustment	(596,000)
Balance at end of year	$ 3,198,000	$ 3,067,000	$ 2,035,000
Minimum
Significant assumptions used in the valuation of servicing rights
Pre-payment speed (as a percent)		13.25%
Maximum
Significant assumptions used in the valuation of servicing rights
Pre-payment speed (as a percent)		26.02%