Allowance for Loan Losses Troubled Debt Restructuring on Financing Receivables (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Troubled Debt, Interest Income	$ 900,000		$ 800,000
Financing Receivable, Modifications, Recorded Investment	135,631,000		139,736,000		130,458,000
Financing Receiables, Modifications, Unpaid Principal Balance	178,117,000		188,598,000		173,976,000
financing receivables, modifications, number of contracts at period end	2,509		2,574		2,494
Commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	16,925,000	[1]	6,270,000	[1]	7,318,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	25,024,000	[1]	14,783,000	[1]	15,495,000	[1]
financing receivables, modifications, number of contracts at period end	56		45		51
Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	38,424,000	[1]	58,066,000	[1]	45,648,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	59,556,000	[1]	75,251,000	[1]	67,466,000	[1]
financing receivables, modifications, number of contracts at period end	91		83		94
Commercial Real Estate Construction Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	346,000	[1]	5,329,000	[1]	339,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	9,552,000	[1]	24,117,000	[1]	9,552,000	[1]
financing receivables, modifications, number of contracts at period end	40		42		40
Total commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	55,695,000	[1]	69,665,000	[1]	53,305,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	94,132,000	[1]	114,151,000	[1]	92,513,000	[1]
financing receivables, modifications, number of contracts at period end	187		170		185
Installment
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	28,077,000	[1]	26,615,000	[1]	25,880,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	28,809,000	[1]	27,739,000	[1]	26,662,000	[1]
financing receivables, modifications, number of contracts at period end	1,237		1,457		1,245
Home Equity Line of Credit
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	23,851,000	[1]	15,126,000	[1]	23,201,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	24,161,000	[1]	15,465,000	[1]	23,513,000	[1]
financing receivables, modifications, number of contracts at period end	508		336		483
Consumer Credit Card
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	815,000	[1]	1,034,000		854,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	815,000	[1]	1,034,000		854,000	[1]
financing receivables, modifications, number of contracts at period end	230		278		238
Residential Mortgages
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	27,193,000	[1]	27,296,000	[1]	27,218,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	30,200,000	[1]	30,209,000	[1]	30,434,000	[1]
financing receivables, modifications, number of contracts at period end	347		333		343
Total consumer
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	79,936,000	[1]	70,071,000	[1]	77,153,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	83,985,000	[1]	74,447,000	[1]	81,463,000	[1]
financing receivables, modifications, number of contracts at period end	2,322		2,404		2,309
Originated Loans Commercial | Commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	16,923,000	[1]	5,588,000	[1]	7,123,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	23,666,000	[1]	12,546,000	[1]	13,887,000	[1]
financing receivables, modifications, number of contracts at period end	47		40		41
Originated Loans Commercial | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	12,076,000	[1]	16,432,000	[1]	17,607,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	17,325,000	[1]	17,079,000	[1]	22,645,000	[1]
financing receivables, modifications, number of contracts at period end	64		57		67
Originated Loans Commercial | Commercial Real Estate Construction Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	0	[1]	2,769,000	[1]	0	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	0	[1]	2,777,000	[1]	0	[1]
financing receivables, modifications, number of contracts at period end	31		32		31
Originated Loans Commercial | Total commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	28,999,000	[1]	24,789,000	[1]	24,730,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	40,991,000	[1]	32,402,000	[1]	36,532,000	[1]
financing receivables, modifications, number of contracts at period end	142		129		139
Originated Consumer Loans | Installment
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	26,882,000	[1]	25,818,000	[1]	24,905,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	27,528,000	[1]	26,911,000	[1]	25,608,000	[1]
financing receivables, modifications, number of contracts at period end	1,186		1,434		1,205
Originated Consumer Loans | Home Equity Line of Credit
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	7,632,000	[1]	6,931,000	[1]	7,379,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	7,877,000	[1]	7,243,000	[1]	7,629,000	[1]
financing receivables, modifications, number of contracts at period end	276		244		270
Originated Consumer Loans | Consumer Credit Card
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	815,000	[1]	1,034,000	[1]	854,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	815,000	[1]	1,034,000	[1]	854,000	[1]
financing receivables, modifications, number of contracts at period end	230		278		238
Originated Consumer Loans | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	24,822,000	[1]	26,199,000	[1]	25,251,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	27,612,000	[1]	29,006,000	[1]	28,277,000	[1]
financing receivables, modifications, number of contracts at period end	316		320		315
Originated Consumer Loans | Total consumer
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	60,151,000	[1]	59,982,000	[1]	58,389,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	63,832,000	[1]	64,194,000	[1]	62,368,000	[1]
financing receivables, modifications, number of contracts at period end	2,008		2,276		2,028
Originated Loans
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	89,150,000	[1]	84,771,000	[1]	83,119,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	104,823,000	[1]	96,596,000	[1]	98,900,000	[1]
financing receivables, modifications, number of contracts at period end	2,150		2,405		2,167
Acquired Loans
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	13,146,000	[1]	5,181,000	[1]	12,100,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	13,692,000	[1]	5,337,000	[1]	12,474,000	[1]
financing receivables, modifications, number of contracts at period end	247		76		216
Acquired Loans | Commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,000		5,000		18,000
Financing Receiables, Modifications, Unpaid Principal Balance	3,000		5,000		19,000
financing receivables, modifications, number of contracts at period end	1		1		2
Acquired Loans | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,453,000	[1]	1,695,000	[1]	2,542,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	2,635,000	[1]	1,687,000	[1]	2,595,000	[1]
financing receivables, modifications, number of contracts at period end	3		1		3
Acquired Loans | Commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			1,700,000	[1]	2,560,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance			1,692,000	[1]	2,614,000	[1]
financing receivables, modifications, number of contracts at period end			2		5
Acquired Loans | Total commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,455,000		1,700,000		2,560,000
Financing Receiables, Modifications, Unpaid Principal Balance	2,638,000
financing receivables, modifications, number of contracts at period end	4
Acquired Loans | installment
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	1,195,000		797,000		975,000
Financing Receiables, Modifications, Unpaid Principal Balance	1,281,000		828,000		1,054,000
financing receivables, modifications, number of contracts at period end	51		23		40
Acquired Loans | Home Equity Line of Credit
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	7,310,000	[1]	1,926,000	[1]	6,932,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	7,370,000	[1]	1,953,000	[1]	6,983,000	[1]
financing receivables, modifications, number of contracts at period end	162		40		145
Acquired Loans | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,186,000		758,000	[1]	1,633,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	2,403,000		864,000	[1]	1,823,000	[1]
financing receivables, modifications, number of contracts at period end	30		11		26
Acquired Loans | Total consumer
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	10,691,000	[1]	3,481,000		9,540,000
Financing Receiables, Modifications, Unpaid Principal Balance	11,054,000	[1]	3,645,000		9,860,000
financing receivables, modifications, number of contracts at period end	243		74		211
Covered Loans Commercial | Commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	0	[1]	677,000	[1]	177,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	1,355,000	[1]	2,232,000	[1]	1,589,000	[1]
financing receivables, modifications, number of contracts at period end	8		4		8
Covered Loans Commercial | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	23,895,000	[1]	39,939,000	[1]	25,499,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	39,596,000	[1]	56,485,000	[1]	42,226,000	[1]
financing receivables, modifications, number of contracts at period end	24		25		24
Covered Loans Commercial | Commercial Real Estate Construction Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	346,000	[1]	2,560,000	[1]	339,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	9,552,000	[1]	21,340,000	[1]	9,552,000	[1]
financing receivables, modifications, number of contracts at period end	9		10		9
Covered Loans Commercial | Total commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	24,241,000	[1]	43,176,000	[1]	26,015,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	50,503,000	[1]	80,057,000	[1]	53,367,000	[1]
financing receivables, modifications, number of contracts at period end	41		39		41
Covered Consumer Loans
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	9,094,000		6,608,000		9,224,000
Covered Consumer Loans | Home Equity Line of Credit
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	8,909,000	[1]	6,269,000	[1]	8,890,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	8,914,000	[1]	6,269,000	[1]	8,901,000	[1]
financing receivables, modifications, number of contracts at period end	70		52		68
Covered Consumer Loans | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	185,000	[1]	339,000		334,000
Financing Receiables, Modifications, Unpaid Principal Balance	185,000	[1]
financing receivables, modifications, number of contracts at period end	1
Covered Consumer Loans | Total consumer
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			6,608,000
Financing Receiables, Modifications, Unpaid Principal Balance			6,608,000
financing receivables, modifications, number of contracts at period end			54
Covered TDR Loans
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	33,335,000	[1]	49,784,000	[1]	35,239,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	59,602,000	[1]	86,665,000	[1]	62,602,000	[1]
financing receivables, modifications, number of contracts at period end	112		93		111
Covered TDR Loans | Total commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			43,176,000
Covered TDR Loans | Residential Real Estate
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment			339,000
Financing Receiables, Modifications, Unpaid Principal Balance			339,000
financing receivables, modifications, number of contracts at period end			2
Covered TDR Loans | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment					334,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance					334,000	[1]
financing receivables, modifications, number of contracts at period end					2
Covered TDR Loans | Total consumer
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	9,094,000	[1]			9,224,000	[1]
Financing Receiables, Modifications, Unpaid Principal Balance	$ 9,099,000	[1]			$ 9,235,000	[1]
financing receivables, modifications, number of contracts at period end	71				70

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