Allowance for Loan Losses Troubled Debt Restructuring on Financing Receivables (Details) (USD $) In Thousands, unless otherwise specified																																																																																																																								9 Months Ended						3 Months Ended		9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Sep. 30, 2013 C&I		Dec. 31, 2012 C&I		Sep. 30, 2012 C&I		Sep. 30, 2013 Commercial Real Estate		Dec. 31, 2012 Commercial Real Estate		Sep. 30, 2012 Commercial Real Estate		Sep. 30, 2013 Construction		Dec. 31, 2012 Construction		Sep. 30, 2012 Construction		Sep. 30, 2013 Total commercial		Dec. 31, 2012 Total commercial		Sep. 30, 2012 Total commercial		Sep. 30, 2013 Installment		Dec. 31, 2012 Installment		Sep. 30, 2012 Installment		Sep. 30, 2013 Home Equity Line of Credit		Dec. 31, 2012 Home Equity Line of Credit		Sep. 30, 2012 Home Equity Line of Credit		Sep. 30, 2013 Consumer Credit Card Financing Receivable		Dec. 31, 2012 Consumer Credit Card Financing Receivable		Sep. 30, 2012 Consumer Credit Card Financing Receivable	Sep. 30, 2013 Residential mortgages		Dec. 31, 2012 Residential mortgages		Sep. 30, 2012 Residential mortgages		Sep. 30, 2013 Total consumer		Dec. 31, 2012 Total consumer		Sep. 30, 2012 Total consumer		Sep. 30, 2013 Originated Loans Commercial C&I		Dec. 31, 2012 Originated Loans Commercial C&I		Sep. 30, 2012 Originated Loans Commercial C&I		Sep. 30, 2013 Originated Loans Commercial Commercial Real Estate		Dec. 31, 2012 Originated Loans Commercial Commercial Real Estate		Sep. 30, 2012 Originated Loans Commercial Commercial Real Estate		Sep. 30, 2013 Originated Loans Commercial Construction		Dec. 31, 2012 Originated Loans Commercial Construction		Sep. 30, 2012 Originated Loans Commercial Construction		Sep. 30, 2013 Originated Loans Commercial Total commercial		Dec. 31, 2012 Originated Loans Commercial Total commercial		Sep. 30, 2012 Originated Loans Commercial Total commercial		Sep. 30, 2013 Originated Consumer Loans Installment		Dec. 31, 2012 Originated Consumer Loans Installment		Sep. 30, 2012 Originated Consumer Loans Installment		Sep. 30, 2013 Originated Consumer Loans Home Equity Line of Credit		Dec. 31, 2012 Originated Consumer Loans Home Equity Line of Credit		Sep. 30, 2012 Originated Consumer Loans Home Equity Line of Credit		Sep. 30, 2013 Originated Consumer Loans Consumer Credit Card Financing Receivable		Dec. 31, 2012 Originated Consumer Loans Consumer Credit Card Financing Receivable		Sep. 30, 2012 Originated Consumer Loans Consumer Credit Card Financing Receivable		Sep. 30, 2013 Originated Consumer Loans Residential mortgages		Dec. 31, 2012 Originated Consumer Loans Residential mortgages		Sep. 30, 2012 Originated Consumer Loans Residential mortgages		Sep. 30, 2013 Originated Consumer Loans Total consumer		Dec. 31, 2012 Originated Consumer Loans Total consumer		Sep. 30, 2012 Originated Consumer Loans Total consumer		Sep. 30, 2013 Originated Loans		Dec. 31, 2012 Originated Loans		Sep. 30, 2012 Originated Loans		Sep. 30, 2013 Acquired Loans		Sep. 30, 2013 Acquired Loans C&I	Sep. 30, 2013 Acquired Loans Total commercial	Sep. 30, 2012 Acquired Loans Total commercial	Sep. 30, 2013 Acquired Loans Home Equity Line of Credit		Sep. 30, 2013 Acquired Loans Total consumer		Sep. 30, 2013 Covered Loans	Sep. 30, 2012 Covered Loans	Sep. 30, 2013 Covered Loans	Sep. 30, 2012 Covered Loans	Sep. 30, 2013 Covered Loans Commercial C&I		Dec. 31, 2012 Covered Loans Commercial C&I		Sep. 30, 2012 Covered Loans Commercial C&I		Sep. 30, 2013 Covered Loans Commercial Commercial Real Estate		Dec. 31, 2012 Covered Loans Commercial Commercial Real Estate		Sep. 30, 2012 Covered Loans Commercial Commercial Real Estate		Sep. 30, 2013 Covered Loans Commercial Construction		Dec. 31, 2012 Covered Loans Commercial Construction		Sep. 30, 2012 Covered Loans Commercial Construction		Sep. 30, 2013 Covered Loans Commercial Total commercial		Dec. 31, 2012 Covered Loans Commercial Total commercial		Sep. 30, 2012 Covered Loans Commercial Total commercial		Sep. 30, 2013 Covered Loans Commercial Total consumer		Sep. 30, 2013 Covered Consumer Loans Home Equity Line of Credit		Dec. 31, 2012 Covered Consumer Loans Home Equity Line of Credit		Sep. 30, 2013 Covered Consumer Loans Residential mortgages		Sep. 30, 2012 Covered Consumer Loans Total consumer	Sep. 30, 2013 Covered TDR Loans		Dec. 31, 2012 Covered TDR Loans		Sep. 30, 2012 Covered TDR Loans		Sep. 30, 2012 Covered TDR Loans Total commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 136,505	$ 150,487	$ 166,327	$ 6,998	[1]	$ 4,380	[1]	$ 7,691	[1]	$ 58,532	[1]	$ 66,577	[1]	$ 69,843	[1]	$ 4,998	[1]	$ 11,126	[1]	$ 18,216	[1]	$ 70,528	[1]	$ 82,083	[1]	$ 95,750	[1]	$ 28,578	[1]	$ 30,870	[1]	$ 32,577	[1]	$ 12,929	[1]	$ 11,913	[1]	$ 11,664	[1]	$ 1,253	[1]	$ 1,612	[1]	$ 1,767	$ 23,217	[1]	$ 24,009	[1]	$ 24,569	[1]	$ 65,977	[1]	$ 68,404	[1]	$ 70,577	[1]	$ 5,455	[1]	$ 2,617	[1]	$ 2,413	[1]	$ 15,508	[1]	$ 16,305	[1]	$ 17,763	[1]	$ 958	[1]	$ 2,955	[1]	$ 3,577	[1]	$ 21,921	[1]	$ 21,877	[1]	$ 23,753	[1]	$ 28,578	[1]	$ 30,870	[1]	$ 32,577	[1]	$ 6,916	[1]	$ 6,281	[1]	$ 6,922	[1]	$ 1,253	[1]	$ 1,612	[1]	$ 1,767	[1]	$ 23,065	[1]	$ 24,009	[1]	$ 24,569	[1]	$ 59,812	[1]	$ 62,772	[1]	$ 65,835	[1]	$ 81,733	[1]	$ 84,649	[1]	$ 89,588	[1]	$ 266	[1]	$ 6	$ 6		$ 260	[1]	$ 260	[1]					$ 1,537	[1]	$ 1,763	[1]	$ 5,278	[1]	$ 43,024	[1]	$ 50,272	[1]	$ 52,079	[1]	$ 4,040	[1]	$ 8,171	[1]	$ 14,640	[1]	$ 48,601	[1]	$ 60,206	[1]	$ 71,997	[1]	$ 5,905	[1]	$ 5,753	[1]	$ 5,632	[1]	$ 152	[1]	$ 4,742	$ 54,506	[1]	$ 65,838	[1]	$ 76,739	[1]	$ 71,997
Financing Receiables, Modifications, Unpaid Principal Balance	185,435	202,273	215,236	11,916	[1]	10,042	[1]	14,694	[1]	78,100	[1]	78,184	[1]	78,988	[1]	25,033	[1]	40,966	[1]	46,592	[1]	115,049	[1]	129,192	[1]	140,274	[1]	29,960	[1]	32,653	[1]	34,414	[1]	13,339	[1]	12,154	[1]	11,976	[1]	1,253	[1]	1,612	[1]	1,767	25,834	[1]	26,662	[1]	26,805	[1]	70,386	[1]	73,081	[1]	74,962	[1]	9,533	[1]	8,044	[1]	8,478	[1]	19,848	[1]	20,701	[1]	21,307	[1]	1,237	[1]	3,419	[1]	4,025	[1]	30,618	[1]	32,164	[1]	33,810	[1]	29,960	[1]	32,653	[1]	34,414	[1]	7,255	[1]	6,488	[1]	7,202	[1]	1,253	[1]	1,612	[1]	1,767	[1]	25,683	[1]	26,662	[1]	26,805	[1]	64,151	[1]	67,415	[1]	70,188	[1]	94,769	[1]	99,579	[1]	103,998	[1]	313	[1]	6			307	[1]	307	[1]					2,377	[1]	1,998	[1]	6,216	[1]	58,252	[1]	57,483	[1]	57,681	[1]	23,796	[1]	37,547	[1]	42,567	[1]	84,425	[1]	97,028	[1]	106,464	[1]	5,928	[1]	5,777	[1]	5,666	[1]	151	[1]	4,774	90,353	[1]	102,694	[1]	111,238	[1]
Provision for Loan Losses Before Benefit Attributable to FDIC Loss Share Agreements																																																																																																																								$ 0	$ 6					$ 2,855	$ 7,698	$ 19,009	$ 28,177
financing receivables, modifications, number of contracts at period end	2,732	2,842	2,964	40		27		33		73		60		61		41		38		37		154		125		131		1,655		1,769		1,840		291		261		259		339		389		426	293		298		308		2,578		2,717		2,833		35		24		22		49		40		36		31		28		27		115		92		85		1,655		1,769		1,840		240		226		229		339		389		426		292		298		308		2,526		2,682		2,803		2,641		2,774		2,888		4		1			3		3						4		3		11		24		20		25		10		10		10		38		33		46		49		48		35		1		30	87		68		76

[1] Note 1: The differences between the recorded investment and unpaid principal balance amounts represents partial charge offs.