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Loans and Allowance for Loan Losses (Details 4) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Impaired loans
Impaired loans, Related Allowance	$ 13,200,000		$ 13,200,000		$ 18,996,000
Impaired Loans, second quarter average recorded principal balance	57,561,000	50,229,000
Impaired loans, Unpaid Contractual Principal Balance	71,358,000		71,358,000		97,771,000
Impaired loans, Recorded Principal Balance	51,623,000		51,623,000		70,978,000
Impaired loans, Year-To-Date Average Recorded Principal Balance			62,033,000	55,471,000
Total commercial [Member]
Impaired loans
Impaired loans, Related Allowance	12,584,000		12,584,000		18,645,000
Impaired Loans, second quarter average recorded principal balance	55,400,000	47,456,000
Impaired loans, Unpaid Contractual Principal Balance	68,419,000		68,419,000		94,668,000
Impaired loans, Recorded Principal Balance	49,478,000		49,478,000		68,893,000
Impaired loans, Year-To-Date Average Recorded Principal Balance			59,897,000	52,587,000
Total retail [Member]
Impaired loans
Impaired loans, Related Allowance	616,000		616,000		351,000
Impaired Loans, second quarter average recorded principal balance	2,161,000	2,773,000
Impaired loans, Unpaid Contractual Principal Balance	2,939,000		2,939,000		3,103,000
Impaired loans, Recorded Principal Balance	2,145,000		2,145,000		2,085,000
Impaired loans, Year-To-Date Average Recorded Principal Balance			2,136,000	2,884,000
Impaired loans with no related allowance [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	29,211,000		29,211,000		33,129,000
Recorded Principal Balance, with no related allowance	17,123,000		17,123,000		20,839,000
Average Recorded Principal Balance, with no related allowance	18,164,000	20,813,000	19,055,000	25,289,000
Impaired loans with no related allowance [Member] | Commercial and industrial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	3,896,000		3,896,000		4,670,000
Recorded Principal Balance, with no related allowance	3,129,000		3,129,000		4,254,000
Average Recorded Principal Balance, with no related allowance	3,270,000	1,871,000	3,598,000	1,959,000
Impaired loans with no related allowance [Member] | Vacant land, land development and residential construction [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	2,898,000		2,898,000		5,308,000
Recorded Principal Balance, with no related allowance	1,794,000		1,794,000		2,755,000
Average Recorded Principal Balance, with no related allowance	1,958,000	1,587,000	2,224,000	4,415,000
Impaired loans with no related allowance [Member] | Real Estate - Owner Occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	5,100,000		5,100,000		5,525,000
Recorded Principal Balance, with no related allowance	3,535,000		3,535,000		3,572,000
Average Recorded Principal Balance, with no related allowance	3,661,000	4,187,000	3,631,000	4,432,000
Impaired loans with no related allowance [Member] | Real Estate - Non-Owner Occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	11,639,000		11,639,000		14,017,000
Recorded Principal Balance, with no related allowance	6,685,000		6,685,000		8,131,000
Average Recorded Principal Balance, with no related allowance	7,145,000	10,453,000	7,473,000	12,227,000
Impaired loans with no related allowance [Member] | Real Estate - Multi-Family and Residential Rental [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	4,027,000		4,027,000		1,309,000
Recorded Principal Balance, with no related allowance	852,000		852,000		671,000
Average Recorded Principal Balance, with no related allowance	855,000	1,520,000	794,000	1,364,000
Impaired loans with no related allowance [Member] | Total commercial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	27,560,000		27,560,000		30,829,000
Recorded Principal Balance, with no related allowance	15,995,000		15,995,000		19,383,000
Average Recorded Principal Balance, with no related allowance	16,889,000	19,618,000	17,720,000	24,397,000
Impaired loans with no related allowance [Member] | Retail Home Equity and Other [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	500,000		500,000		1,000,000
Recorded Principal Balance, with no related allowance	477,000		477,000		727,000
Average Recorded Principal Balance, with no related allowance	600,000	768,000	642,000	562,000
Impaired loans with no related allowance [Member] | Retail 1-4 Family Mortgages [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	1,151,000		1,151,000		1,300,000
Recorded Principal Balance, with no related allowance	651,000		651,000		729,000
Average Recorded Principal Balance, with no related allowance	675,000	427,000	693,000	330,000
Impaired loans with no related allowance [Member] | Total retail [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	1,651,000		1,651,000		2,300,000
Recorded Principal Balance, with no related allowance	1,128,000		1,128,000		1,456,000
Average Recorded Principal Balance, with no related allowance	1,275,000	1,195,000	1,335,000	892,000
Impaired loans with an allowance [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	42,147,000		42,147,000		64,642,000
Recorded Principal Balance, with related allowance	34,500,000		34,500,000		50,139,000
Impaired loans, Related Allowance	13,200,000		13,200,000		18,996,000
Impaired Loans, second quarter average recorded principal balance	39,397,000	29,416,000	42,978,000	30,182,000
Impaired loans with an allowance [Member] | Commercial and industrial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	4,871,000		4,871,000		3,500,000
Recorded Principal Balance, with related allowance	4,272,000		4,272,000		3,023,000
Impaired loans, Related Allowance	1,680,000		1,680,000		1,172,000
Impaired Loans, second quarter average recorded principal balance	3,909,000	3,913,000	3,613,000	4,916,000
Impaired loans with an allowance [Member] | Vacant land, land development and residential construction [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	3,185,000		3,185,000		5,551,000
Recorded Principal Balance, with related allowance	2,844,000		2,844,000		4,267,000
Impaired loans, Related Allowance	1,416,000		1,416,000		1,799,000
Impaired Loans, second quarter average recorded principal balance	3,366,000	6,812,000	3,667,000	5,998,000
Impaired loans with an allowance [Member] | Real Estate - Owner Occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	5,699,000		5,699,000		8,544,000
Recorded Principal Balance, with related allowance	5,427,000		5,427,000		7,039,000
Impaired loans, Related Allowance	2,343,000		2,343,000		2,180,000
Impaired Loans, second quarter average recorded principal balance	5,545,000	4,330,000	6,043,000	4,972,000
Impaired loans with an allowance [Member] | Real Estate - Non-Owner Occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	21,331,000		21,331,000		32,331,000
Recorded Principal Balance, with related allowance	15,919,000		15,919,000		22,009,000
Impaired loans, Related Allowance	5,907,000		5,907,000		7,319,000
Impaired Loans, second quarter average recorded principal balance	17,904,000	9,757,000	19,272,000	9,129,000
Impaired loans with an allowance [Member] | Real Estate - Multi-Family and Residential Rental [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	5,773,000		5,773,000		13,913,000
Recorded Principal Balance, with related allowance	5,021,000		5,021,000		13,172,000
Impaired loans, Related Allowance	1,238,000		1,238,000		6,175,000
Impaired Loans, second quarter average recorded principal balance	7,787,000	3,026,000	9,582,000	3,175,000
Impaired loans with an allowance [Member] | Total commercial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	40,859,000		40,859,000		63,839,000
Recorded Principal Balance, with related allowance	33,483,000		33,483,000		49,510,000
Impaired loans, Related Allowance	12,584,000		12,584,000		18,645,000
Impaired Loans, second quarter average recorded principal balance	38,511,000	27,838,000	42,177,000	28,190,000
Impaired loans with an allowance [Member] | Retail Home Equity and Other [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	438,000		438,000		286,000
Recorded Principal Balance, with related allowance	375,000		375,000		229,000
Impaired loans, Related Allowance	362,000		362,000		215,000
Impaired Loans, second quarter average recorded principal balance	300,000	1,005,000	277,000	1,307,000
Impaired loans with an allowance [Member] | Retail 1-4 Family Mortgages [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	850,000		850,000		517,000
Recorded Principal Balance, with related allowance	642,000		642,000		400,000
Impaired loans, Related Allowance	254,000		254,000		136,000
Impaired Loans, second quarter average recorded principal balance	586,000	573,000	524,000	685,000
Impaired loans with an allowance [Member] | Total retail [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	1,288,000		1,288,000		803,000
Recorded Principal Balance, with related allowance	1,017,000		1,017,000		629,000
Impaired loans, Related Allowance	616,000		616,000		351,000
Impaired Loans, second quarter average recorded principal balance	$ 886,000	$ 1,578,000	$ 801,000	$ 1,992,000

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