Loans and Allowances for Credit Losses Part 5 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	$ 109,335	$ 72,571	$ 109,335	$ 72,571	$ 97,985
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	40,198	36,395	40,198	36,395	48,126
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	69,137	36,176	69,137	36,176	49,859
Troubled Debt Restructuring, Specific allowance	420	291	420	291	273
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	290	2,564	1,492	7,392
Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	59,236	44,579	59,236	44,579	59,470
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	28,223	26,486	28,223	26,486	39,371
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	31,013	18,093	31,013	18,093	20,099
Troubled Debt Restructuring, Specific allowance	420	291	420	291	273
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	290	2,564	1,492	7,309
Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	50,099	27,992	50,099	27,992	38,515
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	11,975	9,909	11,975	9,909	8,755
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	38,124	18,083	38,124	18,083	29,760
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	83
Commercial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	5,234	4,901	5,234	4,901	5,521
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,445	3,566	1,445	3,566	3,525
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	3,789	1,335	3,789	1,335	1,996
Troubled Debt Restructuring, Specific allowance	259	18	259	18	60
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	154	0	154	0
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
Services [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	3,791	2,594	3,791	2,594	2,492
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,274	2,109	1,274	2,109	2,099
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	2,517	485	2,517	485	393
Troubled Debt Restructuring, Specific allowance	250	0	250	0	45
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Wholesale/retail [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	275	1,557	275	1,557	2,290
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	141	1,385	141	1,385	1,362
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	134	172	134	172	928
Troubled Debt Restructuring, Specific allowance	9	18	9	18	15
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Manufacturing [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	396	0	396	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	396	0	396	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	154	0	154	0
Healthcare [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	0	72	0	72	64
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	72	0	72	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
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
Other commercial and industrial [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	772	678	772	678	675
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	30	0	30	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	742	678	742	678	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	31,613	30,540	31,613	30,540	30,599
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	12,956	18,232	12,956	18,232	21,043
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	18,657	12,308	18,657	12,308	9,556
Troubled Debt Restructuring, Specific allowance	148	131	148	131	76
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	1,219	758	5,940
Construction and land development [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	10,673	18,406	10,673	18,406	14,898
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,776	9,842	1,776	9,842	9,989
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	8,897	8,564	8,897	8,564	4,909
Troubled Debt Restructuring, Specific allowance	148	76	148	76	76
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	982	54	3,252
Retail [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	6,030	3,448	6,030	3,448	6,785
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	2,032	3,448	2,032	3,448	5,735
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	3,998	0	3,998	0	1,050
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	150	627	150
Office [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	5,448	3,376	5,448	3,376	3,899
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,294	1,368	1,294	1,368	1,920
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	4,154	2,008	4,154	2,008	1,979
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	77	269
Multifamily [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	980	0	980	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	980	0	980	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
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
Other commercial real estate [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	8,482	5,310	8,482	5,310	5,017
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	6,874	3,574	6,874	3,574	3,399
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	1,608	1,736	1,608	1,736	1,618
Troubled Debt Restructuring, Specific allowance	0	55	0	55	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	87	0	2,269
Residential Mortgage [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	21,101	6,925	21,101	6,925	20,490
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	12,798	4,245	12,798	4,245	12,214
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	8,303	2,680	8,303	2,680	8,276
Troubled Debt Restructuring, Specific allowance	13	54	13	54	54
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	134	0	577	24
Permanent mortage [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	17,319	6,925	17,319	6,925	20,490
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	9,579	4,245	9,579	4,245	12,214
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	7,740	2,680	7,740	2,680	8,276
Troubled Debt Restructuring, Specific allowance	13	54	13	54	54
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	73	0	450	24
Permanent mortage [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	0	3,402	0	3,402	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	0	2,225	0	2,225	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	0	1,177	0	1,177	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	83
Permanent mortgages guaranteed by US govenment agencies [Member] | Accruing [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	50,099	24,590	50,099	24,590	38,515
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	11,975	7,684	11,975	7,684	8,755
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	38,124	16,906	38,124	16,906	29,760
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	0	0
Home equity {Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	3,782	0	3,782	0	0
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	3,219	0	3,219	0	0
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	563	0	563	0	0
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	61	0	127	0
Consumer [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	1,288	2,213	1,288	2,213	2,860
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	1,024	443	1,024	443	2,589
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	264	1,770	264	1,770	271
Troubled Debt Restructuring, Specific allowance	0	88	0	88	83
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	2	1,345	3	1,345
Indirect automobile [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	817	0	817	0	532
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	737	0	737	0	492
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	80	0	80	0	40
Troubled Debt Restructuring, Specific allowance	0	0	0	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	0	0	1	0
Other consumer [Member] | Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled Debt Restructuring, Recorded Investment	471	2,213	471	2,213	2,328
Troubled Debt Restructuring, Performing in Accordance With Modified Terms	287	443	287	443	2,097
Troubled Debt Restructuring, Not Performing in Accordance With Modified Terms	184	1,770	184	1,770	231
Troubled Debt Restructuring, Specific allowance	0	88	0	88	83
Financing Receivables, Impaired, Troubled Debt Restructuring, Charge-offs	$ 2	$ 1,345	$ 2	$ 1,345