INCOME TAXES (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	$ 0	$ 160,000	$ 343,000

Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions, federal benefit of state tax amount

No definition available.

Name:	indb_UnrecognizedTaxBenefitsIncreaseResultingfromCurrentPeriodTaxPositionsfederalbenefitofstatetaxamount
Namespace Prefix:	indb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration