XML 39 R73.htm IDEA: XBRL DOCUMENT
v3.20.1

Earnings Per Share Antidilutive Securities excluded from the Computaion of Earnings Per Share (Details) - shares | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Share-based Payment Arrangement, Option [Member] |  |
Stock Option [Line Items] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 0 | 0
Performance Shares [Member] |  |
Stock Option [Line Items] |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 5,431 | 6,890

X
- Definition [Line Items] for Stock Option [Table] + References No definition available. + Details
Name: | indb_StockOptionLineItems
Namespace Prefix: | indb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
Name: | us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | indb_StockOptionsAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | indb_PerformancebasedrestrictedstockAxis=us-gaap_PerformanceSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |