Loans and Allowances for Credit Losses Part 5 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	$ 109,050	$ 74,929	$ 109,050	$ 74,929	$ 97,985
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	38,768	34,340	38,768	34,340	48,126
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	70,282	40,589	70,282	40,589	49,859
Troubled Debt Restructuring, Specific allowance	395	253	395	253	273
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	208	916	1,176	5,257
Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	48,733	28,415	48,733	28,415	38,515
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	12,598	11,347	12,598	11,347	8,755
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	36,135	17,068	36,135	17,068	29,760
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	32	0	112
Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	60,317	46,514	60,317	46,514	59,470
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	26,170	22,993	26,170	22,993	39,371
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	34,147	23,521	34,147	23,521	20,099
Troubled Debt Restructuring, Specific allowance	395	253	395	253	273
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	208	884	1,176	5,145
Commercial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	4,993	5,168	4,993	5,168	5,521
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,867	2,886	1,867	2,886	3,525
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	3,126	2,282	3,126	2,282	1,996
Troubled Debt Restructuring, Specific allowance	240	20	240	20	60
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Energy [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
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
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Services [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	3,065	2,700	3,065	2,700	2,492
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	710	1,381	710	1,381	2,099
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	2,355	1,319	2,355	1,319	393
Troubled Debt Restructuring, Specific allowance	228	0	228	0	45
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Wholesale/retail [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	1,107	1,612	1,107	1,612	2,290
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	968	1,428	968	1,428	1,362
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	139	184	139	184	928
Troubled Debt Restructuring, Specific allowance	12	20	12	20	15
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Manufacturing [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
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
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Healthcare [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	0	77	0	77	64
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	77	0	77	64
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
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Integrated food services [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
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
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial [Member] | Other commercial and industrial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	821	779	821	779	675
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	189	0	189	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	632	779	632	779	675
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial Real Estate [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	32,639	30,952	32,639	30,952	30,599
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	8,798	12,278	8,798	12,278	21,043
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	23,841	18,674	23,841	18,674	9,556
Troubled Debt Restructuring, Specific allowance	23	179	23	179	76
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	131	769	758	5,030
Commercial Real Estate [Member] | Construction and land development [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	11,734	18,217	11,734	18,217	14,898
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,934	4,238	1,934	4,238	9,989
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	9,800	13,979	9,800	13,979	4,909
Troubled Debt Restructuring, Specific allowance	23	76	23	76	76
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	54	769	54	2,579
Commercial Real Estate [Member] | Retail [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	5,681	3,618	5,681	3,618	6,785
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,604	3,618	1,604	3,618	5,735
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	4,077	0	4,077	0	1,050
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	627	0
Commercial Real Estate [Member] | Office [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	5,488	3,387	5,488	3,387	3,899
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,313	2,489	1,313	2,489	1,920
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	4,175	898	4,175	898	1,979
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	77	0	77	269
Commercial Real Estate [Member] | Multifamily [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	990	0	990	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	208	0	208	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	782	0	782	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial Real Estate [Member] | Industrial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
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
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Commercial Real Estate [Member] | Other commercial real estate [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	8,746	5,730	8,746	5,730	5,017
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	3,739	1,933	3,739	1,933	3,399
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	5,007	3,797	5,007	3,797	1,618
Troubled Debt Restructuring, Specific allowance	0	103	0	103	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	2,182
Residential Mortgage [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	48,733	28,415	48,733	28,415	38,515
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	12,598	11,347	12,598	11,347	8,755
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	36,135	17,068	36,135	17,068	29,760
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	32	0	112
Residential Mortgage [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	21,143	6,892	21,143	6,892	20,490
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	14,181	4,327	14,181	4,327	12,214
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	6,962	2,565	6,962	2,565	8,276
Troubled Debt Restructuring, Specific allowance	54	54	54	54	54
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	77	115	417	115
Residential Mortgage [Member] | Permanent mortgage [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	0	3,655	0	3,655	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	2,466	0	2,466	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	1,189	0	1,189	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	32	0	112
Residential Mortgage [Member] | Permanent mortgage [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	17,639	6,892	17,639	6,892	20,490
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	10,917	4,327	10,917	4,327	12,214
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	6,722	2,565	6,722	2,565	8,276
Troubled Debt Restructuring, Specific allowance	54	54	54	54	54
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	8	115	348	115
Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	48,733	24,760	48,733	24,760	38,515
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	12,598	8,881	12,598	8,881	8,755
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	36,135	15,879	36,135	15,879	29,760
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Residential Mortgage [Member] | Home equity [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	3,504	0	3,504	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	3,264	0	3,264	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	240	0	240	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	69	0	69	0
Consumer [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	1,542	3,502	1,542	3,502	2,860
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,324	3,502	1,324	3,502	2,589
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	218	0	218	0	271
Troubled Debt Restructuring, Specific allowance	78	0	78	0	83
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	1	0
Consumer [Member] | Indirect automobile [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	986	0	986	0	532
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	926	0	926	0	492
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	60	0	60	0	40
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	1	0
Consumer [Member] | Other consumer [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	556	3,502	556	3,502	2,328
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	398	3,502	398	3,502	2,097
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	158	0	158	0	231
Troubled Debt Restructuring, Specific allowance	78	0	78	0	83
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	$ 0	$ 0	$ 0	$ 0