The amount of expense charged against earnings by an entity to record deferred gains and losses on hedge instruments.

No definition available.

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- Definition

Change in Fair Value on Loans Held for Sale

+ References

No definition available.

+ Details

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- Definition

Exposure to counterparties relating to customer related positions.

+ References

No definition available.

+ Details

Name:	indb_ExposureToCounterpartiesRelatingToCustomerRelatedPositions
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Balance Type:	debit
Period Type:	instant

- Definition

Exposure to Institutional Counterparties

+ References

No definition available.

+ Details

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Namespace Prefix:	indb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loss on termination of derivatives

+ References

No definition available.

+ Details

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

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- Details

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- Definition

Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

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Derivatives and Hedging Activities (Textual) (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative [Line Items]
Change in fair value on loans held for sale									$ 18,000	$ 1,000	$ (141,000)
Net amortization income									244,000
Exposure to Institutional Counterparties	272,000				3,400,000				272,000	3,400,000
Maximum length of time Company is currently hedging its exposure	4 years
Interest expense	2,700,000
Customer related positions	18,900,000				13,600,000				18,900,000	13,600,000
Loss on termination of derivatives	$ 0indb_Lossonterminationofderivatives	$ 0indb_Lossonterminationofderivatives	$ 1,122,000indb_Lossonterminationofderivatives	$ 0indb_Lossonterminationofderivatives	$ 0indb_Lossonterminationofderivatives	$ 0indb_Lossonterminationofderivatives	$ 0indb_Lossonterminationofderivatives	$ 0indb_Lossonterminationofderivatives	$ 1,100,000indb_Lossonterminationofderivatives