Loans, Allowance for Loan Losses and Credit Quality (Int Inc. Recognized on Impaired Loans by Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Interest income recognized on impaired loans
Average Recorded Investment	$ 63,152	$ 72,085
Interest Income Recognized	851	916
WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	34,841	36,367
Interest Income Recognized	480	516
WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	28,311	35,718
Interest Income Recognized	371	400
Commercial and Industrial [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	3,862	5,409
Interest Income Recognized	57	68
Commercial and Industrial [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	2,871	3,516
Interest Income Recognized	36	39
Commercial Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	21,137	21,522
Interest Income Recognized	310	333
Commercial Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	10,872	16,640
Interest Income Recognized	137	207
Commercial Construction [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	311	100
Interest Income Recognized	3	3
Small Business [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	722	1,456
Interest Income Recognized	11	24
Small Business [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	356	460
Interest Income Recognized	6	8
Residential Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	3,474	2,938
Interest Income Recognized	40	28
Residential Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	12,410	13,679
Interest Income Recognized	173	132
Consumer - Home Equity [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	4,749	4,529
Interest Income Recognized	52	52
Consumer - Home Equity [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	1,289	623
Interest Income Recognized	14	7
Consumer - Other [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	586	413
Interest Income Recognized	7	8
Consumer - Other [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Interest income recognized on impaired loans
Average Recorded Investment	513	800
Interest Income Recognized	$ 5	$ 7

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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