Age Analysis of Past Due Financing receivables (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014 loan	Dec. 31, 2013 loan
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	112	209
Principal Balance 30-59 Days	$ 20,609	$ 15,925
Number of Loans 60-89 Days	47	60
Principal Balance 60-89 Days	4,725	3,498
Number of Loans 90 Days or More	110	161
Principal Balance 90 Days or More	14,270	21,116
Number of Loans Total Past Due	269	430
Principal Balance Total Past Due	39,604	40,539
Current	4,931,129	4,677,768
Loans Receivable, Gross, Commercial, Construction	265,994	223,859
Loans Receivable, Gross, Commercial and Industrial	860,839	784,202
Loans and Leases Receivable, Gross, Consumer, Other	17,208	20,162
Loans Receivable, Gross, Commercial, Mortgage	2,347,323	2,249,260
Loans and Leases Receivable, Gross, Consumer, Mortgage	530,259	541,443
Small Business	85,247indb_SmallBusiness	77,240indb_SmallBusiness
Total Financing Receivables	4,970,733	4,718,307
Recorded Investment >90 Days and Accruing	119	525
Commercial and Industrial [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	18	9
Principal Balance 30-59 Days	3,192	743
Number of Loans 60-89 Days	10	6
Principal Balance 60-89 Days	1,007	327
Number of Loans 90 Days or More	19	20
Principal Balance 90 Days or More	2,320	3,763
Number of Loans Total Past Due	47	35
Principal Balance Total Past Due	6,519	4,833
Current	854,320	779,369
Total Financing Receivables	860,839
Commercial Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	19	21
Principal Balance 30-59 Days	13,428	8,643
Number of Loans 60-89 Days	6	2
Principal Balance 60-89 Days	1,480	356
Number of Loans 90 Days or More	16	30
Principal Balance 90 Days or More	4,225	8,155
Number of Loans Total Past Due	41	53
Principal Balance Total Past Due	19,133	17,154
Current	2,328,190	2,232,106
Total Financing Receivables	2,347,323
Commercial Construction [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	1	1
Principal Balance 30-59 Days	506	847
Number of Loans 90 Days or More	1	1
Principal Balance 90 Days or More	311	100
Number of Loans Total Past Due	2	2
Principal Balance Total Past Due	817	947
Current	265,177	222,912
Total Financing Receivables	265,994
Small Business [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	7	18
Principal Balance 30-59 Days	21	353
Number of Loans 60-89 Days	8	6
Principal Balance 60-89 Days	113	227
Number of Loans 90 Days or More	7	14
Principal Balance 90 Days or More	173	247
Number of Loans Total Past Due	22	38
Principal Balance Total Past Due	307	827
Current	84,940	76,413
Total Financing Receivables	85,247
Residential Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	13	23
Principal Balance 30-59 Days	1,670	2,903
Number of Loans 60-89 Days	10	8
Principal Balance 60-89 Days	1,798	1,630
Number of Loans 90 Days or More	36	39
Principal Balance 90 Days or More	4,826	6,648
Number of Loans Total Past Due	59	70
Principal Balance Total Past Due	8,294	11,181
Current	521,965	530,262
Total Financing Receivables	530,259
Recorded Investment >90 Days and Accruing	106	462
Home Equity [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	20	27
Principal Balance 30-59 Days	1,559	1,922
Number of Loans 60-89 Days	7	8
Principal Balance 60-89 Days	307	852
Number of Loans 90 Days or More	23	23
Principal Balance 90 Days or More	2,402	2,055
Number of Loans Total Past Due	50	58
Principal Balance Total Past Due	4,268	4,829
Current	859,595	817,312
Total Financing Receivables	863,863	822,141
Consumer - Other [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days	34	110
Principal Balance 30-59 Days	233	514
Number of Loans 60-89 Days	6	30
Principal Balance 60-89 Days	20	106
Number of Loans 90 Days or More	8	34
Principal Balance 90 Days or More	13	148
Number of Loans Total Past Due	48	174
Principal Balance Total Past Due	266	768
Current	16,942	19,394
Total Financing Receivables	17,208
Recorded Investment >90 Days and Accruing	$ 13	$ 63

Number of financing receivables equal to greater than ninety days.

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Number of financing receivables sixty to eighty nine days past due.

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Number of Financing Receivables Thirty to Fifty Nine Days Past Due.

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Commercial and industrial and commercial real estate loans made with businesses with commercial credit requirements of $250,000 and revenues typically less than or equal to $2.5 million.

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Financing receivables that are less than 60 days past due but more than 29 days past due.

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount before allowance of consumer mortgage. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes subordinated loans such as home equity lines of credit and loans and leases covered under loss sharing agreements.

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Amount before allowance of consumer loans and leases not otherwise specified in the taxonomy. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reflects the aggregate gross carrying amount of all loans and leases held in portfolio, not otherwise categorized (such as commercial, consumer, or foreign), prior to deducting deferred income and the allowance for losses on loans and leases, not otherwise categorized (such as commercial, consumer, or foreign).

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Amount before allowance of loans issued to commercial and industrial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes real estate loans and loans covered under loss sharing agreements.

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Amount before allowance of commercial construction loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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