Loans and Allowances for Credit Losses Part 5 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	$ 2,564	$ 1,050	$ 7,392	$ 2,124
Troubled Debt Restructuring, Recorded Investment	72,571	84,938	72,571	84,938	83,197
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	36,395	32,362	36,395	32,362	22,836
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	36,176	52,576	36,176	52,576	60,361
Troubled Debt Restructuring, Specific allowance	291	2,103	291	2,103	2,760
Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	121	83	201
Troubled Debt Restructuring, Recorded Investment	27,992	30,474	27,992	30,474	32,891
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	9,909	13,646	9,909	13,646	13,298
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	18,083	16,828	18,083	16,828	19,593
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	2,564	929	7,309	1,923
Troubled Debt Restructuring, Recorded Investment	44,579	54,464	44,579	54,464	50,306
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	26,486	18,716	26,486	18,716	9,538
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	18,093	35,748	18,093	35,748	40,768
Troubled Debt Restructuring, Specific allowance	291	2,103	291	2,103	2,760
Commercial Loan [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	301
Troubled Debt Restructuring, Recorded Investment	4,901	6,579	4,901	6,579	6,228
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	3,566	3,654	3,566	3,654	2,868
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	1,335	2,925	1,335	2,925	3,360
Troubled Debt Restructuring, Specific allowance	18	26	18	26	24
Commercial Loan [Member] | Energy [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Loan [Member] | Services [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	301
Troubled Debt Restructuring, Recorded Investment	2,594	3,747	2,594	3,747	3,529
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	2,109	2,010	2,109	2,010	1,907
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	485	1,737	485	1,737	1,622
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Loan [Member] | Wholesale/retail [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	1,557	1,804	1,557	1,804	1,739
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,385	1,579	1,385	1,579	961
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	172	225	172	225	778
Troubled Debt Restructuring, Specific allowance	18	26	18	26	24
Commercial Loan [Member] | Manufacturing [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Loan [Member] | Healthcare [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	72	65	72	65	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	72	65	72	65	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Loan [Member] | Integrated food services [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Loan [Member] | Other commercial and industrial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	678	963	678	963	960
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	678	963	678	963	960
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Real Estate [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	1,219	929	5,940	1,568
Troubled Debt Restructuring, Recorded Investment	30,540	41,646	30,540	41,646	37,627
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	18,232	8,849	18,232	8,849	5,106
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	12,308	32,797	12,308	32,797	32,521
Troubled Debt Restructuring, Specific allowance	131	1,795	131	1,795	2,454
Commercial Real Estate [Member] | Construction and land development [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	982	427	3,252	1,066
Troubled Debt Restructuring, Recorded Investment	18,406	28,902	18,406	28,902	25,890
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	9,842	5,111	9,842	5,111	3,585
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	8,564	23,791	8,564	23,791	22,305
Troubled Debt Restructuring, Specific allowance	76	1,069	76	1,069	1,577
Commercial Real Estate [Member] | Retail [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	150	502	150	502
Troubled Debt Restructuring, Recorded Investment	3,448	1,450	3,448	1,450	1,070
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	3,448	0	3,448	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	1,450	0	1,450	1,070
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Real Estate [Member] | Office [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	269	0
Troubled Debt Restructuring, Recorded Investment	3,376	3,085	3,376	3,085	2,496
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,368	1,421	1,368	1,421	1,134
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	2,008	1,664	2,008	1,664	1,362
Troubled Debt Restructuring, Specific allowance	0	0	0	0	215
Commercial Real Estate [Member] | Multifamily [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Real Estate [Member] | Industrial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Commercial Real Estate [Member] | Other commercial real estate [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	87	0	2,269	0
Troubled Debt Restructuring, Recorded Investment	5,310	8,209	5,310	8,209	8,171
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	3,574	2,317	3,574	2,317	387
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	1,736	5,892	1,736	5,892	7,784
Troubled Debt Restructuring, Specific allowance	55	726	55	726	662
Residential Mortgage [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	121	83	201
Troubled Debt Restructuring, Recorded Investment	27,992	30,474	27,992	30,474	32,891
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	9,909	13,646	9,909	13,646	13,298
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	18,083	16,828	18,083	16,828	19,593
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Residential Mortgage [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	24	54
Troubled Debt Restructuring, Recorded Investment	6,925	6,201	6,925	6,201	6,283
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	4,245	6,201	4,245	6,201	1,396
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	2,680	0	2,680	0	4,887
Troubled Debt Restructuring, Specific allowance	54	282	54	282	282
Residential Mortgage [Member] | Permanent mortgage [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	121	83	201
Troubled Debt Restructuring, Recorded Investment	3,402	3,804	3,402	3,804	3,917
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	2,225	2,773	2,225	2,773	2,445
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	1,177	1,031	1,177	1,031	1,472
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Residential Mortgage [Member] | Permanent mortgage [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	24	54
Troubled Debt Restructuring, Recorded Investment	6,925	6,201	6,925	6,201	6,283
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	4,245	6,201	4,245	6,201	1,396
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	2,680	0	2,680	0	4,887
Troubled Debt Restructuring, Specific allowance	54	282	54	282	282
Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	24,590	26,670	24,590	26,670	28,974
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	7,684	10,873	7,684	10,873	10,853
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	16,906	15,797	16,906	15,797	18,121
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Residential Mortgage [Member] | Home equity [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Consumer Loan [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	1,345	0	1,345	0
Troubled Debt Restructuring, Recorded Investment	2,213	38	2,213	38	168
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	443	12	443	12	168
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	1,770	26	1,770	26	0
Troubled Debt Restructuring, Specific allowance	88	0	88	0	0
Consumer Loan [Member] | Indirect automobile [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Troubled Debt Restructuring, Recorded Investment	0	0	0	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	0	0	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Consumer Loan [Member] | Other consumer [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	1,345	0	1,345	0
Troubled Debt Restructuring, Recorded Investment	2,213	38	2,213	38	168
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	443	12	443	12	168
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	1,770	26	1,770	26	0
Troubled Debt Restructuring, Specific allowance	$ 88	$ 0	$ 88	$ 0	$ 0