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Loans and Allowance for Loan Losses (Details 4) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Impaired loans
Impaired loans, Related Allowance	$ 15,802,000		$ 15,802,000		$ 18,996,000
Impaired loans, Unpaid Contractual Principal Balance	78,570,000		78,570,000		97,771,000
Impaired loans, Recorded Principal Balance	63,214,000		63,214,000		70,978,000
Impaired loans, Year-To-Date Average Recorded Principal Balance			62,328,000	58,180,000
Impaired Loans, Third Quarter Average Recorded Principal Balance	57,418,000	46,191,000
Total commercial [Member]
Impaired loans
Impaired loans, Related Allowance	15,497,000		15,497,000		18,645,000
Impaired loans, Unpaid Contractual Principal Balance	75,831,000		75,831,000		94,668,000
Impaired loans, Recorded Principal Balance	61,378,000		61,378,000		68,893,000
Impaired loans, Year-To-Date Average Recorded Principal Balance			60,267,000	55,203,000
Impaired Loans, Third Quarter Average Recorded Principal Balance	55,427,000	43,441,000
Total retail [Member]
Impaired loans
Impaired loans, Related Allowance	305,000		305,000		351,000
Impaired loans, Unpaid Contractual Principal Balance	2,739,000		2,739,000		3,103,000
Impaired loans, Recorded Principal Balance	1,836,000		1,836,000		2,085,000
Impaired loans, Year-To-Date Average Recorded Principal Balance			2,061,000	2,977,000
Impaired Loans, Third Quarter Average Recorded Principal Balance	1,991,000	2,750,000
Impaired loans with no related allowance [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	22,752,000		22,752,000		33,129,000
Recorded Principal Balance, with no related allowance	14,931,000		14,931,000		20,839,000
Average Recorded Principal Balance, with no related allowance	16,027,000	19,786,000	18,024,000	26,340,000
Impaired loans with no related allowance [Member] | Commercial and industrial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	4,210,000		4,210,000		4,670,000
Recorded Principal Balance, with no related allowance	3,289,000		3,289,000		4,254,000
Average Recorded Principal Balance, with no related allowance	3,209,000	1,353,000	3,521,000	1,704,000
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	2,279,000		2,279,000		5,308,000
Recorded Principal Balance, with no related allowance	1,166,000		1,166,000		2,755,000
Average Recorded Principal Balance, with no related allowance	1,480,000	2,278,000	1,959,000	6,387,000
Impaired loans with no related allowance [Member] | Real estate - owner occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	4,578,000		4,578,000		5,525,000
Recorded Principal Balance, with no related allowance	3,246,000		3,246,000		3,572,000
Average Recorded Principal Balance, with no related allowance	3,391,000	4,071,000	3,535,000	4,233,000
Impaired loans with no related allowance [Member] | Real estate - non-owner occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	7,493,000		7,493,000		14,017,000
Recorded Principal Balance, with no related allowance	4,979,000		4,979,000		8,131,000
Average Recorded Principal Balance, with no related allowance	5,832,000	9,286,000	6,850,000	12,306,000
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	2,172,000		2,172,000		1,309,000
Recorded Principal Balance, with no related allowance	985,000		985,000		671,000
Average Recorded Principal Balance, with no related allowance	918,000	1,579,000	841,000	979,000
Impaired loans with no related allowance [Member] | Total commercial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	20,732,000		20,732,000		30,829,000
Recorded Principal Balance, with no related allowance	13,665,000		13,665,000		19,383,000
Average Recorded Principal Balance, with no related allowance	14,830,000	18,567,000	16,706,000	25,609,000
Impaired loans with no related allowance [Member] | Retail home equity and other [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	580,000		580,000		1,000,000
Recorded Principal Balance, with no related allowance	487,000		487,000		727,000
Average Recorded Principal Balance, with no related allowance	482,000	856,000	603,000	503,000
Impaired loans with no related allowance [Member] | Retail 1-4 family mortgages [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	1,440,000		1,440,000		1,300,000
Recorded Principal Balance, with no related allowance	779,000		779,000		729,000
Average Recorded Principal Balance, with no related allowance	715,000	363,000	715,000	228,000
Impaired loans with no related allowance [Member] | Total retail [Member]
Impaired loans
Unpaid Contractual Principal Balance, with no related allowance	2,020,000		2,020,000		2,300,000
Recorded Principal Balance, with no related allowance	1,266,000		1,266,000		1,456,000
Average Recorded Principal Balance, with no related allowance	1,197,000	1,219,000	1,318,000	731,000
Impaired loans with an allowance [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	55,818,000		55,818,000		64,642,000
Recorded Principal Balance, with related allowance	48,283,000		48,283,000		50,139,000
Impaired loans, Related Allowance	15,802,000		15,802,000		18,996,000
Impaired Loans, Average Recorded Principal Balance	41,391,000	26,405,000	44,304,000	31,840,000
Impaired loans with an allowance [Member] | Commercial and industrial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	3,278,000		3,278,000		3,500,000
Recorded Principal Balance, with related allowance	2,785,000		2,785,000		3,023,000
Impaired loans, Related Allowance	1,358,000		1,358,000		1,172,000
Impaired Loans, Average Recorded Principal Balance	3,528,000	4,886,000	3,406,000	6,422,000
Impaired loans with an allowance [Member] | Vacant land, land development, and residential construction [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	3,305,000		3,305,000		5,551,000
Recorded Principal Balance, with related allowance	3,117,000		3,117,000		4,267,000
Impaired loans, Related Allowance	1,465,000		1,465,000		1,799,000
Impaired Loans, Average Recorded Principal Balance	2,981,000	2,064,000	3,529,000	3,814,000
Impaired loans with an allowance [Member] | Real estate - owner occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	3,233,000		3,233,000		8,544,000
Recorded Principal Balance, with related allowance	2,813,000		2,813,000		7,039,000
Impaired loans, Related Allowance	1,326,000		1,326,000		2,180,000
Impaired Loans, Average Recorded Principal Balance	4,120,000	4,205,000	5,235,000	5,821,000
Impaired loans with an allowance [Member] | Real estate - non-owner occupied [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	40,590,000		40,590,000		32,331,000
Recorded Principal Balance, with related allowance	34,521,000		34,521,000		22,009,000
Impaired loans, Related Allowance	10,061,000		10,061,000		7,319,000
Impaired Loans, Average Recorded Principal Balance	25,220,000	11,291,000	23,085,000	10,650,000
Impaired loans with an allowance [Member] | Real estate - multi-family and residential rental [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	4,693,000		4,693,000		13,913,000
Recorded Principal Balance, with related allowance	4,477,000		4,477,000		13,172,000
Impaired loans, Related Allowance	1,287,000		1,287,000		6,175,000
Impaired Loans, Average Recorded Principal Balance	4,748,000	2,428,000	8,306,000	2,887,000
Impaired loans with an allowance [Member] | Total commercial [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	55,099,000		55,099,000		63,839,000
Recorded Principal Balance, with related allowance	47,713,000		47,713,000		49,510,000
Impaired loans, Related Allowance	15,497,000		15,497,000		18,645,000
Impaired Loans, Average Recorded Principal Balance	40,597,000	24,874,000	43,561,000	29,594,000
Impaired loans with an allowance [Member] | Retail home equity and other [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	235,000		235,000		286,000
Recorded Principal Balance, with related allowance	206,000		206,000		229,000
Impaired loans, Related Allowance	206,000		206,000		215,000
Impaired Loans, Average Recorded Principal Balance	291,000	753,000	259,000	1,314,000
Impaired loans with an allowance [Member] | Retail 1-4 family mortgages [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	484,000		484,000		517,000
Recorded Principal Balance, with related allowance	364,000		364,000		400,000
Impaired loans, Related Allowance	99,000		99,000		136,000
Impaired Loans, Average Recorded Principal Balance	503,000	778,000	484,000	932,000
Impaired loans with an allowance [Member] | Total retail [Member]
Impaired loans
Unpaid Contractual Principal Balance, with related allowance	719,000		719,000		803,000
Recorded Principal Balance, with related allowance	570,000		570,000		629,000
Impaired loans, Related Allowance	305,000		305,000		351,000
Impaired Loans, Average Recorded Principal Balance	$ 794,000	$ 1,531,000	$ 743,000	$ 2,246,000

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