Loans and Allowance for Loan Losses Loans and Allowance for Loan Losses (Number of Loans Moditifed in a TDR Table) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	2,842		2,502
Financing Receivable, Modifications, Recorded Investment	$ 150,487	[1]	$ 150,356	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	202,273	[1]	185,587	[1]
Noncovered Loans Commercial [Member] | Commercial and Industrial Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	24		14
Financing Receivable, Modifications, Recorded Investment	2,617	[1]	2,512	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	8,044	[1]	4,336	[1]
Noncovered Loans Commercial [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	40		28
Financing Receivable, Modifications, Recorded Investment	16,305	[1]	9,167	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	20,701	[1]	12,659	[1]
Noncovered Loans Commercial [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	28		22
Financing Receivable, Modifications, Recorded Investment	2,955	[1]	3,323	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	3,419	[1]	3,985	[1]
Noncovered Loans Commercial [Member] | Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	92		64
Financing Receivable, Modifications, Recorded Investment	21,877	[1]	15,002	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	32,164	[1]	20,980	[1]
Noncovered Consumer Loans [Member] | Consumer Installment Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	1,769		1,547
Financing Receivable, Modifications, Recorded Investment	30,870	[1]	33,571	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	32,653	[1]	33,723	[1]
Noncovered Consumer Loans [Member] | Home Equity Line of Credit [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	226		174
Financing Receivable, Modifications, Recorded Investment	6,281	[1]	4,763	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	6,488	[1]	4,763	[1]
Noncovered Consumer Loans [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	389		496
Financing Receivable, Modifications, Recorded Investment	1,612	[1]	2,202	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	1,612	[1]	2,202	[1]
Noncovered Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	298		177
Financing Receivable, Modifications, Recorded Investment	24,009	[1]	17,398	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	26,662	[1]	18,913	[1]
Noncovered Consumer Loans [Member] | Consumer Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	2,682		2,394
Financing Receivable, Modifications, Recorded Investment	62,772	[1]	57,934	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	67,415	[1]	59,601	[1]
Noncovered Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	2,774		2,458
Financing Receivable, Modifications, Recorded Investment	84,649	[1]	72,936	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	99,579	[1]	80,581	[1]
Covered Loans Commercial [Member] | Commercial and Industrial Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	3		15
Financing Receivable, Modifications, Recorded Investment	1,763	[1]	7,578	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	1,998	[1]	10,812	[1]
Covered Loans Commercial [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	20		21
Financing Receivable, Modifications, Recorded Investment	50,272	[1]	57,786	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	57,483	[1]	62,159	[1]
Covered Loans Commercial [Member] | Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	10		8
Financing Receivable, Modifications, Recorded Investment	8,171	[1]	12,056	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	37,547	[1]	32,035	[1]
Covered Loans Commercial [Member] | Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	33		44
Financing Receivable, Modifications, Recorded Investment	60,206	[1]	77,420	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	97,028	[1]	105,006	[1]
Covered Consumer Loans [Member] | Home Equity Line of Credit [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	35
Financing Receivable, Modifications, Recorded Investment	5,632	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	5,666	[1]
Covered TDR Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	68
Financing Receivable, Modifications, Recorded Investment	65,838	[1]	77,420
Financing Receiables, Modifications, Unpaid Principal Balance	$ 102,694	[1]

[1] (a) The differences between the recorded investment and unpaid principal balance amounts represents partial charge offs.