Name:	indb_BusinessAcquisitionEquityInterestIssuedOrIssuableNumberOfSharesOfCompanyStockIssuedForEachShareOfAcquireeStock
Namespace Prefix:	indb_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

No definition available.

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

Business Combination, Increase in Acquirer Outstanding Shares

No definition available.

Name:	indb_BusinessCombinationIncreaseInAcquirerOutstandingShares
Namespace Prefix:	indb_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

Name:	us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.