Loans, Allowance for Credit Losses, and Credit Quality Impaired Loans Recorded Investment, Unpaid Principal Balance, Related Allowance, Average Recorded Investment, and Interest Income Recognized (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	$ 263,163,000	$ 275,629,000
Unpaid Principal Balance	293,587,000	310,811,000
Related Allowance	37,386,000	50,431,000
YTD Average Recorded Investment	266,437,000	290,370,000
YTD Interest Income Recognized	1,661,000	9,384,000
Interest income recognized on accruing restructured loans	1,000,000	5,000,000
Fair Value Mark	77.00%	72.00%
Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	206,632,000	232,166,000
Unpaid Principal Balance	222,893,000	253,186,000
Related Allowance	37,386,000	50,431,000
YTD Average Recorded Investment	208,242,000	242,219,000
YTD Interest Income Recognized	1,522,000	8,797,000
Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	56,531,000	43,463,000
Unpaid Principal Balance	70,694,000	57,625,000
Related Allowance	0	0
YTD Average Recorded Investment	58,195,000	48,151,000
YTD Interest Income Recognized	139,000	587,000
Commercial And Industrial Financing Receivable [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	88,086,000	83,555,000
Unpaid Principal Balance	98,247,000	93,048,000
Related Allowance	7,629,000	16,467,000
YTD Average Recorded Investment	89,376,000	88,855,000
YTD Interest Income Recognized	369,000	3,221,000
Commercial And Industrial Financing Receivable [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	58,274,000	76,433,000
Unpaid Principal Balance	59,809,000	80,414,000
Related Allowance	7,629,000	16,467,000
YTD Average Recorded Investment	58,815,000	80,004,000
YTD Interest Income Recognized	265,000	3,139,000
Commercial And Industrial Financing Receivable [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	29,812,000	7,122,000
Unpaid Principal Balance	38,438,000	12,634,000
Related Allowance	0	0
YTD Average Recorded Investment	30,561,000	8,851,000
YTD Interest Income Recognized	104,000	82,000
Commercial Real Estate Owner Occupied Portfolio [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	31,641,000	36,279,000
Unpaid Principal Balance	36,062,000	40,826,000
Related Allowance	2,059,000	3,221,000
YTD Average Recorded Investment	32,201,000	38,848,000
YTD Interest Income Recognized	123,000	900,000
Commercial Real Estate Owner Occupied Portfolio [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	20,147,000	19,839,000
Unpaid Principal Balance	22,390,000	21,807,000
Related Allowance	2,059,000	3,221,000
YTD Average Recorded Investment	20,448,000	20,878,000
YTD Interest Income Recognized	123,000	681,000
Commercial Real Estate Owner Occupied Portfolio [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	11,494,000	16,440,000
Unpaid Principal Balance	13,672,000	19,019,000
Related Allowance	0	0
YTD Average Recorded Investment	11,753,000	17,970,000
YTD Interest Income Recognized	0	219,000
Finance Leases Financing Receivable [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	1,720,000	1,801,000
Unpaid Principal Balance	1,720,000	1,801,000
Related Allowance	510,000	574,000
YTD Average Recorded Investment	1,747,000	2,009,000
YTD Interest Income Recognized	0	0
Finance Leases Financing Receivable [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	1,720,000	1,801,000
Unpaid Principal Balance	1,720,000	1,801,000
Related Allowance	510,000	574,000
YTD Average Recorded Investment	1,747,000	2,009,000
YTD Interest Income Recognized	0	0
Finance Leases Financing Receivable [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
YTD Average Recorded Investment	0	0
YTD Interest Income Recognized	0	0
Commercial And Business Lending [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	121,447,000	121,635,000
Unpaid Principal Balance	136,029,000	135,675,000
Related Allowance	10,198,000	20,262,000
YTD Average Recorded Investment	123,324,000	129,712,000
YTD Interest Income Recognized	492,000	4,121,000
Commercial And Business Lending [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	80,141,000	98,073,000
Unpaid Principal Balance	83,919,000	104,022,000
Related Allowance	10,198,000	20,262,000
YTD Average Recorded Investment	81,010,000	102,891,000
YTD Interest Income Recognized	388,000	3,820,000
Commercial And Business Lending [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	41,306,000	23,562,000
Unpaid Principal Balance	52,110,000	31,653,000
Related Allowance	0	0
YTD Average Recorded Investment	42,314,000	26,821,000
YTD Interest Income Recognized	104,000	301,000
Commercial Real Estate Investor Portfolio Segment [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	36,517,000	45,812,000
Unpaid Principal Balance	42,031,000	54,905,000
Related Allowance	2,028,000	3,587,000
YTD Average Recorded Investment	37,292,000	48,671,000
YTD Interest Income Recognized	295,000	1,383,000
Commercial Real Estate Investor Portfolio Segment [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	32,244,000	36,841,000
Unpaid Principal Balance	35,466,000	40,869,000
Related Allowance	2,028,000	3,587,000
YTD Average Recorded Investment	32,338,000	38,657,000
YTD Interest Income Recognized	287,000	1,250,000
Commercial Real Estate Investor Portfolio Segment [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	4,273,000	8,971,000
Unpaid Principal Balance	6,565,000	14,036,000
Related Allowance	0	0
YTD Average Recorded Investment	4,954,000	10,014,000
YTD Interest Income Recognized	8,000	133,000
Commercial Real Estate Construction Financing Receivable [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	6,140,000	6,126,000
Unpaid Principal Balance	8,313,000	9,725,000
Related Allowance	1,041,000	1,095,000
YTD Average Recorded Investment	6,098,000	7,059,000
YTD Interest Income Recognized	17,000	105,000
Commercial Real Estate Construction Financing Receivable [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	2,967,000	3,043,000
Unpaid Principal Balance	4,354,000	5,910,000
Related Allowance	1,041,000	1,095,000
YTD Average Recorded Investment	2,987,000	3,818,000
YTD Interest Income Recognized	17,000	105,000
Commercial Real Estate Construction Financing Receivable [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	3,173,000	3,083,000
Unpaid Principal Balance	3,959,000	3,815,000
Related Allowance	0	0
YTD Average Recorded Investment	3,111,000	3,241,000
YTD Interest Income Recognized	0	0
Commercial Real Estate Lending [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	42,657,000	51,938,000
Unpaid Principal Balance	50,344,000	64,630,000
Related Allowance	3,069,000	4,682,000
YTD Average Recorded Investment	43,390,000	55,730,000
YTD Interest Income Recognized	312,000	1,488,000
Commercial Real Estate Lending [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	35,211,000	39,884,000
Unpaid Principal Balance	39,820,000	46,779,000
Related Allowance	3,069,000	4,682,000
YTD Average Recorded Investment	35,325,000	42,475,000
YTD Interest Income Recognized	304,000	1,355,000
Commercial Real Estate Lending [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	7,446,000	12,054,000
Unpaid Principal Balance	10,524,000	17,851,000
Related Allowance	0	0
YTD Average Recorded Investment	8,065,000	13,255,000
YTD Interest Income Recognized	8,000	133,000
Commercial Financing Receivable [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	164,104,000	173,573,000
Unpaid Principal Balance	186,373,000	200,305,000
Related Allowance	13,267,000	24,944,000
YTD Average Recorded Investment	166,714,000	185,442,000
YTD Interest Income Recognized	804,000	5,609,000
Commercial Financing Receivable [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	115,352,000	137,957,000
Unpaid Principal Balance	123,739,000	150,801,000
Related Allowance	13,267,000	24,944,000
YTD Average Recorded Investment	116,335,000	145,366,000
YTD Interest Income Recognized	692,000	5,175,000
Commercial Financing Receivable [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	48,752,000	35,616,000
Unpaid Principal Balance	62,634,000	49,504,000
Related Allowance	0	0
YTD Average Recorded Investment	50,379,000	40,076,000
YTD Interest Income Recognized	112,000	434,000
Home Equity [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	30,166,000	31,807,000
Unpaid Principal Balance	33,590,000	35,533,000
Related Allowance	12,360,000	13,015,000
YTD Average Recorded Investment	30,475,000	33,226,000
YTD Interest Income Recognized	328,000	1,528,000
Home Equity [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	29,430,000	31,021,000
Unpaid Principal Balance	32,827,000	34,727,000
Related Allowance	12,360,000	13,015,000
YTD Average Recorded Investment	29,709,000	32,375,000
YTD Interest Income Recognized	326,000	1,510,000
Home Equity [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	736,000	786,000
Unpaid Principal Balance	763,000	806,000
Related Allowance	0	0
YTD Average Recorded Investment	766,000	851,000
YTD Interest Income Recognized	2,000	18,000
Installment and Credit Cards [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	1,406,000	1,587,000
Unpaid Principal Balance	1,618,000	1,795,000
Related Allowance	264,000	308,000
YTD Average Recorded Investment	1,437,000	1,736,000
YTD Interest Income Recognized	9,000	58,000
Installment and Credit Cards [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	1,406,000	1,587,000
Unpaid Principal Balance	1,618,000	1,795,000
Related Allowance	264,000	308,000
YTD Average Recorded Investment	1,437,000	1,736,000
YTD Interest Income Recognized	9,000	58,000
Installment and Credit Cards [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
YTD Average Recorded Investment	0	0
YTD Interest Income Recognized	0	0
Residential, Prime, Financing Receivable [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	67,487,000	68,662,000
Unpaid Principal Balance	72,006,000	73,178,000
Related Allowance	11,495,000	12,164,000
YTD Average Recorded Investment	67,811,000	69,966,000
YTD Interest Income Recognized	520,000	2,189,000
Residential, Prime, Financing Receivable [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	60,444,000	61,601,000
Unpaid Principal Balance	64,709,000	65,863,000
Related Allowance	11,495,000	12,164,000
YTD Average Recorded Investment	60,761,000	62,742,000
YTD Interest Income Recognized	495,000	2,054,000
Residential, Prime, Financing Receivable [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	7,043,000	7,061,000
Unpaid Principal Balance	7,297,000	7,315,000
Related Allowance	0	0
YTD Average Recorded Investment	7,050,000	7,224,000
YTD Interest Income Recognized	25,000	135,000
Consumer Loan [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	99,059,000	102,056,000
Unpaid Principal Balance	107,214,000	110,506,000
Related Allowance	24,119,000	25,487,000
YTD Average Recorded Investment	99,723,000	104,928,000
YTD Interest Income Recognized	857,000	3,775,000
Consumer Loan [Member] | Loans With Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	91,280,000	94,209,000
Unpaid Principal Balance	99,154,000	102,385,000
Related Allowance	24,119,000	25,487,000
YTD Average Recorded Investment	91,907,000	96,853,000
YTD Interest Income Recognized	830,000	3,622,000
Consumer Loan [Member] | Loans With No Related Allowance [Member]
Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans
Recorded Investment	7,779,000	7,847,000
Unpaid Principal Balance	8,060,000	8,121,000
Related Allowance	0	0
YTD Average Recorded Investment	7,816,000	8,075,000
YTD Interest Income Recognized	$ 27,000	$ 153,000