$INDB
INDEPENDENT BANK CORP Stock $indb

$indb Overview Financials Valuation SEC Filings Company Website

2020 Q3 Form 10-Q Financial Statement

#000077690120000175 Filed on November 05, 2020

Income Statement

Concept	2020 Q3	2019 Q3	2019 Q2
Revenue	$97.92M	$119.6M	$122.1M
YoY Change	-18.14%	44.34%	54.29%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$7.000M	$8.900M	$1.400M
YoY Change	-21.35%	117.07%	-63.16%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$7.036M	$15.03M	$16.13M
YoY Change	-53.17%	126.26%	168.79%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$46.07M	$68.88M	$40.64M
YoY Change	-33.11%	60.25%	0.66%
Income Tax	$11.20M	$17.04M	$10.01M
% Of Pretax Income	24.31%	24.73%	24.63%
Net Earnings	$34.87M	$51.85M	$30.63M
YoY Change	-32.74%	57.03%	-1.57%
Net Earnings / Revenue	35.61%	43.34%	25.08%
Basic Earnings Per Share	$1.06	$1.51	$0.89
Diluted Earnings Per Share	$1.06	$1.51	$0.89
COMMON SHARES
Basic Shares Outstanding	32.95M shares	34.36M shares	34.31M shares
Diluted Shares Outstanding	32.98M shares	34.40M shares	34.36M shares

Balance Sheet

Concept	2020 Q3	2019 Q3	2019 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents
Short-Term Investments	$1.107B	$1.192B	$1.213B
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$121.8M	$125.0M	$123.4M
YoY Change	-2.57%	30.32%	28.73%
Goodwill	$506.2M	$504.6M	$504.6M
YoY Change	0.33%	117.67%	117.67%
Intangibles	$24.54M
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$13.17B	$11.54B	$11.60B
YoY Change	14.17%	37.77%	38.45%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses		$53.00M	$53.00M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities		$53.00M	$53.00M
YoY Change		-62.41%	-62.68%
LONG-TERM LIABILITIES
Long-Term Debt	$150.0M	$222.0M	$222.0M
YoY Change	-32.43%	105.56%	105.56%
Other Long-Term Liabilities	$337.0M	$184.0M	$106.0M
YoY Change	83.15%	82.18%	17.78%
Total Long-Term Liabilities	$487.0M	$406.0M	$328.0M
YoY Change	19.95%	94.26%	65.66%
TOTAL LIABILITIES
Total Short-Term Liabilities		$53.00M	$53.00M
Total Long-Term Liabilities	$487.0M	$406.0M	$328.0M
Total Liabilities	$11.48B	$9.856B	$9.967B
YoY Change	16.51%	33.61%	34.62%
SHAREHOLDERS EQUITY
Retained Earnings	$696.5M	$621.8M	$585.1M
YoY Change	12.02%	17.89%	15.88%
Common Stock	$328.0K	$342.0K	$342.0K
YoY Change	-4.09%	24.82%	24.82%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.690B	$1.682B	$1.636B
YoY Change
Total Liabilities & Shareholders Equity	$13.17B	$11.54B	$11.60B
YoY Change	14.17%	37.77%	38.45%

Cashflow Statement

Concept	2020 Q3	2019 Q3	2019 Q2
OPERATING ACTIVITIES
Net Income	$34.87M	$51.85M	$30.63M
YoY Change	-32.74%	57.03%	-1.57%
Depreciation, Depletion And Amortization	$7.000M	$8.900M	$1.400M
YoY Change	-21.35%	117.07%	-63.16%
Cash From Operating Activities	$24.20M	$152.1M	-$49.10M
YoY Change	-84.09%	320.17%	-245.7%
INVESTING ACTIVITIES
Capital Expenditures	-$3.100M	-$4.800M	-$3.300M
YoY Change	-35.42%	100.0%	13.79%
Acquisitions
YoY Change
Other Investing Activities	$21.20M	$77.10M	-$16.30M
YoY Change	-72.5%	-233.39%	-87.23%
Cash From Investing Activities	$18.10M	$72.30M	-$19.50M
YoY Change	-74.97%	-220.1%	-85.06%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	120.0M	-199.2M	-29.70M
YoY Change	-160.24%	312.42%	-111.68%
NET CHANGE
Cash From Operating Activities	24.20M	152.1M	-49.10M
Cash From Investing Activities	18.10M	72.30M	-19.50M
Cash From Financing Activities	120.0M	-199.2M	-29.70M
Net Change In Cash	162.3M	25.20M	-98.30M
YoY Change	544.05%	-134.85%	-162.41%
FREE CASH FLOW
Cash From Operating Activities	$24.20M	$152.1M	-$49.10M
Capital Expenditures	-$3.100M	-$4.800M	-$3.300M
Free Cash Flow	$27.30M	$156.9M	-$45.80M
YoY Change	-82.6%	306.48%	-225.14%

Facts In Submission

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	dei	Amendment Flag AmendmentFlag	false
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
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	dei	City Area Code CityAreaCode	(781)
	dei	Local Phone Number LocalPhoneNumber	878-6100
	dei	Entity Address Address Line1 EntityAddressAddressLine1	2036 Washington Street,
	dei	Entity Address City Or Town EntityAddressCityOrTown	Hanover,
	dei	Entity Address State Or Province EntityAddressStateOrProvince	MA
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	02339
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	dei	Document Transition Report DocumentTransitionReport	false
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	dei	Entity Registrant Name EntityRegistrantName	Independent Bank Corp.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MA
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CY2019Q3	us-gaap	Interest Income Federal Funds Sold InterestIncomeFederalFundsSold	680000	USD
	us-gaap	Interest Income Federal Funds Sold InterestIncomeFederalFundsSold	546000	USD
	us-gaap	Interest Income Federal Funds Sold InterestIncomeFederalFundsSold	1753000	USD
CY2020Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	97919000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	119624000	USD
	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	305264000	USD
	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	333311000	USD
CY2020Q3	us-gaap	Interest Expense Deposits InterestExpenseDeposits	5432000	USD
CY2019Q3	us-gaap	Interest Expense Deposits InterestExpenseDeposits	11846000	USD
	us-gaap	Interest Expense Deposits InterestExpenseDeposits	23351000	USD
	us-gaap	Interest Expense Deposits InterestExpenseDeposits	30052000	USD
CY2020Q3	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	1604000	USD
CY2019Q3	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	3180000	USD
	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	5628000	USD
	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	10117000	USD
CY2020Q3	us-gaap	Interest Expense InterestExpense	7036000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	15026000	USD
	us-gaap	Interest Expense InterestExpense	28979000	USD
	us-gaap	Interest Expense InterestExpense	40169000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	90883000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	104598000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	276285000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	293142000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	7500000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	52500000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2000000	USD
CY2020Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	83383000	USD
CY2019Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	104598000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	223785000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	291142000	USD
CY2020Q3	indb	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	3428000	USD
CY2019Q3	indb	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	5299000	USD
	indb	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	11227000	USD
	indb	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	14785000	USD
CY2020Q3	indb	Interchange And Atm Fees InterchangeAndAtmFees	3044000	USD
CY2019Q3	indb	Interchange And Atm Fees InterchangeAndAtmFees	6137000	USD
	indb	Interchange And Atm Fees InterchangeAndAtmFees	13154000	USD
	indb	Interchange And Atm Fees InterchangeAndAtmFees	16447000	USD
CY2020Q3	us-gaap	Investment Banking Advisory Brokerage And Underwriting Fees And Commissions InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions	7571000	USD
CY2019Q3	us-gaap	Investment Banking Advisory Brokerage And Underwriting Fees And Commissions InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions	7188000	USD
	us-gaap	Investment Banking Advisory Brokerage And Underwriting Fees And Commissions InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions	21696000	USD
	us-gaap	Investment Banking Advisory Brokerage And Underwriting Fees And Commissions InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions	21089000	USD
CY2020Q3	indb	Fees And Commission Mortgage Banking FeesAndCommissionMortgageBanking	7704000	USD
CY2019Q3	indb	Fees And Commission Mortgage Banking FeesAndCommissionMortgageBanking	3968000	USD
	indb	Fees And Commission Mortgage Banking FeesAndCommissionMortgageBanking	13570000	USD
	indb	Fees And Commission Mortgage Banking FeesAndCommissionMortgageBanking	8184000	USD
CY2020Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1314000	USD
CY2019Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1304000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	3902000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	3572000	USD
CY2020Q3	indb	Gain Realized On Life Insurance Policies GainRealizedOnLifeInsurancePolicies	0	USD
CY2019Q3	indb	Gain Realized On Life Insurance Policies GainRealizedOnLifeInsurancePolicies	434000	USD
	indb	Gain Realized On Life Insurance Policies GainRealizedOnLifeInsurancePolicies	692000	USD
	indb	Gain Realized On Life Insurance Policies GainRealizedOnLifeInsurancePolicies	434000	USD
CY2020Q3	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	2457000	USD
CY2019Q3	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	2739000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	8918000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	4312000	USD
CY2020Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	3829000	USD
CY2019Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	4747000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	10813000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	13174000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	29347000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	31816000	USD
	us-gaap	Noninterest Income NoninterestIncome	83972000	USD
	us-gaap	Noninterest Income NoninterestIncome	81997000	USD
CY2020Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	38409000	USD
CY2019Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	39432000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	113027000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	111401000	USD
CY2020Q3	us-gaap	Occupancy Net OccupancyNet	9273000	USD
CY2019Q3	us-gaap	Occupancy Net OccupancyNet	8555000	USD
	us-gaap	Occupancy Net OccupancyNet	27863000	USD
	us-gaap	Occupancy Net OccupancyNet	24109000	USD
CY2020Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	1567000	USD
CY2019Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	1515000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	4684000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	4883000	USD
CY2020Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1034000	USD
CY2019Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	0	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1537000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1394000	USD
CY2020Q3	us-gaap	Advertising Expense AdvertisingExpense	1215000	USD
CY2019Q3	us-gaap	Advertising Expense AdvertisingExpense	1417000	USD
	us-gaap	Advertising Expense AdvertisingExpense	3107000	USD
	us-gaap	Advertising Expense AdvertisingExpense	3912000	USD
CY2020Q3	us-gaap	Professional Fees ProfessionalFees	1305000	USD
CY2019Q3	us-gaap	Professional Fees ProfessionalFees	1338000	USD
	us-gaap	Professional Fees ProfessionalFees	4244000	USD
	us-gaap	Professional Fees ProfessionalFees	3486000	USD
CY2020Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1428000	USD
CY2019Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1567000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4392000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3996000	USD
CY2020Q3	indb	Availablefor Sale Securities Fixed Income Gross Realized Losses AvailableforSaleSecuritiesFixedIncomeGrossRealizedLosses	0	USD
CY2019Q3	indb	Availablefor Sale Securities Fixed Income Gross Realized Losses AvailableforSaleSecuritiesFixedIncomeGrossRealizedLosses	0	USD
	indb	Availablefor Sale Securities Fixed Income Gross Realized Losses AvailableforSaleSecuritiesFixedIncomeGrossRealizedLosses	0	USD
	indb	Availablefor Sale Securities Fixed Income Gross Realized Losses AvailableforSaleSecuritiesFixedIncomeGrossRealizedLosses	1462000	USD
CY2020Q3	us-gaap	Loss On Contract Termination LossOnContractTermination	684000	USD
CY2019Q3	us-gaap	Loss On Contract Termination LossOnContractTermination	0	USD
	us-gaap	Loss On Contract Termination LossOnContractTermination	684000	USD
	us-gaap	Loss On Contract Termination LossOnContractTermination	0	USD
CY2020Q3	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	0	USD
CY2019Q3	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	705000	USD
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	0	USD
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	26433000	USD
CY2020Q3	indb	Software Maintenance SoftwareMaintenance	1753000	USD
CY2019Q3	indb	Software Maintenance SoftwareMaintenance	1385000	USD
	indb	Software Maintenance SoftwareMaintenance	5218000	USD
	indb	Software Maintenance SoftwareMaintenance	3913000	USD
CY2020Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	9990000	USD
CY2019Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	11619000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	35349000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	31887000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	66658000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	67533000	USD
	us-gaap	Noninterest Expense NoninterestExpense	200105000	USD
	us-gaap	Noninterest Expense NoninterestExpense	216876000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	46072000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	68881000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	107652000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	156263000	USD
CY2020Q3	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	11199000	USD
CY2019Q3	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	17036000	USD
	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	21126000	USD
	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	38565000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	34873000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	51845000	USD
	us-gaap	Net Income Loss NetIncomeLoss	86526000	USD
	us-gaap	Net Income Loss NetIncomeLoss	117698000	USD
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.06
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.51
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.59
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.65
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.06
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.51
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.59
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.64
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	32951918	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34361176	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	33358879	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	32283196	shares
CY2020Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	24758	shares
CY2019Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	39390	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	27871	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	45416	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	32976676	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34400566	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	33386750	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	32328612	shares
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	34873000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	51845000	USD
	us-gaap	Net Income Loss NetIncomeLoss	86526000	USD
	us-gaap	Net Income Loss NetIncomeLoss	117698000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-709000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	2175000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	10333000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	12349000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-2729000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	3030000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	20452000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	14905000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-225000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-41000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	322000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-121000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3213000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	5246000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	30463000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	27375000	USD
	us-gaap	Off Balance Sheet Credit Loss Liability Change In Method Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityChangeInMethodCreditLossExpenseReversal	-1000000.0	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	31660000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	57091000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	116989000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	145073000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	1671692000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	34873000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3213000	USD
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	15161000	USD
CY2020Q3	indb	Stock Repurchased During Period Valueasaresultof Stock Options Exercised StockRepurchasedDuringPeriodValueasaresultofStockOptionsExercised	140000	USD
CY2020Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	868000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-3000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	528000	USD
CY2020Q3	us-gaap	Increase Decrease In Deferred Compensation IncreaseDecreaseInDeferredCompensation	0	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	1689724000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	1636003000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	51845000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	5246000	USD
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	15125000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	0	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	0	USD
CY2019Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	981000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-4000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	3378000	USD
CY2019Q3	us-gaap	Increase Decrease In Deferred Compensation IncreaseDecreaseInDeferredCompensation	0	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	1682324000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1708143000	USD
	us-gaap	Net Income Loss NetIncomeLoss	86526000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	30463000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	45715000	USD
	indb	Stock Repurchased During Period Valueasaresultof Stock Options Exercised StockRepurchasedDuringPeriodValueasaresultofStockOptionsExercised	114000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3297000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-1186000	USD
	indb	Off Balance Sheet Credit Loss Liability Changein Method Credit Loss Expense Reversalnetoftax. OffBalanceSheetCreditLossLiabilityChangeinMethodCreditLossExpenseReversalnetoftax.	736000	USD
	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	1620000	USD
	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	95091000	USD
	us-gaap	Increase Decrease In Deferred Compensation IncreaseDecreaseInDeferredCompensation	0	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	1689724000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1073490000	USD
	us-gaap	Net Income Loss NetIncomeLoss	117698000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	27375000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	42603000	USD
	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	499693000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	281000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3413000	USD
	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-1435000	USD
	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	4412000	USD
	us-gaap	Increase Decrease In Deferred Compensation IncreaseDecreaseInDeferredCompensation	0	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	1682324000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Effect Of Change In Method FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod	-1100000	USD
CY2020Q3	indb	Financing Receivable Allowancefor Credit Losses Effectof Changein Methodnetoftax. FinancingReceivableAllowanceforCreditLossesEffectofChangeinMethodnetoftax.	817000	USD
	us-gaap	Net Income Loss NetIncomeLoss	86526000	USD
	us-gaap	Net Income Loss NetIncomeLoss	117698000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	21071000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	13919000	USD
	indb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	9406000	USD
	indb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	7262000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	52500000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2000000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2802000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	171000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-107000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	1562000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1462000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-363000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-180000	USD
	us-gaap	Loss On Derivative Instruments Pretax LossOnDerivativeInstrumentsPretax	684000	USD
	us-gaap	Loss On Derivative Instruments Pretax LossOnDerivativeInstrumentsPretax	0	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	389000	USD
	us-gaap	Sale Leaseback Transaction Current Period Gain Recognized SaleLeasebackTransactionCurrentPeriodGainRecognized	433000	USD
	us-gaap	Sale Leaseback Transaction Current Period Gain Recognized SaleLeasebackTransactionCurrentPeriodGainRecognized	433000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	3297000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	3413000	USD
	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	3902000	USD
	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	3572000	USD
	indb	Gain Realized On Life Insurance Policies GainRealizedOnLifeInsurancePolicies	692000	USD
	indb	Gain Realized On Life Insurance Policies GainRealizedOnLifeInsurancePolicies	434000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	8899000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	7798000	USD
	indb	Change In Fair Value On Loans Held For Sale ChangeInFairValueOnLoansHeldForSale	1252000	USD
	indb	Change In Fair Value On Loans Held For Sale ChangeInFairValueOnLoansHeldForSale	1192000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	433000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	459000	USD
	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	20154000	USD
	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	-37672000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	200520000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	57624000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	89164000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	40668000	USD
	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	-75703000	USD
	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	19538000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	10823000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	137236000	USD
	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	0	USD
	us-gaap	Proceeds From Sale Of Trading Securities Heldforinvestment ProceedsFromSaleOfTradingSecuritiesHeldforinvestment	1461000	USD
	us-gaap	Increase Decrease In Equity Securities Fv Ni IncreaseDecreaseInEquitySecuritiesFvNi	331000	USD
	us-gaap	Increase Decrease In Equity Securities Fv Ni IncreaseDecreaseInEquitySecuritiesFvNi	356000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	45863000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	74898000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	35770000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	58704000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	16230000	USD
	us-gaap	Proceeds From Maturities Repayments And Calls Of Trading Securities Heldforinvestment ProceedsFromMaturitiesRepaymentsAndCallsOfTradingSecuritiesHeldforinvestment	176841000	USD
	us-gaap	Proceeds From Maturities Repayments And Calls Of Trading Securities Heldforinvestment ProceedsFromMaturitiesRepaymentsAndCallsOfTradingSecuritiesHeldforinvestment	87313000	USD
	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	95017000	USD
	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	56937000	USD
	us-gaap	Payments For Proceeds From Federal Home Loan Bank Stock PaymentsForProceedsFromFederalHomeLoanBankStock	666000	USD
	us-gaap	Payments For Proceeds From Federal Home Loan Bank Stock PaymentsForProceedsFromFederalHomeLoanBankStock	-18344000	USD
	indb	Investmentin Low Income Housing Projects InvestmentinLowIncomeHousingProjects	-15586000	USD
	indb	Investmentin Low Income Housing Projects InvestmentinLowIncomeHousingProjects	-3549000	USD
	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	116000	USD
	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	115000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2629000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	3162000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	525626000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	11668000	USD
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	105264000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	8283000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11753000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	283000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	17000	USD
	indb	Payments On Early Termination Of Hedging Relationship PaymentsOnEarlyTerminationOfHedgingRelationship	684000	USD
	indb	Payments On Early Termination Of Hedging Relationship PaymentsOnEarlyTerminationOfHedgingRelationship	0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-450362000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-13942000	USD
	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-336289000	USD
	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	28113000	USD
	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	2040615000	USD
	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	-56714000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	55000000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-177046000	USD
	indb	Increase Decrease In Federal Home Loan Bank Advances Long Term IncreaseDecreaseInFederalHomeLoanBankAdvancesLongTerm	-25000000	USD
	indb	Increase Decrease In Federal Home Loan Bank Advances Long Term IncreaseDecreaseInFederalHomeLoanBankAdvancesLongTerm	-25000000	USD
	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	49980000	USD
	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	49980000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	37500000	USD
	us-gaap	Proceeds From Issuance Of Debt ProceedsFromIssuanceOfDebt	74867000	USD
	indb	Repayments Of Junior Subordinated Debt RepaymentsOfJuniorSubordinatedDebt	0	USD
	indb	Repayments Of Junior Subordinated Debt RepaymentsOfJuniorSubordinatedDebt	13329000	USD
	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	49526000	USD
	indb	Net Purchasesfrom Stock Options Exercised NetPurchasesfromStockOptionsExercised	-114000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	281000	USD
	indb	Issuance Of Restricted Stock Awards Netof Issuance Cost IssuanceOfRestrictedStockAwardsNetofIssuanceCost	1186000	USD
	indb	Issuance Of Restricted Stock Awards Netof Issuance Cost IssuanceOfRestrictedStockAwardsNetofIssuanceCost	1435000	USD
	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	1620000	USD
	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	4412000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	95091000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2019Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	2200000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	45681000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	38152000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1556602000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-154477000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	1117063000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-31183000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	150974000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	250455000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	1268037000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	219272000	USD
	indb	Capitalcommitmentrelatingto Low Income Housing Projectinvestmentsnoncash CapitalcommitmentrelatingtoLowIncomeHousingProjectinvestmentsnoncash	28027000	USD
	indb	Capitalcommitmentrelatingto Low Income Housing Projectinvestmentsnoncash CapitalcommitmentrelatingtoLowIncomeHousingProjectinvestmentsnoncash	15740000	USD
CY2019Q1	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	32777000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7693000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7593000	USD
	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	0	USD
	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	499693000	USD
CY2020Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets	0	USD
CY2019Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets	2711067000	USD
CY2020Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	0	USD
CY2019Q3	us-gaap	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	2106110000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	32800000	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	34100000	USD
CY2018Q4	us-gaap	Deferred Rent Credit DeferredRentCredit	1300000	USD
CY2020Q3	us-gaap	Trading Securities Debt TradingSecuritiesDebt	2600000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	21100000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	21300000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	308000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	211000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-107000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	1562000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	0	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	0	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	6000	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	6000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	308000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	211000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-113000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	1556000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	404159000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	19871000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	552000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	423478000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	420703000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	6118000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	397000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	426424000	USD
	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-1500000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	6	holding
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	28137000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	140000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1021000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	412000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	29158000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	552000	USD
CY2020Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	659573000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	30896000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	2000	USD
CY2020Q3	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	690467000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	740806000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	13428000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	971000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	753263000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	404159000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	423478000	USD
CY2020Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	659573000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Datewithin One Year Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDatewithinOneYearAmortizedCost	10026000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Datewithin One Year Fair Value DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDatewithinOneYearFairValue	10109000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Dateafter One Through Five Years Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDateafterOneThroughFiveYearsAmortizedCost	86523000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Dateafter One Through Five Years Fair Value DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDateafterOneThroughFiveYearsFairValue	89073000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Dateafter Five Through Ten Years Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDateafterFiveThroughTenYearsAmortizedCost	106650000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Dateafter Five Through Ten Years Fair Value DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDateafterFiveThroughTenYearsFairValue	113935000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Dateafter Ten Years Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDateafterTenYearsAmortizedCost	860533000	USD
CY2020Q3	indb	Debt Securities Availableforsaleand Heldtomaturity Maturity Allocatedand Single Maturity Dateafter Ten Years Fair Value DebtSecuritiesAvailableforsaleandHeldtomaturityMaturityAllocatedandSingleMaturityDateafterTenYearsFairValue	900828000	USD
CY2020Q3	indb	Available For Sale Securities And Held To Maturity Securities Amortized Cost AvailableForSaleSecuritiesAndHeldToMaturitySecuritiesAmortizedCost	1063732000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	1113945000	USD
CY2020Q3	indb	Callable Securities In Investment Portfolio CallableSecuritiesInInvestmentPortfolio	3900000	USD
CY2020Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	417100000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	375500000	USD
CY2019Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	0	USD
CY2020Q3	indb	Investmentsinobligationsofindividualstatescountiesormunicipalitieswhichexceed10ofequity Investmentsinobligationsofindividualstatescountiesormunicipalitieswhichexceed10ofequity	0	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	0	USD
	indb	Days To Be Termed As Non Accrual Loans DaysToBeTermedAsNonAccrualLoans	P90D
	indb	Days To Be Termed As Non Accrual Loans DaysToBeTermedAsNonAccrualLoans	P90D
	indb	Days To Be Termed As Non Accrual Loans DaysToBeTermedAsNonAccrualLoans	P90D
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	112176000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	4304000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	253000	USD
CY2020Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	7500000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	115625000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	67740000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Effect Of Change In Method FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod	-1137000	USD
	us-gaap	Financing Receivable Allowance For Credit Loss Purchased With Credit Deterioration Increase FinancingReceivableAllowanceForCreditLossPurchasedWithCreditDeteriorationIncrease	1157000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	5748000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1113000	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	52500000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	115625000	USD
CY2020Q3	us-gaap	Interest Receivable InterestReceivable	36700000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Effect Of Change In Method FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod	-1100000	USD
	us-gaap	Financing Receivable Allowance For Credit Loss Purchased With Credit Deterioration Increase FinancingReceivableAllowanceForCreditLossPurchasedWithCreditDeteriorationIncrease	1200000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	115600000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	-47900000	USD
	indb	Financing Receivable Allowancefor Credit Loss Period Increase Decreasebypercentage FinancingReceivableAllowanceforCreditLossPeriodIncreaseDecreasebypercentage	0.706
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	-3400000	USD
CY2020Q3	indb	Financing Receivable Allowancefor Credit Loss Period Increase Decreasebypercentage FinancingReceivableAllowanceforCreditLossPeriodIncreaseDecreasebypercentage	0.031
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	7500000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25000000.0	USD
CY2020Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	20000000.0	USD
CY2020Q3	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	2199885000	USD
CY2020Q3	us-gaap	Financing Receivable Originated In Fiscal Year Before Latest Fiscal Year FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear	1504307000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	1047533000	USD
CY2020Q3	indb	Tdrs Recorded Investment On Nonaccrual Status TdrsRecordedInvestmentOnNonaccrualStatus	23800000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	970908000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	758331000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	1445238000	USD
CY2020Q3	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	1454822000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	9405193000	USD
CY2020Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1000000.0	USD
	indb	Days To Be Termed As Non Accrual Loans DaysToBeTermedAsNonAccrualLoans	P90D
	indb	Days To Be Termed As Non Accrual Loans DaysToBeTermedAsNonAccrualLoans	P90D
CY2020Q3	indb	Loanswithactive Deferrals LoanswithactiveDeferrals	583800000	USD
CY2019Q4	indb	Tdrs Recorded Investment On Nonaccrual Status TdrsRecordedInvestmentOnNonaccrualStatus	24800000	USD
CY2020Q3	indb	Finance Receivable Nonaccrualwithallowance FinanceReceivableNonaccrualwithallowance	55369000	USD
CY2020Q3	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	42655000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	98024000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	45892000	USD
CY2020Q3	indb	Foreclosedresidentialrealestatepropertyheldbythecreditor Foreclosedresidentialrealestatepropertyheldbythecreditor	0	USD
CY2019Q4	indb	Foreclosedresidentialrealestatepropertyheldbythecreditor Foreclosedresidentialrealestatepropertyheldbythecreditor	0	USD
CY2020Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	2113000	USD
CY2019Q4	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	3294000	USD
CY2020Q3	indb	Number Of Financing Receivables Thirty To Fifty Nine Days Past Due NumberOfFinancingReceivablesThirtyToFiftyNineDaysPastDue	274	loan
CY2020Q3	indb	Number Of Financing Receivables Sixty To Eighty Nine Days Past Due NumberOfFinancingReceivablesSixtyToEightyNineDaysPastDue	30	loan
CY2020Q3	indb	Number Of Financing Receivables Equal To Greater Than Ninety Days NumberOfFinancingReceivablesEqualToGreaterThanNinetyDays	107	loan
CY2020Q3	indb	Number Of Financing Receivables Total Past Due NumberOfFinancingReceivablesTotalPastDue	411	loan
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	29589000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	9375604000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	9405193000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	1000	USD
CY2019Q4	indb	Number Of Financing Receivables Thirty To Fifty Nine Days Past Due NumberOfFinancingReceivablesThirtyToFiftyNineDaysPastDue	447	loan
CY2019Q4	indb	Number Of Financing Receivables Sixty To Eighty Nine Days Past Due NumberOfFinancingReceivablesSixtyToEightyNineDaysPastDue	43	loan
CY2019Q4	indb	Number Of Financing Receivables Equal To Greater Than Ninety Days NumberOfFinancingReceivablesEqualToGreaterThanNinetyDays	113	loan
CY2019Q4	indb	Number Of Financing Receivables Total Past Due NumberOfFinancingReceivablesTotalPastDue	603	loan
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	25485000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	8848154000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	8873639000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	2157000	USD
CY2020Q3	indb	Tdrs Recorded Investment On Accrual Status TdrsRecordedInvestmentOnAccrualStatus	17521000	USD
CY2019Q4	indb	Tdrs Recorded Investment On Accrual Status TdrsRecordedInvestmentOnAccrualStatus	19599000	USD
CY2020Q3	indb	Tdrs Recorded Investment On Nonaccrual Status TdrsRecordedInvestmentOnNonaccrualStatus	23810000	USD
CY2019Q4	indb	Tdrs Recorded Investment On Nonaccrual Status TdrsRecordedInvestmentOnNonaccrualStatus	24766000	USD
CY2020Q3	indb	Financing Receivable Recorded Investment Trouble Debt Restructuring FinancingReceivableRecordedInvestmentTroubleDebtRestructuring	41331000	USD
CY2019Q4	indb	Financing Receivable Recorded Investment Trouble Debt Restructuring FinancingReceivableRecordedInvestmentTroubleDebtRestructuring	44365000	USD
CY2019Q4	indb	Amount Of Specific Reserves Included In Allowance For Loan Losses Associated With Trouble Debt Restructuring AmountOfSpecificReservesIncludedInAllowanceForLoanLossesAssociatedWithTroubleDebtRestructuring	855000	USD
CY2020Q3	indb	Additional Commitments To Lend To Borrower For Trouble Debt Restructuring AdditionalCommitmentsToLendToBorrowerForTroubleDebtRestructuring	158000	USD
CY2019Q4	indb	Additional Commitments To Lend To Borrower For Trouble Debt Restructuring AdditionalCommitmentsToLendToBorrowerForTroubleDebtRestructuring	63000	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5	contract
CY2020Q3	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	827000	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	827000	USD
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	17	contract
	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	3580000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	3639000	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5	contract
CY2019Q3	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	448000	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	453000	USD
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	9	contract
	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	784000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	789000	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	827000	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	453000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	3639000	USD
	us-gaap	Financing Receivable Troubled Debt Restructuring Increase Decrease From Modification FinancingReceivableTroubledDebtRestructuringIncreaseDecreaseFromModification	831000	USD
	indb	Days To Be Termed As Non Accrual Loans DaysToBeTermedAsNonAccrualLoans	P90D
CY2020Q3	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	8809155000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	49628000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	8873639000	USD
CY2019Q4	indb	Unamortized Loan Commitmentand Originationfees UnamortizedLoanCommitmentandOriginationfees	7100000	USD
CY2019Q4	indb	Unamortized Discountsor Premiums UnamortizedDiscountsorPremiums	21600000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	2100000	USD
CY2019Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	65960000	USD
CY2019Q3	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	-707000	USD
CY2019Q3	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	1689000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	66942000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	64293000	USD
	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1738000	USD
	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	2387000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2000000	USD
CY2019Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	66942000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	66105000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	837000	USD
CY2019Q4	us-gaap	Notes Receivable Net NotesReceivableNet	6119185000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	980000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	49628000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	68140000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	980000	USD
CY2019Q3	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	57363000	USD
CY2019Q3	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	392000	USD
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	60120000	USD
	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	1214000	USD
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Outstanding Balance CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesOutstandingBalance	18358000	USD
CY2019Q2	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYield	2238000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYield	1191000	USD
CY2020Q3	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldAdditions	0	USD
	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldAdditions	1464000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	412000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	1215000	USD
CY2019Q3	indb	Certainloansacquiredinatransfernotaccountedforasdebtsecuritiesaccretableyieldadjustmentchangesinexpectedcashflow Certainloansacquiredinatransfernotaccountedforasdebtsecuritiesaccretableyieldadjustmentchangesinexpectedcashflow	237000	USD
	indb	Certainloansacquiredinatransfernotaccountedforasdebtsecuritiesaccretableyieldadjustmentchangesinexpectedcashflow Certainloansacquiredinatransfernotaccountedforasdebtsecuritiesaccretableyieldadjustmentchangesinexpectedcashflow	623000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	227000	USD
	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	227000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYield	2290000	USD
CY2019Q3	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYield	2290000	USD
CY2020Q3	us-gaap	Goodwill Goodwill	506206000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	506206000	USD
CY2020Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	24543000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	29286000	USD
CY2020Q3	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	530749000	USD
CY2019Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	535492000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	34873000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	51845000	USD
	us-gaap	Net Income Loss NetIncomeLoss	86526000	USD
	us-gaap	Net Income Loss NetIncomeLoss	117698000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	32951918	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34361176	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	33358879	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	32283196	shares
CY2020Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	24758	shares
CY2019Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	39390	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	27871	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	45416	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	32976676	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34400566	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	33386750	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	32328612	shares
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.06
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.51
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.59
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.65
CY2020Q3	indb	Effect Of Dilutive Shares EffectOfDilutiveShares	0
CY2019Q3	indb	Effect Of Dilutive Shares EffectOfDilutiveShares	0
	indb	Effect Of Dilutive Shares EffectOfDilutiveShares	0
	indb	Effect Of Dilutive Shares EffectOfDilutiveShares	-0.01
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.06
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.51
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.59
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.64
	us-gaap	Maximum Length Of Time Hedged In Interest Rate Cash Flow Hedge1 MaximumLengthOfTimeHedgedInInterestRateCashFlowHedge1	P4Y1M6D
CY2020Q3	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	-684000	USD
CY2020Q3	us-gaap	Fair Value Hedges At Fair Value Net FairValueHedgesAtFairValueNet	0	USD
CY2020Q3	indb	Change In Fair Value On Loans Held For Sale ChangeInFairValueOnLoansHeldForSale	413000	USD
CY2019Q3	indb	Change In Fair Value On Loans Held For Sale ChangeInFairValueOnLoansHeldForSale	272000	USD
	indb	Change In Fair Value On Loans Held For Sale ChangeInFairValueOnLoansHeldForSale	1300000	USD
	indb	Change In Fair Value On Loans Held For Sale ChangeInFairValueOnLoansHeldForSale	1200000	USD
CY2020Q3	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	10000000.0	USD
CY2019Q3	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	5500000	USD
	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	20700000	USD
	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	9500000	USD
CY2020Q3	us-gaap	Derivative Assets DerivativeAssets	210754000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	78385000	USD
CY2020Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	132625000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	53923000	USD
CY2020Q3	us-gaap	Derivative Collateral Obligation To Return Securities DerivativeCollateralObligationToReturnSecurities	54047000	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Securities DerivativeCollateralObligationToReturnSecurities	24882000	USD
CY2020Q3	us-gaap	Derivative Collateral Right To Reclaim Securities DerivativeCollateralRightToReclaimSecurities	54047000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Securities DerivativeCollateralRightToReclaimSecurities	24882000	USD
CY2020Q3	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	0	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	0	USD
CY2020Q3	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	73094000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	25493000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	156707000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	53503000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	5484000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	3548000	USD
CY2020Q3	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	-684000	USD
CY2019Q3	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	0	USD
	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	-684000	USD
	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	0	USD
CY2020Q3	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	93000000.0	USD
CY2019Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	26000000.0	USD
CY2020Q3	indb	Exposureto Institutional Counterparties ExposuretoInstitutionalCounterparties	54000000.0	USD
CY2019Q4	indb	Exposureto Institutional Counterparties ExposuretoInstitutionalCounterparties	25400000	USD
CY2020Q3	indb	Exposure To Counterparties Relating To Customer Related Positions ExposureToCounterpartiesRelatingToCustomerRelatedPositions	145500000	USD
CY2019Q4	indb	Exposure To Counterparties Relating To Customer Related Positions ExposureToCounterpartiesRelatingToCustomerRelatedPositions	51000000.0	USD
CY2020Q3	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	11199000	USD
CY2019Q3	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	17036000	USD
	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	21126000	USD
	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	38565000	USD
CY2020Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2431
CY2019Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2473
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.1962
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2468
CY2020Q3	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	11200000	USD
CY2019Q3	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	17000000.0	USD
	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	21100000	USD
	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	38600000	USD
CY2020Q3	us-gaap	Long Term Debt LongTermDebt	37447000	USD
CY2020Q3	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	36448000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	74906000	USD
CY2019Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	72219000	USD
CY2020Q3	indb	Othernoninterestincome Asc606 OthernoninterestincomeASC606	905000	USD
CY2019Q3	indb	Othernoninterestincome Asc606 OthernoninterestincomeASC606	1487000	USD
	indb	Othernoninterestincome Asc606 OthernoninterestincomeASC606	2651000	USD
	indb	Othernoninterestincome Asc606 OthernoninterestincomeASC606	4068000	USD
	indb	Totalnoninterestincomeinscopeof Asc606 TotalnoninterestincomeinscopeofASC606	49661000	USD
	indb	Totalnoninterestincomeinscopeof Asc606 TotalnoninterestincomeinscopeofASC606	56710000	USD
CY2020Q3	indb	Totalnoninterestincomeinscopeof Asc606 TotalnoninterestincomeinscopeofASC606	15183000	USD
CY2019Q3	indb	Totalnoninterestincomeinscopeof Asc606 TotalnoninterestincomeinscopeofASC606	20056000	USD
CY2020Q3	indb	Totalnoninterestincomeoutofscopeof Asc606 TotalnoninterestincomeoutofscopeofASC606	14164000	USD
CY2019Q3	indb	Totalnoninterestincomeoutofscopeof Asc606 TotalnoninterestincomeoutofscopeofASC606	11760000	USD
	indb	Totalnoninterestincomeoutofscopeof Asc606 TotalnoninterestincomeoutofscopeofASC606	34311000	USD
	indb	Totalnoninterestincomeoutofscopeof Asc606 TotalnoninterestincomeoutofscopeofASC606	25287000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	29347000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	31816000	USD
	us-gaap	Noninterest Income NoninterestIncome	83972000	USD
	us-gaap	Noninterest Income NoninterestIncome	81997000	USD
CY2020Q3	indb	Investment Management Income Receivable InvestmentManagementIncomeReceivable	4383000	USD
CY2019Q4	indb	Investment Management Income Receivable InvestmentManagementIncomeReceivable	2341000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-709000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-857000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-148000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	13598000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	3265000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	10333000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	-857000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	-148000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-709000	USD
	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	13598000	USD
	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	3265000	USD
	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	10333000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-143000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-41000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-102000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	37674000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	10597000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	27077000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	4339000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	1220000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	3119000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	9901000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	2784000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	7117000	USD
CY2020Q3	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	-684000	USD
CY2020Q3	indb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Loss On Termination Of Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForLossOnTerminationOfDerivativesTax	-192000	USD
CY2020Q3	indb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Loss On Termination Of Derivatives After Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForLossOnTerminationOfDerivativesAfterTax	-492000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	-1069000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-176000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-736000	USD
	indb	Other Comprehensive Income Loss Reclassification Adjustmentfrom Aoc Ifor Losson Terminationof Derivativesbefore Tax OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIforLossonTerminationofDerivativesbeforeTax	-684000	USD
	indb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Loss On Termination Of Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForLossOnTerminationOfDerivativesTax	-192000	USD
	indb	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Loss On Termination Of Derivatives After Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForLossOnTerminationOfDerivativesAfterTax	-492000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	-3798000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-2729000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	28457000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	8005000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	20452000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-2000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-1000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-1000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-1392000	USD
	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-392000	USD
	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-1000000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-245000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-69000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-207000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-529000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	69000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	19000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	50000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	207000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	58000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	149000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-312000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-87000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-225000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	449000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	127000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	322000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-4343000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-1130000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-3213000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	41606000	USD
	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	11143000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	30463000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	2858000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	683000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	2175000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	14699000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	3401000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	11298000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-1462000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-411000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-1051000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	2858000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	683000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	1285000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	2175000	USD
	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Before Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent	16161000	USD
	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	3812000	USD
	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	12349000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	4568000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	3283000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	21913000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	6167000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	15746000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	352000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	99000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	253000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	1170000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	329000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	841000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	4216000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	1186000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	3030000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	20743000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	5838000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	14905000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-11000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-3000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-8000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-33000	USD
	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-9000	USD
	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-24000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	2000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	1000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	1000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	6000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	2000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	4000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	69000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	19000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	50000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	207000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	58000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	149000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-56000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-15000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-41000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-168000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-47000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-121000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	7130000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	1884000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	5246000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	37072000	USD
	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	9697000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	27375000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	18169000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	30463000	USD
CY2020Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	48632000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1173000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	27375000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	26202000	USD
CY2020Q3	us-gaap	Cash Reserve Deposit Required And Made CashReserveDepositRequiredAndMade	0	USD
CY2019Q4	us-gaap	Cash Reserve Deposit Required And Made CashReserveDepositRequiredAndMade	0	USD
CY2020Q3	indb	Original Investmentin Low Income Housing Projects OriginalInvestmentinLowIncomeHousingProjects	124302000	USD
CY2019Q4	indb	Original Investmentin Low Income Housing Projects OriginalInvestmentinLowIncomeHousingProjects	96275000	USD
CY2020Q3	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	94097000	USD
CY2019Q4	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	72510000	USD
CY2020Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	47408000	USD
CY2019Q4	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	34967000	USD
	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	10671000	USD
CY2019	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	7342000	USD
	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	8676000	USD
CY2019	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	5645000	USD
	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	1995000	USD
CY2019	us-gaap	Income Loss From Affordable Housing Projects Equity Method Investments IncomeLossFromAffordableHousingProjectsEquityMethodInvestments	1696000	USD
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2000000.0	USD

Files In Submission

Name	View Source	Status
0000776901-20-000175-index-headers.html	Edgar Link	pending
0000776901-20-000175-index.html	Edgar Link	pending
0000776901-20-000175.txt	Edgar Link	pending
0000776901-20-000175-xbrl.zip	Edgar Link	pending
exhibit311-indb09x30x2.htm	Edgar Link	pending
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exhibit321-indb09x30x2.htm	Edgar Link	pending
exhibit322-indb09x30x2.htm	Edgar Link	pending
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Financial_Report.xlsx	Edgar Link	pending
indb-20200930.htm	Edgar Link	pending
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indb-20200930_htm.xml	Edgar Link	completed
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$INDB
INDEPENDENT BANK CORP Stock $indb

2020 Q3 Form 10-Q Financial Statement

#000077690120000175 Filed on November 05, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$INDB INDEPENDENT BANK CORP Stock $indb

2020 Q3 Form 10-Q Financial Statement

#000077690120000175 Filed on November 05, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$INDB
INDEPENDENT BANK CORP Stock $indb