XML 36 R77.htm IDEA: XBRL DOCUMENT
v3.20.1

Derivatives and Hedging Activities (Derivative Positions for Interest Rate Swaps which Qualify as Hedges) (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Amortization Of Deferred Hedge Gains Losses |  | $ 0 |  |  |
Change in Fair Value on Loans Held for Sale |  | (914,000) | $ 1,000 |  | $ 1,000
Fair Value Hedges, Net |  | 0 |  | $ 0 |
Interest rate collars on loans [Member] |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Derivative, Notional Amount |  | $ 400,000,000 |  | $ 400,000,000 |
Derivative, Average Remaining Maturity |  | 3 years 4 months 28 days |  | 3 years 7 months 28 days |
Derivative, Average Variable Interest Rate |  | 0.81% |  | 1.76% |
Fair Value | [1] | $ 25,573,000 |  | $ 9,896,000 |
Derivative, Average Cap Interest Rate |  | 2.73% |  | 3.02% |
Derivative, Average Floor Interest Rate |  | 2.20% |  | 2.51% |
Interest rate swaps on loans [Member] |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Derivative, Notional Amount |  | $ 450,000,000 |  | $ 450,000,000 |
Derivative, Average Remaining Maturity |  | 3 years 4 months 28 days |  | 3 years 7 months 28 days |
Derivative, Average Variable Interest Rate |  | 0.86% |  | 1.76% |
Derivative, Average Fixed Interest Rate |  | 2.37% |  | 2.37% |
Fair Value | [1] | $ 31,701,000 |  | $ 12,907,000 |
Interest rate swaps on borrowings [Member] |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Derivative, Notional Amount |  | $ 175,000,000 |  | $ 75,000,000 |
Derivative, Average Remaining Maturity |  | 2 years 2 months 12 days |  | 2 years 2 months 4 days |
Derivative, Average Variable Interest Rate |  | 1.28% |  | 1.90% |
Derivative, Average Fixed Interest Rate |  | 0.94% |  | 1.53% |
Fair Value | [1] | $ (1,790,000) |  | $ 140,000 |
Interest rate swaps |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Derivative, Notional Amount |  | 1,025,000,000 |  | 925,000,000 |
Fair Value | [1] | $ 55,484,000 |  | $ 22,943,000 |
[1] | Beginning in 2020, the Company made an election to include accrued interest within fair value balances.

X
- Definition The amount of expense charged against earnings by an entity to record deferred gains and losses on hedge instruments. + References No definition available. + Details
Name: | indb_AmortizationOfDeferredHedgeGainsLosses
Namespace Prefix: | indb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Change in Fair Value on Loans Held for Sale + References No definition available. + Details
Name: | indb_ChangeInFairValueOnLoansHeldForSale
Namespace Prefix: | indb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Average cap rate on a group of interest rate derivatives, such as interest rate caps or collars. If market rates exceed the cap rate, a payment or receipt is triggered on the contract. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageCapInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Average fixed interest rate related to the group of interest rate derivatives. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageFixedInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Average floor rate on a group of interest rate derivatives, such as interest rate floor or collars. If market rates fall below the floor rate, a payment or receipt is triggered on the contract. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageFloorInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageRemainingMaturity1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Average variable interest rate related to the group of interest rate derivatives. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageVariableInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeNetAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Net fair value of all derivative instruments designated as fair value hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958 + Details
Name: | us-gaap_FairValueHedgesAtFairValueNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=indb_InterestratecollarsonloansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=indb_InterestrateswapsonloansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=indb_InterestrateswapsonborrowingsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |