Loans, Allowance for Loan Losses, and Credit Quality Troubled Debt Restructurings Performing and Nonaccrual (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	$ 116,924	$ 123,985
Nonaccrual Restructured Loans	74,231	59,585
Commercial and Industrial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	27,776	32,517
Nonaccrual Restructured Loans	8,781	6,900
Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	11,579	13,009
Nonaccrual Restructured Loans	15,697	10,999
Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	46,020	44,946
Nonaccrual Restructured Loans	14,619	18,069
Commercial Real Estate Construction Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	2,954	3,793
Nonaccrual Restructured Loans	2,558	2,065
Home Equity Port Folio Segments [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	9,572	9,633
Nonaccrual Restructured Loans	7,785	5,419
Installment [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	225	246
Nonaccrual Restructured Loans	419	451
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Performing Restructured Loans	18,798	19,841
Nonaccrual Restructured Loans	$ 24,372	$ 15,682