$EBC
Eastern Bankshares, Inc. Stock $ebc

$ebc Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000162828023005001 Filed on February 24, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$49.20M		$176.6M
YoY Change	-62.58%		-59.42%
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	$3.719M	$3.936M	$14.96M
YoY Change	-2.21%	-14.43%	3.3%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$50.57M		$37.13M
YoY Change	1404.64%		596.31%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	-$256.3M	$50.87M	$256.7M
YoY Change	-487.47%	57.99%	36.02%
Income Tax	-$62.24M	$8.579M	$56.93M
% Of Pretax Income		16.86%	22.18%
Net Earnings	-$194.1M	$42.29M	$199.8M
YoY Change	-476.77%	20.5%	29.16%
Net Earnings / Revenue	-394.49%		113.12%
Basic Earnings Per Share	-$1.20		$1.21
Diluted Earnings Per Share	-$1.20	$260.7K	$1.206M
COMMON SHARES
Basic Shares Outstanding	176.2M shares	176.7M shares	165.5M shares
Diluted Shares Outstanding	162.1M shares		165.6M shares

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$2.138B	$169.5M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$61.11M	$62.66M	$62.66M
YoY Change	-16.49%	-22.63%	-62.03%
Goodwill	$640.2M	$640.2M
YoY Change	0.86%	1.38%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$314.1M	$331.6M	$331.6M
YoY Change	71.53%	330.71%	330.71%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$22.72B	$22.65B	$22.65B
YoY Change	-0.51%	-3.68%	-3.68%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$59.46M	$61.21M	$61.21M
YoY Change	-30.52%	-31.23%	-31.23%
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$59.46M	$61.21M	$61.21M
YoY Change	-30.52%	-31.23%	-31.23%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$413.7M	$474.3M	$474.3M
YoY Change	31.61%	33.99%	33.99%
Total Long-Term Liabilities	$413.7M	$474.3M	$474.3M
YoY Change	31.61%	33.99%	33.99%
TOTAL LIABILITIES
Total Short-Term Liabilities	$59.46M	$61.21M	$61.21M
Total Long-Term Liabilities	$413.7M	$474.3M	$474.3M
Total Liabilities	$20.14B	$20.18B	$20.18B
YoY Change	1.58%	0.34%	0.34%
SHAREHOLDERS EQUITY
Retained Earnings	$1.672B	$1.882B
YoY Change	-6.22%	6.4%
Common Stock	$1.764M	$1.762M
YoY Change	-3.82%	-5.42%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.579B	$2.472B	$2.472B
YoY Change
Total Liabilities & Shareholders Equity	$22.72B	$22.65B	$22.65B
YoY Change	-0.51%	-3.68%	-3.68%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	-$194.1M	$42.29M	$199.8M
YoY Change	-476.77%	20.5%	29.16%
Depreciation, Depletion And Amortization	$3.719M	$3.936M	$14.96M
YoY Change	-2.21%	-14.43%	3.3%
Cash From Operating Activities	$100.5M	$3.438M	$229.9M
YoY Change	47.01%	-92.75%	31.78%
INVESTING ACTIVITIES
Capital Expenditures	$1.217M	$2.246M	$8.627M
YoY Change	-137.1%	-218.21%	-251.35%
Acquisitions	$0.00		$13.40M
YoY Change	-100.0%		-0.29%
Other Investing Activities	$1.921B	-$502.0M	-$1.068B
YoY Change	-1347.43%	-224.31%	-46.06%
Cash From Investing Activities	$1.920B	-$504.2M	-$1.077B
YoY Change	-1320.63%	-225.45%	-45.78%
FINANCING ACTIVITIES
Cash Dividend Paid	$16.20M	$16.10M	$65.89M
YoY Change	-4.14%	17.52%	27.78%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$51.77M	511.8M	-$215.6M
YoY Change	-83.43%	-209.11%	-121.8%
NET CHANGE
Cash From Operating Activities	$100.5M	3.438M	$229.9M
Cash From Investing Activities	$1.920B	-504.2M	-$1.077B
Cash From Financing Activities	-$51.77M	511.8M	-$215.6M
Net Change In Cash	$1.968B	11.07M	-$1.062B
YoY Change	-590.49%	-155.9%	29.19%
FREE CASH FLOW
Cash From Operating Activities	$100.5M	$3.438M	$229.9M
Capital Expenditures	$1.217M	$2.246M	$8.627M
Free Cash Flow	$99.30M	$1.192M	$221.3M
YoY Change	38.58%	-97.58%	22.82%

Facts In Submission

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CY2022	dei	Document Type DocumentType	10-K
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CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022	dei	Document Transition Report DocumentTransitionReport	false
CY2022	dei	Entity File Number EntityFileNumber	001-39610
CY2022	dei	Entity Registrant Name EntityRegistrantName	Eastern Bankshares, Inc.
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MA
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	84-4199750
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	265 Franklin Street
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	Boston
CY2022	dei	Entity Address State Or Province EntityAddressStateOrProvince	MA
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	02110
CY2022	dei	City Area Code CityAreaCode	800
CY2022	dei	Local Phone Number LocalPhoneNumber	327-8376
CY2022	dei	Security12b Title Security12bTitle	Common Stock
CY2022	dei	Trading Symbol TradingSymbol	EBC
CY2022	dei	Security Exchange Name SecurityExchangeName	NASDAQ
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CY2022Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1649141000	usd
CY2021Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1835241000	usd
CY2022Q4	us-gaap	Unearned Esop Shares UnearnedESOPShares	137696000	usd
CY2021Q4	us-gaap	Unearned Esop Shares UnearnedESOPShares	142709000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1881775000	usd
CY2021Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1768653000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-923192000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-56696000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	2471790000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	3406352000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	22646858000	usd
CY2021Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	23512128000	usd
CY2022	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	476041000	usd
CY2021	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	367585000	usd
CY2020	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	372152000	usd
CY2022	ebc	Taxable Interest And Dividends On Available For Sale Securities TaxableInterestAndDividendsOnAvailableForSaleSecurities	118690000	usd
CY2021	ebc	Taxable Interest And Dividends On Available For Sale Securities TaxableInterestAndDividendsOnAvailableForSaleSecurities	58312000	usd
CY2020	ebc	Taxable Interest And Dividends On Available For Sale Securities TaxableInterestAndDividendsOnAvailableForSaleSecurities	31825000	usd
CY2022	ebc	Nontaxable Interest And Dividends On Available For Sale Securities NontaxableInterestAndDividendsOnAvailableForSaleSecurities	7179000	usd
CY2021	ebc	Nontaxable Interest And Dividends On Available For Sale Securities NontaxableInterestAndDividendsOnAvailableForSaleSecurities	7376000	usd
CY2020	ebc	Nontaxable Interest And Dividends On Available For Sale Securities NontaxableInterestAndDividendsOnAvailableForSaleSecurities	7588000	usd
CY2022	ebc	Interest On Federal Funds Sold And Other Short Term Investments InterestOnFederalFundsSoldAndOtherShortTermInvestments	3271000	usd
CY2021	ebc	Interest On Federal Funds Sold And Other Short Term Investments InterestOnFederalFundsSoldAndOtherShortTermInvestments	1886000	usd
CY2020	ebc	Interest On Federal Funds Sold And Other Short Term Investments InterestOnFederalFundsSoldAndOtherShortTermInvestments	1757000	usd
CY2022	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	0	usd
CY2021	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	0	usd
CY2020	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	6000	usd
CY2022	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	605181000	usd
CY2021	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	435159000	usd
CY2020	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	413328000	usd
CY2022	us-gaap	Interest Expense Deposits InterestExpenseDeposits	28621000	usd
CY2021	us-gaap	Interest Expense Deposits InterestExpenseDeposits	5167000	usd
CY2020	us-gaap	Interest Expense Deposits InterestExpenseDeposits	11315000	usd
CY2022	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	8506000	usd
CY2021	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	165000	usd
CY2020	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	762000	usd
CY2022	us-gaap	Interest Expense InterestExpense	37127000	usd
CY2021	us-gaap	Interest Expense InterestExpense	5332000	usd
CY2020	us-gaap	Interest Expense InterestExpense	12077000	usd
CY2022	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	568054000	usd
CY2021	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	429827000	usd
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	401251000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	17925000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	-9686000	usd
CY2020	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	38800000	usd
CY2022	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	550129000	usd
CY2021	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	439513000	usd
CY2020	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	362451000	usd
CY2022	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	99232000	usd
CY2021	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	94704000	usd
CY2020	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	94495000	usd
CY2022	ebc	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	30392000	usd
CY2021	ebc	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	24271000	usd
CY2020	ebc	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	21560000	usd
CY2022	ebc	Trust And Investment Advisory Fees TrustAndInvestmentAdvisoryFees	23593000	usd
CY2021	ebc	Trust And Investment Advisory Fees TrustAndInvestmentAdvisoryFees	24588000	usd
CY2020	ebc	Trust And Investment Advisory Fees TrustAndInvestmentAdvisoryFees	21102000	usd
CY2022	ebc	Debit Card Processing Fees DebitCardProcessingFees	12644000	usd
CY2021	ebc	Debit Card Processing Fees DebitCardProcessingFees	12118000	usd
CY2020	ebc	Debit Card Processing Fees DebitCardProcessingFees	10277000	usd
CY2022	ebc	Interest Rate Swap Income Losses InterestRateSwapIncomeLosses	6009000	usd
CY2021	ebc	Interest Rate Swap Income Losses InterestRateSwapIncomeLosses	5634000	usd
CY2020	ebc	Interest Rate Swap Income Losses InterestRateSwapIncomeLosses	-1381000	usd
CY2022	ebc	Income From Investments Held In Rabbi Trusts IncomeFromInvestmentsHeldInRabbiTrusts	-10762000	usd
CY2021	ebc	Income From Investments Held In Rabbi Trusts IncomeFromInvestmentsHeldInRabbiTrusts	10217000	usd
CY2020	ebc	Income From Investments Held In Rabbi Trusts IncomeFromInvestmentsHeldInRabbiTrusts	10337000	usd
CY2022	us-gaap	Trading Gains Losses TradingGainsLosses	0	usd
CY2021	us-gaap	Trading Gains Losses TradingGainsLosses	0	usd
CY2020	us-gaap	Trading Gains Losses TradingGainsLosses	-4000	usd
CY2022	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	248000	usd
CY2021	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	3605000	usd
CY2020	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	7066000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-3157000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	1166000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	288000	usd
CY2022	us-gaap	Noninterest Income Other NoninterestIncomeOther	17962000	usd
CY2021	us-gaap	Noninterest Income Other NoninterestIncomeOther	16852000	usd
CY2020	us-gaap	Noninterest Income Other NoninterestIncomeOther	14633000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	176161000	usd
CY2021	us-gaap	Noninterest Income NoninterestIncome	193155000	usd
CY2020	us-gaap	Noninterest Income NoninterestIncome	178373000	usd
CY2022	us-gaap	Labor And Related Expense LaborAndRelatedExpense	298186000	usd
CY2021	us-gaap	Labor And Related Expense LaborAndRelatedExpense	295916000	usd
CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	261827000	usd
CY2022	us-gaap	Occupancy Net OccupancyNet	40764000	usd
CY2021	us-gaap	Occupancy Net OccupancyNet	40465000	usd
CY2020	us-gaap	Occupancy Net OccupancyNet	33796000	usd
CY2022	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	57273000	usd
CY2021	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	50839000	usd
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	45259000	usd
CY2022	us-gaap	Professional Fees ProfessionalFees	16814000	usd
CY2021	us-gaap	Professional Fees ProfessionalFees	21879000	usd
CY2020	us-gaap	Professional Fees ProfessionalFees	16445000	usd
CY2022	ebc	Charitable Contributions CharitableContributions	0	usd
CY2021	ebc	Charitable Contributions CharitableContributions	0	usd
CY2020	ebc	Charitable Contributions CharitableContributions	95272000	usd
CY2022	us-gaap	Marketing Expense MarketingExpense	9540000	usd
CY2021	us-gaap	Marketing Expense MarketingExpense	8741000	usd
CY2020	us-gaap	Marketing Expense MarketingExpense	8879000	usd
CY2022	us-gaap	Loan Processing Fee LoanProcessingFee	6384000	usd
CY2021	us-gaap	Loan Processing Fee LoanProcessingFee	9114000	usd
CY2020	us-gaap	Loan Processing Fee LoanProcessingFee	9184000	usd
CY2022	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	6250000	usd
CY2021	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	4226000	usd
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3734000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3864000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2512000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2857000	usd
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	30527000	usd
CY2021	us-gaap	Other Noninterest Expense OtherNoninterestExpense	10264000	usd
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	27670000	usd
CY2022	us-gaap	Noninterest Expense NoninterestExpense	469602000	usd
CY2021	us-gaap	Noninterest Expense NoninterestExpense	443956000	usd
CY2020	us-gaap	Noninterest Expense NoninterestExpense	504923000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	256688000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	188712000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	35901000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56929000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34047000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13163000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	199759000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	154665000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	22738000	usd
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.21
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.90
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.13
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.21
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.90
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.13
CY2022	us-gaap	Net Income Loss NetIncomeLoss	199759000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	154665000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	22738000	usd
CY2022	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-821570000	usd
CY2021	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-104258000	usd
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	23874000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-57520000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-22454000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	14191000	usd
CY2022	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-12594000	usd
CY2021	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-15782000	usd
CY2020	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-60016000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-866496000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-110930000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	98081000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-666737000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	43735000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	120819000	usd
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1600153000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	22738000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	98081000	usd
CY2020	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	28900000	usd
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	1763980000	usd
CY2020	ebc	Stock Issued During Period Value Charitable Donations StockIssuedDuringPeriodValueCharitableDonations	91287000	usd
CY2020	ebc	Stock Purchased During Period Shares Employee Stock Ownership Plan Esop StockPurchasedDuringPeriodSharesEmployeeStockOwnershipPlanESOP	14940652	shares
CY2020	ebc	Stock Purchased During Period Value Employee Stock Ownership Plan Esop StockPurchasedDuringPeriodValueEmployeeStockOwnershipPlanESOP	149407000	usd
CY2020	ebc	Employee Stock Ownership Plan Esop Value Committed To Be Released Shares EmployeeStockOwnershipPlanESOPValueCommittedToBeReleasedShares	2351000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	3428052000	usd
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	51619000	usd
CY2021	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	23224000	usd
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	154665000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-110930000	usd
CY2021	ebc	Employee Stock Ownership Plan Esop Value Committed To Be Released Shares EmployeeStockOwnershipPlanESOPValueCommittedToBeReleasedShares	9408000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	3406352000	usd
CY2022	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	66539000	usd
CY2022	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	201618000	usd
CY2022	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	usd
CY2022	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	usd
CY2022	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	10507000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	199759000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-866496000	usd
CY2022	ebc	Employee Stock Ownership Plan Esop Value Committed To Be Released Shares EmployeeStockOwnershipPlanESOPValueCommittedToBeReleasedShares	9923000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	2471790000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	199759000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	154665000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	22738000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	17925000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	-9686000	usd
CY2020	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	38800000	usd
CY2022	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	14957000	usd
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	14479000	usd
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	15827000	usd
CY2022	ebc	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-1441000	usd
CY2021	ebc	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-27991000	usd
CY2020	ebc	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-14574000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	6023000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5313000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-20359000	usd
CY2022	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	18274000	usd
CY2021	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	16713000	usd
CY2020	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	5585000	usd
CY2022	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	13016000	usd
CY2021	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	12703000	usd
CY2020	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	12082000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	10507000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	0	usd
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	0	usd
CY2022	us-gaap	Increase Decrease In Insurance Settlements Receivable IncreaseDecreaseInInsuranceSettlementsReceivable	3699000	usd
CY2021	us-gaap	Increase Decrease In Insurance Settlements Receivable IncreaseDecreaseInInsuranceSettlementsReceivable	2348000	usd
CY2020	us-gaap	Increase Decrease In Insurance Settlements Receivable IncreaseDecreaseInInsuranceSettlementsReceivable	2188000	usd
CY2022	ebc	Bank Owned Life Insurance Income Expense BankOwnedLifeInsuranceIncomeExpense	-663000	usd
CY2021	ebc	Bank Owned Life Insurance Income Expense BankOwnedLifeInsuranceIncomeExpense	1813000	usd
CY2020	ebc	Bank Owned Life Insurance Income Expense BankOwnedLifeInsuranceIncomeExpense	174000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-3157000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	1166000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	288000	usd
CY2022	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	1412000	usd
CY2021	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-4715000	usd
CY2020	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-73000	usd
CY2022	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	-593000	usd
CY2021	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	-2182000	usd
CY2020	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	0	usd
CY2022	us-gaap	Amortization Of Deferred Hedge Gains AmortizationOfDeferredHedgeGains	-10193000	usd
CY2021	us-gaap	Amortization Of Deferred Hedge Gains AmortizationOfDeferredHedgeGains	-31234000	usd
CY2020	us-gaap	Amortization Of Deferred Hedge Gains AmortizationOfDeferredHedgeGains	-15889000	usd
CY2022	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	9923000	usd
CY2021	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	9408000	usd
CY2020	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	2351000	usd
CY2022	ebc	Issuance Of Common Stock For Charitable Donations IssuanceOfCommonStockForCharitableDonations	0	usd
CY2021	ebc	Issuance Of Common Stock For Charitable Donations IssuanceOfCommonStockForCharitableDonations	0	usd
CY2020	ebc	Issuance Of Common Stock For Charitable Donations IssuanceOfCommonStockForCharitableDonations	91287000	usd
CY2022	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	17000	usd
CY2021	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-526000	usd
CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	-587000	usd
CY2022	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	0	usd
CY2021	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	0	usd
CY2020	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-961000	usd
CY2022	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	3354000	usd
CY2021	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	47000	usd
CY2020	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	1133000	usd
CY2022	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-4338000	usd
CY2021	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-1130000	usd
CY2020	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	24055000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-823000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-61501000	usd
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	89590000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-49934000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-22882000	usd
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	48984000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	229942000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	174490000	usd
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	69851000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	431193000	usd
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	23798000	usd
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	9097000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1049522000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	939575000	usd
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	452392000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	740770000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	3323893000	usd
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2111773000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	17399000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	0	usd
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	0	usd
CY2022	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	493678000	usd
CY2021	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	0	usd
CY2020	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	0	usd
CY2022	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	63715000	usd
CY2021	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	6692000	usd
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	749000	usd
CY2022	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	94174000	usd
CY2021	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	2101000	usd
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	527000	usd
CY2022	ebc	Contributions To Low Income Housing Tax Credit Investments ContributionsToLowIncomeHousingTaxCreditInvestments	-19487000	usd
CY2021	ebc	Contributions To Low Income Housing Tax Credit Investments ContributionsToLowIncomeHousingTaxCreditInvestments	-11379000	usd
CY2020	ebc	Contributions To Low Income Housing Tax Credit Investments ContributionsToLowIncomeHousingTaxCreditInvestments	-12372000	usd
CY2022	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	788000	usd
CY2021	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	2519000	usd
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	4395000	usd
CY2022	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	1170000	usd
CY2021	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	337000	usd
CY2020	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	201000	usd
CY2022	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	20446000	usd
CY2021	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	usd
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1347000	usd
CY2022	ebc	Proceeds From Payments For Outstanding Loans ProceedsFromPaymentsForOutstandingLoans	926255000	usd
CY2021	ebc	Proceeds From Payments For Outstanding Loans ProceedsFromPaymentsForOutstandingLoans	-380807000	usd
CY2020	ebc	Proceeds From Payments For Outstanding Loans ProceedsFromPaymentsForOutstandingLoans	719041000	usd
CY2022	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	380234000	usd
CY2021	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	0	usd
CY2020	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	0	usd
CY2022	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	13400000	usd
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	13439000	usd
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	1363000	usd
CY2022	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	8627000	usd
CY2021	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	5728000	usd
CY2020	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	5144000	usd
CY2022	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	17313000	usd
CY2021	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	21981000	usd
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	usd
CY2022	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	0	usd
CY2021	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	125000	usd
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	646000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1076655000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1985744000	usd
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2390183000	usd
CY2022	us-gaap	Increase Decrease In Demand Deposits IncreaseDecreaseInDemandDeposits	-1751953000	usd
CY2021	us-gaap	Increase Decrease In Demand Deposits IncreaseDecreaseInDemandDeposits	1155868000	usd
CY2020	us-gaap	Increase Decrease In Demand Deposits IncreaseDecreaseInDemandDeposits	2674672000	usd
CY2022	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	1098001000	usd
CY2021	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-58144000	usd
CY2020	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-70280000	usd
CY2022	ebc	Proceeds From Repayments Of Borrowed Funds ProceedsFromRepaymentsOfBorrowedFunds	706550000	usd
CY2021	ebc	Proceeds From Repayments Of Borrowed Funds ProceedsFromRepaymentsOfBorrowedFunds	2580000	usd
CY2020	ebc	Proceeds From Repayments Of Borrowed Funds ProceedsFromRepaymentsOfBorrowedFunds	-207346000	usd
CY2022	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	0	usd
CY2021	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	36277000	usd
CY2020	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	0	usd
CY2022	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	668000	usd
CY2021	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	263000	usd
CY2020	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	165000	usd
CY2022	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	usd
CY2021	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	usd
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1792878000	usd
CY2022	ebc	Payments For Repurchase Of Employee Stock Ownership Plan PaymentsForRepurchaseOfEmployeeStockOwnershipPlan	0	usd
CY2021	ebc	Payments For Repurchase Of Employee Stock Ownership Plan PaymentsForRepurchaseOfEmployeeStockOwnershipPlan	0	usd
CY2020	ebc	Payments For Repurchase Of Employee Stock Ownership Plan PaymentsForRepurchaseOfEmployeeStockOwnershipPlan	149407000	usd
CY2022	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	usd
CY2021	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	usd
CY2020	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	28552000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	201618000	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	23224000	usd
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	usd
CY2022	us-gaap	Payments Of Dividends PaymentsOfDividends	65886000	usd
CY2021	us-gaap	Payments Of Dividends PaymentsOfDividends	51564000	usd
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	0	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-215574000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	988976000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	4011800000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-1062287000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-822278000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	1691468000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1231792000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2054070000	usd
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	362602000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	169505000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1231792000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2054070000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	35241000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	5354000	usd
CY2020	us-gaap	Interest Paid Net InterestPaidNet	13684000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	41751000	usd
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	43299000	usd
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	35128000	usd
CY2022	ebc	Net Increase In Capital Commitments Relating To Low Income Housing Tax Credit Projects NetIncreaseInCapitalCommitmentsRelatingToLowIncomeHousingTaxCreditProjects	55233000	usd
CY2021	ebc	Net Increase In Capital Commitments Relating To Low Income Housing Tax Credit Projects NetIncreaseInCapitalCommitmentsRelatingToLowIncomeHousingTaxCreditProjects	28291000	usd
CY2020	ebc	Net Increase In Capital Commitments Relating To Low Income Housing Tax Credit Projects NetIncreaseInCapitalCommitmentsRelatingToLowIncomeHousingTaxCreditProjects	25816000	usd
CY2022	ebc	Net Decrease In Operating Lease Right Of Use Assets And Operating Lease Liabilities Relating To Lease Remeasurements NetDecreaseInOperatingLeaseRightOfUseAssetsAndOperatingLeaseLiabilitiesRelatingToLeaseRemeasurements	14836000	usd
CY2021	ebc	Net Decrease In Operating Lease Right Of Use Assets And Operating Lease Liabilities Relating To Lease Remeasurements NetDecreaseInOperatingLeaseRightOfUseAssetsAndOperatingLeaseLiabilitiesRelatingToLeaseRemeasurements	0	usd
CY2020	ebc	Net Decrease In Operating Lease Right Of Use Assets And Operating Lease Liabilities Relating To Lease Remeasurements NetDecreaseInOperatingLeaseRightOfUseAssetsAndOperatingLeaseLiabilitiesRelatingToLeaseRemeasurements	0	usd
CY2022	ebc	Maturity Of Acquired Securities Sold Under Agreements To Repurchase Noncash MaturityOfAcquiredSecuritiesSoldUnderAgreementsToRepurchaseNoncash	0	usd
CY2021	ebc	Maturity Of Acquired Securities Sold Under Agreements To Repurchase Noncash MaturityOfAcquiredSecuritiesSoldUnderAgreementsToRepurchaseNoncash	274982000	usd
CY2020	ebc	Maturity Of Acquired Securities Sold Under Agreements To Repurchase Noncash MaturityOfAcquiredSecuritiesSoldUnderAgreementsToRepurchaseNoncash	0	usd
CY2022	ebc	Initial Recognition Of Operating Lease Rightofuse Assets Upon Adoption Of Accounting Standards Update InitialRecognitionOfOperatingLeaseRightofuseAssetsUponAdoptionOfAccountingStandardsUpdate	0	usd
CY2021	ebc	Initial Recognition Of Operating Lease Rightofuse Assets Upon Adoption Of Accounting Standards Update InitialRecognitionOfOperatingLeaseRightofuseAssetsUponAdoptionOfAccountingStandardsUpdate	0	usd
CY2020	ebc	Initial Recognition Of Operating Lease Rightofuse Assets Upon Adoption Of Accounting Standards Update InitialRecognitionOfOperatingLeaseRightofuseAssetsUponAdoptionOfAccountingStandardsUpdate	92948000	usd
CY2022	ebc	Initial Recognition Of Operating Lease Liabilities Upon Adoption Of Accounting Standards Update InitialRecognitionOfOperatingLeaseLiabilitiesUponAdoptionOfAccountingStandardsUpdate	0	usd
CY2021	ebc	Initial Recognition Of Operating Lease Liabilities Upon Adoption Of Accounting Standards Update InitialRecognitionOfOperatingLeaseLiabilitiesUponAdoptionOfAccountingStandardsUpdate	0	usd
CY2020	ebc	Initial Recognition Of Operating Lease Liabilities Upon Adoption Of Accounting Standards Update InitialRecognitionOfOperatingLeaseLiabilitiesUponAdoptionOfAccountingStandardsUpdate	96426000	usd
CY2020	ebc	Stock Issued During Period Value Charitable Donations StockIssuedDuringPeriodValueCharitableDonations	91300000	usd
CY2020Q4	us-gaap	Sale Of Stock Percentage Of Ownership After Transaction SaleOfStockPercentageOfOwnershipAfterTransaction	1
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	186758154	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	186758154	shares
CY2022	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:12pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-top:6pt;text-indent:54pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In preparing the Consolidated Financial Statements in conformity with GAAP, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the balance sheets and income and expenses for the periods reported. Actual results could differ from those estimates based on changing conditions, including economic conditions and future events. Material estimates that are particularly susceptible to change relate to the determination of the allowance for loan losses, valuation and fair value measurements, allowance for credit losses on investment securities, the liabilities for benefit obligations (particularly pensions), the provision for income taxes and impairment of goodwill and other intangibles.</span></div>
CY2022Q4	us-gaap	Restricted Cash RestrictedCash	1000000	usd
CY2021Q4	us-gaap	Restricted Cash RestrictedCash	21300000	usd
CY2022Q1	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss	0	usd
CY2022	us-gaap	Number Of Reporting Units NumberOfReportingUnits	2	reporting_unit
CY2022	ebc	Defined Benefit Plan Service Requirement For Full Vesting For Individuals Employed On Or Before October211989 DefinedBenefitPlanServiceRequirementForFullVestingForIndividualsEmployedOnOrBeforeOctober211989	P3Y
CY2022	ebc	Defined Benefit Plan Service Requirement For Full Vesting For Individuals Employed Subsequent To October311989 DefinedBenefitPlanServiceRequirementForFullVestingForIndividualsEmployedSubsequentToOctober311989	P5Y
CY2022	ebc	Defined Benefit Plan Service Requirement For Full Vesting For Individuals Who Were Not Already In The Defined Benefit Plan As Of November12020 DefinedBenefitPlanServiceRequirementForFullVestingForIndividualsWhoWereNotAlreadyInTheDefinedBenefitPlanAsOfNovember12020	P3Y
CY2022	ebc	Number Of Deferred Compensation Plans NumberOfDeferredCompensationPlans	3	plan
CY2022	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2021Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period Contractually Required Payments Receivable At Acquisition CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAcquiredDuringPeriodContractuallyRequiredPaymentsReceivableAtAcquisition	82900000	usd
CY2021Q4	ebc	Certain Loans Acquired In Transfer Accounted For As Debt Securities Acquired During Period Cash Flows Not Expected To Be Collected At Acquisition CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodCashFlowsNotExpectedToBeCollectedAtAcquisition	6746000	usd
CY2021Q4	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Acquired During Period Cash Flows Expected To Be Collected At Acquisition CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodCashFlowsExpectedToBeCollectedAtAcquisition	76154000	usd
CY2021Q4	ebc	Certain Loans Acquired In Transfer Accounted For As Debt Securities Acquired During Period Interest Component Of Cash Flows Expected To Be Collected At Acquisition CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodInterestComponentOfCashFlowsExpectedToBeCollectedAtAcquisition	8896000	usd
CY2021Q4	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Acquired During Period At Acquisition At Fair Value CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodAtAcquisitionAtFairValue	67258000	usd
CY2021Q4	ebc	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Operating Lease Liability BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiability	13900000	usd
CY2021Q4	ebc	Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Right Of Use Asset BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAsset	13900000	usd
CY2021	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	35456000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	7825435000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	9000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1134666000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	6690778000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	8587179000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	36492000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	112447000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	8511224000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	12900000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	14300000	usd
CY2022	us-gaap	Debt Securities Available For Sale Accrued Interest Writeoff DebtSecuritiesAvailableForSaleAccruedInterestWriteoff	0	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1775000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1166000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	288000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	4932000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	0	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	0	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-3157000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	1166000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	288000	usd
CY2021	us-gaap	Other Than Temporary Impairment Loss Debt Securities Available For Sale OtherThanTemporaryImpairmentLossDebtSecuritiesAvailableForSale	0	usd
CY2020	us-gaap	Other Than Temporary Impairment Loss Debt Securities Available For Sale OtherThanTemporaryImpairmentLossDebtSecuritiesAvailableForSale	0	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	802
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	98038000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	968376000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1036628000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	5719149000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	1134666000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6687525000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	470
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	85764000	usd
CY2022	us-gaap	Debt Securities Held To Maturity Accrued Interest Writeoff DebtSecuritiesHeldToMaturityAccruedInterestWriteoff	0	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	5993147000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	26683000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	810035000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	112447000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6803182000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss	476647000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	0	usd
CY2022Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	53421000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2022Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	423226000	usd
CY2021Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss	1000000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	1512000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1494000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	1211778000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1074080000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1643641000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1430761000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	4968504000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	4184443000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	7825435000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	6690778000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date Year One DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateYearOne	0	usd
CY2022Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year One Through Five DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive	0	usd
CY2022Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year5 Through10 DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear5Through10	200154000	usd
CY2022Q4	ebc	Amount Of Specific Reserve Associated With Troubled Debt Restructuring AmountOfSpecificReserveAssociatedWithTroubledDebtRestructuring	1800000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	176883000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year10 DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10	276493000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	246343000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDate	476647000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	423226000	usd
CY2022Q4	ebc	Debt Securities Amortized Cost Maturity Allocated And Single Maturity Date Year One DebtSecuritiesAmortizedCostMaturityAllocatedAndSingleMaturityDateYearOne	1512000	usd
CY2022Q4	ebc	Debt Securities Fair Value Maturity Allocated And Single Maturity Date Year One DebtSecuritiesFairValueMaturityAllocatedAndSingleMaturityDateYearOne	1494000	usd
CY2022Q4	ebc	Debt Securities Amortized Cost After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year One Through Five DebtSecuritiesAmortizedCostAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive	1211778000	usd
CY2022Q4	ebc	Debt Securities Fair Value Maturity Allocated And Single Maturity Date After Year One Through Five DebtSecuritiesFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive	1074080000	usd
CY2022Q4	ebc	Debt Securities Amortized Cost After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year Five Through Ten DebtSecuritiesAmortizedCostAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearFiveThroughTen	1843795000	usd
CY2022Q4	ebc	Debt Securities Fair Value Maturity Allocated And Single Maturity Date After Year5 Through10 DebtSecuritiesFairValueMaturityAllocatedAndSingleMaturityDateAfterYear5Through10	1607644000	usd
CY2022Q4	ebc	Debt Securities Amortized Cost After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year10 DebtSecuritiesAmortizedCostAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10	5244997000	usd
CY2022Q4	ebc	Debt Securities Fair Value Maturity Allocated And Single Maturity Date After Year10 DebtSecuritiesFairValueMaturityAllocatedAndSingleMaturityDateAfterYear10	4430786000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity Amortized Cost After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAndHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss	8302082000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity Fair Value DebtSecuritiesAvailableForSaleAndHeldToMaturityFairValue	7114004000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	51955000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	51932000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	784326000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	773349000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	2023620000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1994423000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	5727278000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	5691520000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss	8587179000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	8511224000	usd
CY2022Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	13575531000	usd
CY2021Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	12281510000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	142211000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	97787000	usd
CY2022Q4	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	-13003000	usd
CY2021Q4	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	-26442000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	13420317000	usd
CY2021Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	12157281000	usd
CY2022Q4	us-gaap	Credit Derivative Maximum Exposure Undiscounted CreditDerivativeMaximumExposureUndiscounted	100000000	usd
CY2022Q4	us-gaap	Participating Mortgage Loans Mortgage Obligations Amount ParticipatingMortgageLoansMortgageObligationsAmount	84000000	usd
CY2021Q4	us-gaap	Participating Mortgage Loans Mortgage Obligations Amount ParticipatingMortgageLoansMortgageObligationsAmount	95800000	usd
CY2022	us-gaap	Financing Receivable Significant Purchases FinancingReceivableSignificantPurchases	380200000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	97787000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	4831000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	4244000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	17925000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	142211000	usd
CY2022Q4	us-gaap	Financing Receivable Accrued Interest Before Allowance For Credit Loss FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss	45200000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	44400000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	142200000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	97800000	usd
CY2022	ebc	Financing Receivable Allowance For Credit Loss To Outstanding Percent Period Increase Decrease FinancingReceivableAllowanceForCreditLossToOutstandingPercentPeriodIncreaseDecrease	25
CY2022Q4	srt	Financing Receivable Allowance For Credit Loss To Outstanding Percent FinancingReceivableAllowanceForCreditLossToOutstandingPercent	0.0105
CY2021Q4	srt	Financing Receivable Allowance For Credit Loss To Outstanding Percent FinancingReceivableAllowanceForCreditLossToOutstandingPercent	0.0080
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	17300000	usd
CY2022	ebc	Financing Receivable Allowance For Credit Loss To Outstanding Percent Period Increase Decrease FinancingReceivableAllowanceForCreditLossToOutstandingPercentPeriodIncreaseDecrease	3
CY2022Q4	srt	Financing Receivable Allowance For Credit Loss To Outstanding Percent FinancingReceivableAllowanceForCreditLossToOutstandingPercent	0.0105
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	3481250000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	2447552000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	1630538000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	1094274000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	779687000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2496108000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	1614995000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan	18124000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	13562528000	usd
CY2022	ebc	Consumer Credit Exposures Period Past Due Required To Classify Loans As Special Mention Maximum ConsumerCreditExposuresPeriodPastDueRequiredToClassifyLoansAsSpecialMentionMaximum	P90D
CY2022	ebc	Consumer Credit Exposures Period Past Due Required To Classify Loans As Special Mention Maximum ConsumerCreditExposuresPeriodPastDueRequiredToClassifyLoansAsSpecialMentionMaximum	P90D
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	13562528000	usd
CY2021Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	12281510000	usd
CY2022Q4	ebc	Financing Receivable Nonaccrual With Allowance FinancingReceivableNonaccrualWithAllowance	26244000	usd
CY2022Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	12360000	usd
CY2022Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	38604000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruing	0	usd
CY2021Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	32993000	usd
CY2021Q4	us-gaap	Financing Receivable Excluding Accrued Interest90 Days Or More Past Due Still Accruing FinancingReceivableExcludingAccruedInterest90DaysOrMorePastDueStillAccruing	1990000	usd
CY2022	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	257	loan
CY2022Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	48185000	usd
CY2021	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	249	loan
CY2021Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	47535000	usd
CY2021Q4	ebc	Amount Of Specific Reserve Associated With Troubled Debt Restructuring AmountOfSpecificReserveAssociatedWithTroubledDebtRestructuring	3400000	usd
CY2021Q4	ebc	Financing Receivables Commitments To Lend Additional Funds FinancingReceivablesCommitmentsToLendAdditionalFunds	0	usd
CY2022Q4	ebc	Financing Receivables Commitments To Lend Additional Funds FinancingReceivablesCommitmentsToLendAdditionalFunds	0	usd
CY2022	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	51	contract
CY2022	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	12571000	usd
CY2022	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	12590000	usd
CY2021	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5	contract
CY2021	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	798000	usd
CY2021	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	798000	usd
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	40	contract
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	4235000	usd
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	4239000	usd
CY2022Q4	ebc	Investment Recorded Represented By Troubled Debt Restructuring In The Current Period InvestmentRecordedRepresentedByTroubledDebtRestructuringInTheCurrentPeriod	11000000	usd
CY2021Q4	ebc	Investment Recorded Represented By Troubled Debt Restructuring In The Current Period InvestmentRecordedRepresentedByTroubledDebtRestructuringInTheCurrentPeriod	800000	usd
CY2022	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	12590000	usd
CY2021	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	798000	usd
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	4239000	usd
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	contract
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	988000	usd
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	contract
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	usd
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	contract
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	40000	usd
CY2021	ebc	Amounts Charged Off On Td Rs AmountsChargedOffOnTDRs	0	usd
CY2022	ebc	Amounts Charged Off On Td Rs AmountsChargedOffOnTDRs	0	usd
CY2020	ebc	Amounts Charged Off On Td Rs AmountsChargedOffOnTDRs	200000	usd
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	113031000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	9002000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	3444000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	-9686000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	97787000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	3970000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	546000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Purchased With Credit Deterioration Allowance For Credit Loss At Acquisition Date FinancingReceivableExcludingAccruedInterestPurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate	93271000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	97787000	usd
CY2021	us-gaap	Financing Receivable Purchased With Credit Deterioration Amount At Purchase Price FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice	58204000	usd
CY2021Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	69639000	usd
CY2021Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	12153667000	usd
CY2021Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	12281510000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	33187000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	36330000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	25017000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	28786000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	3970000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	58204000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	65116000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	3970000	usd
CY2021	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	34637000	usd
CY2021	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod	956000	usd
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	39062000	usd
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod	1154000	usd
CY2021	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	35673000	usd
CY2021	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod	596000	usd
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	36782000	usd
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod	660000	usd
CY2021	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	70310000	usd
CY2021	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	1552000	usd
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	75844000	usd
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	1814000	usd
CY2020Q4	us-gaap	Certain Loans Acquired In Transfer Accretable Yield CertainLoansAcquiredInTransferAccretableYield	2495000	usd
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Accretable Yield CertainLoansAcquiredInTransferAccretableYield	3923000	usd
CY2021	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	8896000	usd
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	0	usd
CY2021	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	1194000	usd
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	1374000	usd
CY2021	ebc	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Other Cash Flow Changes CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesOtherCashFlowChanges	-1475000	usd
CY2020	ebc	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Other Cash Flow Changes CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesOtherCashFlowChanges	-185000	usd
CY2021	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	1649000	usd
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	131000	usd
CY2021Q4	us-gaap	Certain Loans Acquired In Transfer Accretable Yield CertainLoansAcquiredInTransferAccretableYield	10371000	usd
CY2020Q4	us-gaap	Certain Loans Acquired In Transfer Accretable Yield CertainLoansAcquiredInTransferAccretableYield	2495000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	156426000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	174420000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	93770000	usd
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	108564000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	62656000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	65856000	usd
CY2022Q4	us-gaap	Assets Held For Sale Not Part Of Disposal Group AssetsHeldForSaleNotPartOfDisposalGroup	0	usd
CY2021Q4	us-gaap	Assets Held For Sale Not Part Of Disposal Group AssetsHeldForSaleNotPartOfDisposalGroup	15128000	usd
CY2022Q4	ebc	Property Plant And Equipment Including Assets Held For Sale Not Part Of Disposal Group PropertyPlantAndEquipmentIncludingAssetsHeldForSaleNotPartOfDisposalGroup	62656000	usd
CY2021Q4	ebc	Property Plant And Equipment Including Assets Held For Sale Not Part Of Disposal Group PropertyPlantAndEquipmentIncludingAssetsHeldForSaleNotPartOfDisposalGroup	80984000	usd
CY2022	us-gaap	Depreciation Depreciation	11100000	usd
CY2021	us-gaap	Depreciation Depreciation	12000000	usd
CY2020	us-gaap	Depreciation Depreciation	13000000	usd
CY2022	ebc	Number Of Properties Sold NumberOfPropertiesSold	5	property
CY2022	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	17300000	usd
CY2021	ebc	Premises Transferred To Held For Sale PremisesTransferredToHeldForSale	37600000	usd
CY2021	ebc	Number Of Branch Locations Transferred To Held For Sale NumberOfBranchLocationsTransferredToHeldForSale	5	branch
CY2021	ebc	Gain Loss On Properties Transferred To Held For Sale GainLossOnPropertiesTransferredToHeldForSale	-1200000	usd
CY2021	ebc	Number Of Properties Sold NumberOfPropertiesSold	3	property
CY2021	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	22000000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	57428000	usd
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	83821000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	61209000	usd
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	89296000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	14483000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	14526000	usd
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	14402000	usd
CY2022	ebc	Finance Lease Cost FinanceLeaseCost	362000	usd
CY2021	ebc	Finance Lease Cost FinanceLeaseCost	191000	usd
CY2020	ebc	Finance Lease Cost FinanceLeaseCost	71000	usd
CY2022	us-gaap	Variable Lease Cost VariableLeaseCost	2746000	usd
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	1832000	usd
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	1982000	usd
CY2022	us-gaap	Lease Cost LeaseCost	17591000	usd
CY2021	us-gaap	Lease Cost LeaseCost	16549000	usd
CY2020	us-gaap	Lease Cost LeaseCost	16455000	usd
CY2022	ebc	Finance Lease Principal Payments And Operating Lease Payments FinanceLeasePrincipalPaymentsAndOperatingLeasePayments	17100000	usd
CY2021	ebc	Finance Lease Principal Payments And Operating Lease Payments FinanceLeasePrincipalPaymentsAndOperatingLeasePayments	15600000	usd
CY2020	ebc	Finance Lease Principal Payments And Operating Lease Payments FinanceLeasePrincipalPaymentsAndOperatingLeasePayments	14200000	usd
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y2M12D
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y9M29D
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0263
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0252
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	14081000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	11352000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	9255000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	8061000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	6747000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	17989000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	67485000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	6276000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	61209000	usd
CY2022	ebc	Operating Lease Number Of Extensions Not Exercised OperatingLeaseNumberOfExtensionsNotExercised	3	extension
CY2022	ebc	Operating Lease Number Of Extensions Exercised OperatingLeaseNumberOfExtensionsExercised	2	extension
CY2022	ebc	Net Decrease In Operating Lease Right Of Use Assets And Operating Lease Liabilities Relating To Lease Remeasurements NetDecreaseInOperatingLeaseRightOfUseAssetsAndOperatingLeaseLiabilitiesRelatingToLeaseRemeasurements	14800000	usd
CY2022	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	600000	usd
CY2021	ebc	Number Of Leases Terminated NumberOfLeasesTerminated	4	lease
CY2021Q4	ebc	Number Of Lease Locations Closed NumberOfLeaseLocationsClosed	3	location
CY2021Q4	ebc	Number Of Leases Sublet NumberOfLeasesSublet	5	lease
CY2022Q4	us-gaap	Goodwill Goodwill	640222000	usd
CY2022Q4	us-gaap	Other Intangible Assets Net OtherIntangibleAssetsNet	20904000	usd
CY2022Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	661126000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	631496000	usd
CY2021Q4	us-gaap	Other Intangible Assets Net OtherIntangibleAssetsNet	18207000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	20904000	usd
CY2021Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	649703000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	631496000	usd
CY2022	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	8726000	usd
CY2022	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2022Q4	us-gaap	Goodwill Goodwill	640222000	usd
CY2020Q4	us-gaap	Goodwill Goodwill	369477000	usd
CY2021	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	262019000	usd
CY2021	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2021Q4	us-gaap	Goodwill Goodwill	631496000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	53074000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	32170000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	48757000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	30550000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	18207000	usd
CY2022	us-gaap	Number Of Reporting Units NumberOfReportingUnits	2	reporting_unit
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3900000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2500000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2900000	usd
CY2022	us-gaap	Finite Lived Intangible Asset Useful Life FiniteLivedIntangibleAssetUsefulLife	P9Y10M24D
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	3831000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	3350000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	2889000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	2467000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	2102000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	6265000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	20904000	usd
CY2020	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	usd
CY2022	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	usd
CY2021	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	usd
CY2022Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	9500000000	usd
CY2021Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	10500000000	usd
CY2022Q4	us-gaap	Bank Overdrafts BankOverdrafts	2300000	usd
CY2021Q4	us-gaap	Bank Overdrafts BankOverdrafts	1600000	usd
CY2022Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	1575617000	usd
CY2022Q4	us-gaap	Time Deposits Weighted Average Interest Rate Maturities Year One TimeDepositsWeightedAverageInterestRateMaturitiesYearOne	0.970
CY2022Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	30617000	usd
CY2022Q4	us-gaap	Time Deposits Weighted Average Interest Rate Maturities Year Two TimeDepositsWeightedAverageInterestRateMaturitiesYearTwo	0.019
CY2022Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	9297000	usd
CY2022Q4	us-gaap	Time Deposits Weighted Average Interest Rate Maturities Year Three TimeDepositsWeightedAverageInterestRateMaturitiesYearThree	0.006
CY2022Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	5092000	usd
CY2022Q4	us-gaap	Time Deposits Weighted Average Interest Rate Maturities Year Four TimeDepositsWeightedAverageInterestRateMaturitiesYearFour	0.003
CY2022Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	3726000	usd
CY2022Q4	us-gaap	Time Deposits Weighted Average Interest Rate Maturities Year Five TimeDepositsWeightedAverageInterestRateMaturitiesYearFive	0.002
CY2022Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	33000	usd
CY2022Q4	us-gaap	Time Deposits Weighted Average Interest Rate Maturities Greater Than Five Years TimeDepositsWeightedAverageInterestRateMaturitiesGreaterThanFiveYears	0.000
CY2022Q4	us-gaap	Time Deposits TimeDeposits	1624382000	usd
CY2022Q4	us-gaap	Weighted Average Rate Domestic Deposit Certificates Of Deposit WeightedAverageRateDomesticDepositCertificatesOfDeposit	1.000
CY2022Q4	us-gaap	Deposit Liabilities Collateral Issued Financial Instruments DepositLiabilitiesCollateralIssuedFinancialInstruments	437900000	usd
CY2021Q4	us-gaap	Deposit Liabilities Collateral Issued Financial Instruments DepositLiabilitiesCollateralIssuedFinancialInstruments	2200000000	usd
CY2022Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	239100000	usd
CY2021Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	224000000	usd
CY2022Q4	ebc	Time Deposits Brokered TimeDepositsBrokered	928600000	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	691297000	usd
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	17000	usd
CY2022Q4	ebc	Escrow Deposits Of Borrowers EscrowDepositsOfBorrowers	22314000	usd
CY2021Q4	ebc	Escrow Deposits Of Borrowers EscrowDepositsOfBorrowers	20258000	usd
CY2022Q4	ebc	Interest Rate Swap Collateral Funds InterestRateSwapCollateralFunds	14430000	usd
CY2021Q4	ebc	Interest Rate Swap Collateral Funds InterestRateSwapCollateralFunds	0	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	12787000	usd
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	14003000	usd
CY2022Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	740828000	usd
CY2021Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	34278000	usd
CY2022	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	8506000	usd
CY2021	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	165000	usd
CY2020	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	762000	usd
CY2022	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	300000	usd
CY2021	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	200000	usd
CY2020	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	400000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56929000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34047000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13163000	usd
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2218
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.1804
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.3667
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56900000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34000000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13200000	usd
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.222
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.180
CY2021	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-11300000	usd
CY2022	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-700000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	-2100000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	39453000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	26114000	usd
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	23002000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	11453000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	13246000	usd
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	10520000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	50906000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	39360000	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	33522000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	3244000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-7747000	usd
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-13736000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2779000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2434000	usd
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-6623000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	6023000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5313000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-20359000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56929000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34047000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13163000	usd
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	53904000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	39630000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	7539000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	11244000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0438
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	12387000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0656
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	43000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0012
CY2022	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-700000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.0027
CY2021	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-11300000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.0599
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	12000000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.3343
CY2022	ebc	Effective Income Tax Rate Reconciliation Amortization Of Qualified Low Income Housing Investments Amount EffectiveIncomeTaxRateReconciliationAmortizationOfQualifiedLowIncomeHousingInvestmentsAmount	7503000	usd
CY2022	ebc	Effective Income Tax Rate Reconciliation Amortization Of Qualified Low Income Housing Investments Percent EffectiveIncomeTaxRateReconciliationAmortizationOfQualifiedLowIncomeHousingInvestmentsPercent	0.0292
CY2021	ebc	Effective Income Tax Rate Reconciliation Amortization Of Qualified Low Income Housing Investments Amount EffectiveIncomeTaxRateReconciliationAmortizationOfQualifiedLowIncomeHousingInvestmentsAmount	5753000	usd
CY2021	ebc	Effective Income Tax Rate Reconciliation Amortization Of Qualified Low Income Housing Investments Percent EffectiveIncomeTaxRateReconciliationAmortizationOfQualifiedLowIncomeHousingInvestmentsPercent	0.0305
CY2020	ebc	Effective Income Tax Rate Reconciliation Amortization Of Qualified Low Income Housing Investments Amount EffectiveIncomeTaxRateReconciliationAmortizationOfQualifiedLowIncomeHousingInvestmentsAmount	4977000	usd
CY2020	ebc	Effective Income Tax Rate Reconciliation Amortization Of Qualified Low Income Housing Investments Percent EffectiveIncomeTaxRateReconciliationAmortizationOfQualifiedLowIncomeHousingInvestmentsPercent	0.1386
CY2022	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	7300000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.0284
CY2021	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	6539000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.0346
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	7085000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.1973
CY2022	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	10298000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0401
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	5665000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0300
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	4091000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.1140
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	2576000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.0100
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-219000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.0012
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-220000	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.0061
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56929000	usd
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2218
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34047000	usd
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.1804
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13163000	usd
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.3667
CY2022Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	254502000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	17370000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	43686000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	30335000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	18192000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Deferred Gain On Sale Leaseback Transaction DeferredTaxAssetsDeferredGainOnSaleLeasebackTransaction	17447000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Deferred Gain On Sale Leaseback Transaction DeferredTaxAssetsDeferredGainOnSaleLeasebackTransaction	25389000	usd
CY2022Q4	ebc	Deferred Tax Asset Charitable Contribution Limitation Carryover DeferredTaxAssetCharitableContributionLimitationCarryover	12273000	usd
CY2021Q4	ebc	Deferred Tax Asset Charitable Contribution Limitation Carryover DeferredTaxAssetCharitableContributionLimitationCarryover	18278000	usd
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CY2021Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	10680000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	6294000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	6888000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	4287000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	3799000	usd
CY2022Q4	ebc	Deferred Tax Assets Fair Value Adjustments DeferredTaxAssetsFairValueAdjustments	4009000	usd
CY2021Q4	ebc	Deferred Tax Assets Fair Value Adjustments DeferredTaxAssetsFairValueAdjustments	3949000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	354000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	13996000	usd
CY2022Q4	ebc	Deferred Tax Assets Payment Protection Program Loans DeferredTaxAssetsPaymentProtectionProgramLoans	58000	usd
CY2021Q4	ebc	Deferred Tax Assets Payment Protection Program Loans DeferredTaxAssetsPaymentProtectionProgramLoans	2967000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	2083000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1783000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	371103000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	135434000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	0	usd
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	700000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	371103000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	134734000	usd
CY2022Q4	ebc	Deferred Tax Liabilities Amortization Of Intangibles DeferredTaxLiabilitiesAmortizationOfIntangibles	17565000	usd
CY2021Q4	ebc	Deferred Tax Liabilities Amortization Of Intangibles DeferredTaxLiabilitiesAmortizationOfIntangibles	17339000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	16383000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	23849000	usd
CY2022Q4	ebc	Deferred Tax Liabilities Partnerships DeferredTaxLiabilitiesPartnerships	2340000	usd
CY2021Q4	ebc	Deferred Tax Liabilities Partnerships DeferredTaxLiabilitiesPartnerships	3324000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	938000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	6482000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	0	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	2878000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2229000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	4327000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	39455000	usd
CY2021Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	58199000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	331648000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	76535000	usd
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CY2021	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-11300000	usd
CY2022	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-700000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	7923000	usd
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CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	usd
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CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	7923000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	2141000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	5782000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	7923000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	6000000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1500000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	2000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	500000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	2100000	usd
CY2022	ebc	Tax Interest And Penalties Reduction Resulting From Lapse Of Applicable Statute Of Limitations TaxInterestAndPenaltiesReductionResultingFromLapseOfApplicableStatuteOfLimitations	600000	usd
CY2022Q4	us-gaap	Decrease In Unrecognized Tax Benefits Is Reasonably Possible DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible	2300000	usd
CY2022Q4	ebc	Decrease In Tax Interest And Penalties Is Reasonably Possible DecreaseInTaxInterestAndPenaltiesIsReasonablyPossible	700000	usd
CY2022Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	0	usd
CY2021Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	0	usd
CY2022Q4	ebc	Federal Reserve Bank Stock No Tax Provision FederalReserveBankStockNoTaxProvision	20800000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	199759000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	154665000	usd
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	22738000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	179529613	shares
CY2021	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	186713020	shares
CY2020	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	186663593	shares
CY2022	us-gaap	Weighted Average Number Of Shares Employee Stock Ownership Plan Shares Not Committed To Be Released WeightedAverageNumberOfSharesEmployeeStockOwnershipPlanSharesNotCommittedToBeReleased	14019256	shares
CY2021	us-gaap	Weighted Average Number Of Shares Employee Stock Ownership Plan Shares Not Committed To Be Released WeightedAverageNumberOfSharesEmployeeStockOwnershipPlanSharesNotCommittedToBeReleased	14520684	shares
CY2020	us-gaap	Weighted Average Number Of Shares Employee Stock Ownership Plan Shares Not Committed To Be Released WeightedAverageNumberOfSharesEmployeeStockOwnershipPlanSharesNotCommittedToBeReleased	14851058	shares
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CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172192336	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	171812535	shares
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	138214	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	59721	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	165648571	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172252057	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	171812535	shares
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.21
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.90
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.13
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.21
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.90
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.13
CY2022	ebc	Affordable Housing Investment Tax Credits AffordableHousingInvestmentTaxCredits	131300000	usd
CY2021	ebc	Affordable Housing Investment Tax Credits AffordableHousingInvestmentTaxCredits	83800000	usd
CY2022Q4	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	128765000	usd
CY2021Q4	us-gaap	Amortization Method Qualified Affordable Housing Project Investments AmortizationMethodQualifiedAffordableHousingProjectInvestments	81035000	usd
CY2022Q4	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	84145000	usd
CY2021Q4	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	48399000	usd
CY2022	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	9146000	usd
CY2021	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	6484000	usd
CY2020	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	5033000	usd
CY2022	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	7503000	usd
CY2021	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	5753000	usd
CY2020	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	4977000	usd
CY2021Q4	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	9337900	shares
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CY2021Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	225000000	usd
CY2022Q3	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	8900000	shares
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CY2021Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	8202022	shares
CY2022Q1	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	987526	shares
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CY2022Q1	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	7214496	shares
CY2022Q1	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1109697	shares
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CY2022Q1	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	6104799	shares
CY2022Q1	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	769398	shares
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CY2022Q1	ebc	Treasury Stock Aggregate Shares Acquired TreasuryStockAggregateSharesAcquired	4002499	shares
CY2022Q1	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	5335401	shares
CY2022Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1194185	shares
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CY2022Q2	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	4141216	shares
CY2022Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1880381	shares
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CY2022Q2	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	2260835	shares
CY2022Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1141903	shares
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CY2022Q2	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	1118932	shares
CY2022Q3	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	909785	shares
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CY2022Q3	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	209147	shares
CY2022Q3	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
CY2022Q3	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	0
CY2022Q3	ebc	Treasury Stock Aggregate Shares Acquired TreasuryStockAggregateSharesAcquired	9128753	shares
CY2022Q3	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	209147	shares
CY2022Q3	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	571463	shares
CY2022Q3	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	20.33
CY2022Q3	ebc	Treasury Stock Aggregate Shares Acquired TreasuryStockAggregateSharesAcquired	9700216	shares
CY2022Q3	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	8537684	shares
CY2022Q4	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1094049	shares
CY2022Q4	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	20.32
CY2022Q4	ebc	Treasury Stock Aggregate Shares Acquired TreasuryStockAggregateSharesAcquired	10794265	shares
CY2022Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	7443635	shares
CY2022Q4	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	453885	shares
CY2022Q4	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	18.91
CY2022Q4	ebc	Treasury Stock Aggregate Shares Acquired TreasuryStockAggregateSharesAcquired	11248150	shares
CY2022Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	6989750	shares
CY2022Q4	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
CY2022Q4	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	0
CY2022Q4	ebc	Treasury Stock Aggregate Shares Acquired TreasuryStockAggregateSharesAcquired	11248150	shares
CY2022Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	6989750	shares
CY2022Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.10
CY2022Q1	us-gaap	Distributed Earnings DistributedEarnings	17100000	usd
CY2022Q1	us-gaap	Payments Of Dividends PaymentsOfDividends	16900000	usd
CY2022Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.10
CY2022Q2	us-gaap	Distributed Earnings DistributedEarnings	16700000	usd
CY2022Q2	us-gaap	Payments Of Dividends PaymentsOfDividends	16500000	usd
CY2022Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.10
CY2022Q3	us-gaap	Distributed Earnings DistributedEarnings	16500000	usd
CY2022Q3	us-gaap	Payments Of Dividends PaymentsOfDividends	16300000	usd
CY2022Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.10
CY2022Q4	us-gaap	Distributed Earnings DistributedEarnings	16300000	usd
CY2022Q4	us-gaap	Payments Of Dividends PaymentsOfDividends	16100000	usd
CY2021Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.06
CY2021Q1	us-gaap	Distributed Earnings DistributedEarnings	10300000	usd
CY2021Q1	us-gaap	Payments Of Dividends PaymentsOfDividends	10300000	usd
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.08
CY2021Q2	us-gaap	Distributed Earnings DistributedEarnings	13800000	usd
CY2021Q2	us-gaap	Payments Of Dividends PaymentsOfDividends	13800000	usd
CY2021Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.08
CY2021Q3	us-gaap	Distributed Earnings DistributedEarnings	13800000	usd
CY2021Q3	us-gaap	Payments Of Dividends PaymentsOfDividends	13800000	usd
CY2021Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.08
CY2021Q4	us-gaap	Distributed Earnings DistributedEarnings	13700000	usd
CY2021Q4	us-gaap	Payments Of Dividends PaymentsOfDividends	13700000	usd
CY2022Q4	us-gaap	Capital Capital	2906742000	usd
CY2022Q4	ebc	Banking Regulation Total Capital Ratio Actual BankingRegulationTotalCapitalRatioActual	0.1789
CY2022Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	1299657000	usd
CY2022Q4	us-gaap	Capital Required To Be Well Capitalized CapitalRequiredToBeWellCapitalized	1624571000	usd
CY2022Q4	us-gaap	Common Equity Tier One Capital CommonEquityTierOneCapital	2751694000	usd
CY2022Q4	us-gaap	Common Equity Tier One Capital Ratio CommonEquityTierOneCapitalRatio	0.1694
CY2022Q4	us-gaap	Common Equity Tier One Capital Required For Capital Adequacy CommonEquityTierOneCapitalRequiredForCapitalAdequacy	731057000	usd
CY2022Q4	us-gaap	Common Equity Tier One Capital Required To Be Well Capitalized CommonEquityTierOneCapitalRequiredToBeWellCapitalized	1055971000	usd
CY2022Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	2751694000	usd
CY2022Q4	ebc	Banking Regulation Tier One Risk Based Capital Ratio Actual BankingRegulationTierOneRiskBasedCapitalRatioActual	0.1694
CY2022Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	974743000	usd
CY2022Q4	us-gaap	Tier One Risk Based Capital Required To Be Well Capitalized TierOneRiskBasedCapitalRequiredToBeWellCapitalized	1299657000	usd
CY2022Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	2751694000	usd
CY2022Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.1203
CY2022Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	915233000	usd
CY2022Q4	us-gaap	Tier One Leverage Capital Required To Be Well Capitalized TierOneLeverageCapitalRequiredToBeWellCapitalized	1144041000	usd
CY2021Q4	us-gaap	Capital Capital	2939016000	usd
CY2021Q4	ebc	Banking Regulation Total Capital Ratio Actual BankingRegulationTotalCapitalRatioActual	0.1977
CY2021Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	1189466000	usd
CY2021Q4	us-gaap	Capital Required To Be Well Capitalized CapitalRequiredToBeWellCapitalized	1486832000	usd
CY2021Q4	us-gaap	Common Equity Tier One Capital CommonEquityTierOneCapital	2831102000	usd
CY2021Q4	us-gaap	Common Equity Tier One Capital Ratio CommonEquityTierOneCapitalRatio	0.1904
CY2021Q4	us-gaap	Common Equity Tier One Capital Required For Capital Adequacy CommonEquityTierOneCapitalRequiredForCapitalAdequacy	669075000	usd
CY2021Q4	us-gaap	Banking Regulation Common Equity Tier One Risk Based Capital Ratio Capital Adequacy Minimum BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum	0.045
CY2021Q4	us-gaap	Common Equity Tier One Capital Required To Be Well Capitalized CommonEquityTierOneCapitalRequiredToBeWellCapitalized	966441000	usd
CY2021Q4	us-gaap	Banking Regulation Common Equity Tier One Risk Based Capital Ratio Well Capitalized Minimum BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum	0.065
CY2021Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	2831102000	usd
CY2021Q4	ebc	Banking Regulation Tier One Risk Based Capital Ratio Actual BankingRegulationTierOneRiskBasedCapitalRatioActual	0.1904
CY2021Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	892099000	usd
CY2021Q4	ebc	Banking Regulation Tier One Risk Based Capital Ratio Capital Adequacy Minimum BankingRegulationTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum	0.06
CY2021Q4	us-gaap	Tier One Risk Based Capital Required To Be Well Capitalized TierOneRiskBasedCapitalRequiredToBeWellCapitalized	1189466000	usd
CY2021Q4	ebc	Banking Regulation Tier One Risk Based Capital Ratio Well Capitalized Minimum BankingRegulationTierOneRiskBasedCapitalRatioWellCapitalizedMinimum	0.08
CY2021Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	2831102000	usd
CY2021Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.1396
CY2021Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	811000000	usd
CY2021Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy To Average Assets TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets	0.04
CY2021Q4	us-gaap	Tier One Leverage Capital Required To Be Well Capitalized TierOneLeverageCapitalRequiredToBeWellCapitalized	1013750000	usd
CY2021Q4	us-gaap	Tier One Leverage Capital Required To Be Well Capitalized To Average Assets TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets	0.05
CY2022	ebc	Defined Benefit Plan Age Requirement DefinedBenefitPlanAgeRequirement	P21Y
CY2022	ebc	Defined Benefit Plan Service Requirement DefinedBenefitPlanServiceRequirement	P1Y
CY2022	ebc	Defined Benefit Plan Service Requirement For Full Vesting For Individuals Employed On Or Before October211989 DefinedBenefitPlanServiceRequirementForFullVestingForIndividualsEmployedOnOrBeforeOctober211989	P3Y
CY2022	ebc	Defined Benefit Plan Service Requirement For Full Vesting For Individuals Employed Subsequent To October311989 DefinedBenefitPlanServiceRequirementForFullVestingForIndividualsEmployedSubsequentToOctober311989	P5Y
CY2022	ebc	Defined Benefit Plan Service Requirement For Full Vesting For Individuals Who Were Not Already In The Defined Benefit Plan As Of November12020 DefinedBenefitPlanServiceRequirementForFullVestingForIndividualsWhoWereNotAlreadyInTheDefinedBenefitPlanAsOfNovember12020	P3Y
CY2022	ebc	Defined Benefit Plan Employer Discretionary Contribution Amount DefinedBenefitPlanEmployerDiscretionaryContributionAmount	7200000	usd
CY2021	ebc	Defined Benefit Plan Employer Discretionary Contribution Amount DefinedBenefitPlanEmployerDiscretionaryContributionAmount	0	usd
CY2022Q4	us-gaap	Defined Benefit Plan Expected Future Employer Contributions Current Fiscal Year DefinedBenefitPlanExpectedFutureEmployerContributionsCurrentFiscalYear	0	usd
CY2020	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	9657000	usd
CY2022	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	31382000	usd
CY2021	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	31660000	usd
CY2020	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	25970000	usd
CY2022	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	10582000	usd
CY2021	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	5694000	usd
CY2022	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	35486000	usd
CY2021	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	33333000	usd
CY2020	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	29610000	usd
CY2022	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-11882000	usd
CY2021	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-11796000	usd
CY2020	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-1931000	usd
CY2022	us-gaap	Defined Benefit Plan Actuarial Gain Loss Immediate Recognition As Component In Net Periodic Benefit Cost Credit DefinedBenefitPlanActuarialGainLossImmediateRecognitionAsComponentInNetPeriodicBenefitCostCredit	-11032000	usd
CY2021	us-gaap	Defined Benefit Plan Actuarial Gain Loss Immediate Recognition As Component In Net Periodic Benefit Cost Credit DefinedBenefitPlanActuarialGainLossImmediateRecognitionAsComponentInNetPeriodicBenefitCostCredit	-13400000	usd
CY2020	us-gaap	Defined Benefit Plan Actuarial Gain Loss Immediate Recognition As Component In Net Periodic Benefit Cost Credit DefinedBenefitPlanActuarialGainLossImmediateRecognitionAsComponentInNetPeriodicBenefitCostCredit	-10787000	usd
CY2022	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Settlements1 DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1	-12045000	usd
CY2021	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Settlements1 DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1	0	usd
CY2020	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Settlements1 DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1	0	usd
CY2022	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	17673000	usd
CY2021	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	5625000	usd
CY2020	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	14873000	usd
CY2022	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Settlements1 DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1	-12000000	usd
CY2022Q4	us-gaap	Other Commitment OtherCommitment	0	usd
CY2022	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	5000000	usd
CY2021	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	4600000	usd
CY2020	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	4400000	usd
CY2020Q4	us-gaap	Employee Stock Ownership Plan Esop Debt Structure Direct Loan Amount EmployeeStockOwnershipPlanESOPDebtStructureDirectLoanAmount	149400000	usd
CY2020Q4	us-gaap	Employee Stock Ownership Plan Esop Shares In Esop EmployeeStockOwnershipPlanESOPSharesInESOP	14940652	shares
CY2020Q4	ebc	Employee Stock Ownership Plan Esop Debt Structure Direct Loan Term EmployeeStockOwnershipPlanESOPDebtStructureDirectLoanTerm	P30Y
CY2022	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	9900000	usd
CY2021	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	9400000	usd
CY2020	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	2400000	usd
CY2022	ebc	Employee Stock Ownership Plan Esop Loan Payments From Esop EmployeeStockOwnershipPlanESOPLoanPaymentsFromESOP	7900000	usd
CY2022	ebc	Employee Stock Ownership Plan Esop Principal Payments From Esop EmployeeStockOwnershipPlanESOPPrincipalPaymentsFromESOP	3200000	usd
CY2022	us-gaap	Employee Stock Ownership Plan Esop Interest Payments From Esop EmployeeStockOwnershipPlanESOPInterestPaymentsFromESOP	4700000	usd
CY2021	ebc	Employee Stock Ownership Plan Esop Loan Payments From Esop EmployeeStockOwnershipPlanESOPLoanPaymentsFromESOP	7900000	usd
CY2021	ebc	Employee Stock Ownership Plan Esop Principal Payments From Esop EmployeeStockOwnershipPlanESOPPrincipalPaymentsFromESOP	3000000	usd
CY2021	us-gaap	Employee Stock Ownership Plan Esop Interest Payments From Esop EmployeeStockOwnershipPlanESOPInterestPaymentsFromESOP	4900000	usd
CY2020	us-gaap	Employee Stock Ownership Plan Esop Debt Structure Direct Loan Employer Cash Payments Used For Debt Service EmployeeStockOwnershipPlanESOPDebtStructureDirectLoanEmployerCashPaymentsUsedForDebtService	1000000	usd
CY2020Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Allocated Shares EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares	63690	shares
CY2020	ebc	Employee Stock Ownership Plan Esop Debt Payment Compensation Expense EmployeeStockOwnershipPlanESOPDebtPaymentCompensationExpense	900000	usd
CY2020	ebc	Employee Stock Ownership Plan Esop Accrued Loan Payment Compensation Expense EmployeeStockOwnershipPlanESOPAccruedLoanPaymentCompensationExpense	1500000	usd
CY2022Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Allocated Shares EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares	1046850	shares
CY2021Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Allocated Shares EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares	565134	shares
CY2022Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Committed To Be Released Shares EmployeeStockOwnershipPlanESOPNumberOfCommittedToBeReleasedShares	104464	shares
CY2021Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Committed To Be Released Shares EmployeeStockOwnershipPlanESOPNumberOfCommittedToBeReleasedShares	104464	shares
CY2022Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Suspense Shares EmployeeStockOwnershipPlanESOPNumberOfSuspenseShares	13769628	shares
CY2021Q4	us-gaap	Employee Stock Ownership Plan Esop Number Of Suspense Shares EmployeeStockOwnershipPlanESOPNumberOfSuspenseShares	14271054	shares
CY2022Q4	us-gaap	Employee Stock Ownership Plan Esop Shares In Esop EmployeeStockOwnershipPlanESOPSharesInESOP	14920942	shares
CY2021Q4	us-gaap	Employee Stock Ownership Plan Esop Shares In Esop EmployeeStockOwnershipPlanESOPSharesInESOP	14940652	shares
CY2022Q4	us-gaap	Employee Stock Ownership Plan Esop Deferred Shares Fair Value EmployeeStockOwnershipPlanESOPDeferredSharesFairValue	237526000	usd
CY2021Q4	us-gaap	Employee Stock Ownership Plan Esop Deferred Shares Fair Value EmployeeStockOwnershipPlanESOPDeferredSharesFairValue	287847000	usd
CY2022Q4	ebc	Liability Defined Contribution Plan LiabilityDefinedContributionPlan	17300000	usd
CY2021Q4	ebc	Liability Defined Contribution Plan LiabilityDefinedContributionPlan	33400000	usd
CY2022	ebc	Number Of Deferred Compensation Plans NumberOfDeferredCompensationPlans	3	plan
CY2022	ebc	Number Of Deferred Compensation Plans NumberOfDeferredCompensationPlans	3	plan
CY2022Q4	us-gaap	Deferred Compensation Arrangement With Individual Recorded Liability DeferredCompensationArrangementWithIndividualRecordedLiability	25400000	usd
CY2021Q4	us-gaap	Deferred Compensation Arrangement With Individual Recorded Liability DeferredCompensationArrangementWithIndividualRecordedLiability	31500000	usd
CY2021Q4	ebc	Share Based Compensation Arrangement By Share Based Payment Award Reduction Of Shares Available To Be Issued Upon Exercise Of Stock Options With Each Additional Restricted Stock Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardReductionOfSharesAvailableToBeIssuedUponExerciseOfStockOptionsWithEachAdditionalRestrictedStockGrant	3	shares
CY2021Q2	us-gaap	Loss Contingency New Claims Filed Number LossContingencyNewClaimsFiledNumber	2	settlement
CY2022Q1	us-gaap	Loss Contingency Loss In Period LossContingencyLossInPeriod	3300000	usd
CY2021Q4	us-gaap	Other Commitment OtherCommitment	0	usd
CY2022Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	2400000000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	-2401000	usd
CY2022	us-gaap	Maximum Length Of Time Hedged In Cash Flow Hedge1 MaximumLengthOfTimeHedgedInCashFlowHedge1	P5Y
CY2022	ebc	Other Comprehensive Income Loss Cash Flow Hedge Unrealized Gains For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeUnrealizedGainsForDiscontinuanceBeforeTax	0	usd
CY2021	ebc	Other Comprehensive Income Loss Cash Flow Hedge Unrealized Gains For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeUnrealizedGainsForDiscontinuanceBeforeTax	0	usd
CY2020	ebc	Other Comprehensive Income Loss Cash Flow Hedge Unrealized Gains For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeUnrealizedGainsForDiscontinuanceBeforeTax	57362000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceBeforeTax	-10193000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceBeforeTax	-31234000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceBeforeTax	-15889000	usd
CY2022Q4	us-gaap	Derivative Assets DerivativeAssets	23861000	usd
CY2021Q4	us-gaap	Derivative Assets DerivativeAssets	64714000	usd
CY2022Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	81422000	usd
CY2021Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	18593000	usd
CY2022Q4	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-69010000	usd
CY2021Q4	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	0	usd
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	46871000	usd
CY2022Q4	us-gaap	Other Comprehensive Income Loss Derivative Excluded Component Increase Decrease After Adjustments And Tax OtherComprehensiveIncomeLossDerivativeExcludedComponentIncreaseDecreaseAfterAdjustmentsAndTax	0	usd
CY2021Q4	us-gaap	Other Comprehensive Income Loss Derivative Excluded Component Increase Decrease After Adjustments And Tax OtherComprehensiveIncomeLossDerivativeExcludedComponentIncreaseDecreaseAfterAdjustmentsAndTax	0	usd
CY2020	us-gaap	Other Comprehensive Income Loss Derivative Excluded Component Increase Decrease After Adjustments And Tax OtherComprehensiveIncomeLossDerivativeExcludedComponentIncreaseDecreaseAfterAdjustmentsAndTax	0	usd
CY2022Q4	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	4511000	usd
CY2021Q4	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	5179000	usd
CY2020	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	-4081000	usd
CY2022Q4	ebc	Credit Exposure To Interest Swap In Excess Of Termination Values CreditExposureToInterestSwapInExcessOfTerminationValues	0	usd
CY2021Q4	ebc	Credit Exposure To Interest Swap In Excess Of Termination Values CreditExposureToInterestSwapInExcessOfTerminationValues	400000	usd
CY2022	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-200000	usd
CY2021	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-700000	usd
CY2020	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	900000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	176583000	usd
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	164196000	usd
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	154745000	usd
CY2022	us-gaap	Revenue Not From Contract With Customer Excluding Interest Income RevenueNotFromContractWithCustomerExcludingInterestIncome	-422000	usd
CY2021	us-gaap	Revenue Not From Contract With Customer Excluding Interest Income RevenueNotFromContractWithCustomerExcludingInterestIncome	28959000	usd
CY2020	us-gaap	Revenue Not From Contract With Customer Excluding Interest Income RevenueNotFromContractWithCustomerExcludingInterestIncome	23628000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	176161000	usd
CY2021	us-gaap	Noninterest Income NoninterestIncome	193155000	usd
CY2020	us-gaap	Noninterest Income NoninterestIncome	178373000	usd
CY2022Q4	ebc	Insurance Commission Receivable InsuranceCommissionReceivable	15100000	usd
CY2021Q4	ebc	Insurance Commission Receivable InsuranceCommissionReceivable	15600000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-1119774000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-253278000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-866496000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-143913000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-32983000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-110930000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	133862000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	35781000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	98081000	usd
CY2022Q4	us-gaap	Deferred Gain Loss On Discontinuation Of Interest Rate Fair Value Hedge DeferredGainLossOnDiscontinuationOfInterestRateFairValueHedge	41200000	usd
CY2022Q4	ebc	Deferred Gain Loss On Discontinuation Of Interest Rate Fair Value Hedge After Amortization DeferredGainLossOnDiscontinuationOfInterestRateFairValueHedgeAfterAmortization	100000	usd
CY2021Q4	ebc	Deferred Gain Loss On Discontinuation Of Interest Rate Fair Value Hedge After Amortization DeferredGainLossOnDiscontinuationOfInterestRateFairValueHedgeAfterAmortization	7400000	usd
CY2020Q4	ebc	Deferred Gain Loss On Discontinuation Of Interest Rate Fair Value Hedge After Amortization DeferredGainLossOnDiscontinuationOfInterestRateFairValueHedgeAfterAmortization	29800000	usd
CY2020	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	111444000	usd
CY2020	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-13363000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	98081000	usd
CY2021	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-88720000	usd
CY2021	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-22210000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-110930000	usd
CY2022	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-869941000	usd
CY2022	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	3445000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-866496000	usd
CY2022	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	568054000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	17925000	usd
CY2022	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	550129000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	176161000	usd
CY2022	us-gaap	Noninterest Expense NoninterestExpense	469602000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	256688000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	56929000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	199759000	usd
CY2022Q4	us-gaap	Assets Assets	22646858000	usd
CY2022Q4	us-gaap	Liabilities Liabilities	20175068000	usd
CY2021	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	429827000	usd
CY2021	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	-9686000	usd
CY2021	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	439513000	usd
CY2021	us-gaap	Noninterest Income NoninterestIncome	193155000	usd
CY2021	us-gaap	Noninterest Expense NoninterestExpense	443956000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	188712000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34047000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	154665000	usd
CY2021Q4	us-gaap	Assets Assets	23512128000	usd
CY2021Q4	us-gaap	Liabilities Liabilities	20105776000	usd
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	401251000	usd
CY2020	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	38800000	usd
CY2020	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	362451000	usd
CY2020	us-gaap	Noninterest Income NoninterestIncome	178373000	usd
CY2020	us-gaap	Noninterest Expense NoninterestExpense	504923000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	35901000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13163000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	22738000	usd
CY2020Q4	us-gaap	Assets Assets	15964190000	usd
CY2020Q4	us-gaap	Liabilities Liabilities	12536138000	usd
CY2022	dei	Auditor Name AuditorName	Ernst & Young LLP
CY2022	dei	Auditor Location AuditorLocation	Boston, Massachusetts
CY2022	dei	Auditor Firm AuditorFirmId	42

Files In Submission

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$EBC
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2023 Q1 Form 10-K Financial Statement

#000162828023005001 Filed on February 24, 2023

Income Statement

Balance Sheet

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Facts In Submission

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$EBC Eastern Bankshares, Inc. Stock $ebc

2023 Q1 Form 10-K Financial Statement

#000162828023005001 Filed on February 24, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$EBC
Eastern Bankshares, Inc. Stock $ebc