$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb

$bhlb Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000110813421000007 Filed on March 01, 2021

Income Statement

Concept	2019 Q4	2019 Q3	2019 Q2
Revenue	$114.7M	$118.3M	$109.1M
YoY Change	5.67%	9.09%	-0.74%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$6.849M	$6.715M
YoY Change		-8.77%	-4.79%
% of Gross Profit
Depreciation & Amortization	$4.700M	$4.300M	$4.300M
YoY Change	11.9%	10.26%	13.16%
% of Gross Profit
Operating Expenses		$6.849M	$6.715M
YoY Change		-8.77%	-4.79%
Operating Profit
YoY Change
Interest Expense	$34.11M	$36.85M	$37.64M
YoY Change	0.53%	26.28%	49.42%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$39.06M	$24.67M	$29.07M
YoY Change	82.07%	-41.5%	-30.54%
Income Tax	$6.421M	$4.007M	$5.118M
% Of Pretax Income	16.44%	16.25%	17.6%
Net Earnings	$25.75M	$22.62M	$25.45M
YoY Change	80.59%	-29.82%	-25.22%
Net Earnings / Revenue	22.45%	19.12%	23.32%
Basic Earnings Per Share	$0.51	$0.44	$0.52
Diluted Earnings Per Share	$0.51	$0.44	$0.52
COMMON SHARES
Basic Shares Outstanding	50.49M shares	51.42M shares	48.96M shares
Diluted Shares Outstanding	50.70M shares	51.55M shares	49.11M shares

Balance Sheet

Concept	2019 Q4	2019 Q3	2019 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$621.4M	$361.7M	$288.9M
YoY Change	159.1%	85.04%	45.33%
Cash & Equivalents	$579.8M	$302.1M	$229.3M
Short-Term Investments	$41.56M	$59.60M	$59.58M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$120.4M	$123.2M	$121.6M
YoY Change	11.1%	10.86%	8.38%
Goodwill	$553.8M	$554.7M	$554.7M
YoY Change	6.84%	7.02%	6.85%
Intangibles	$45.62M	$47.20M	$48.72M
YoY Change	36.5%	36.33%	35.96%
Long-Term Investments
YoY Change
Other Assets	$205.0M	$292.0M	$264.0M
YoY Change	425.64%	412.28%	388.89%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$13.22B	$13.53B	$13.65B
YoY Change	8.22%	12.48%	14.72%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$81.00M	$83.00M	$85.00M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$125.0M	$300.0M	$608.9M
YoY Change	-88.83%	-74.75%	-39.23%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$81.00M	$83.00M	$85.00M
YoY Change		-93.01%	-91.52%
LONG-TERM LIABILITIES
Long-Term Debt	$108.0M	$108.0M	$108.0M
YoY Change	20.0%	21.35%	21.35%
Other Long-Term Liabilities	$202.0M	$241.0M	$210.0M
YoY Change	27.04%	25.52%	14.75%
Total Long-Term Liabilities	$310.0M	$349.0M	$318.0M
YoY Change	24.5%	24.2%	16.91%
TOTAL LIABILITIES
Total Short-Term Liabilities	$81.00M	$83.00M	$85.00M
Total Long-Term Liabilities	$310.0M	$349.0M	$318.0M
Total Liabilities	$11.46B	$11.76B	$11.87B
YoY Change	7.49%	12.02%	14.33%
SHAREHOLDERS EQUITY
Retained Earnings	$361.1M	$347.0M	$336.5M
YoY Change	16.92%	13.66%	18.81%
Common Stock	$1.423B	$1.423B	$1.422B
YoY Change	14.25%	14.27%	14.2%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$69.64M	$44.66M	$24.06M
YoY Change	217.07%	107.95%	12.25%
Treasury Stock Shares	2.318M shares	1.509M shares	858.0K shares
Shareholders Equity	$1.759B	$1.772B	$1.780B
YoY Change
Total Liabilities & Shareholders Equity	$13.22B	$13.53B	$13.65B
YoY Change	8.22%	12.48%	14.72%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2019 Q2
OPERATING ACTIVITIES
Net Income	$25.75M	$22.62M	$25.45M
YoY Change	80.59%	-29.82%	-25.22%
Depreciation, Depletion And Amortization	$4.700M	$4.300M	$4.300M
YoY Change	11.9%	10.26%	13.16%
Cash From Operating Activities	$107.8M	$29.80M	-$5.900M
YoY Change	165.52%	-73.1%	-56.62%
INVESTING ACTIVITIES
Capital Expenditures	-$2.100M	-$4.400M	-$1.700M
YoY Change	2000.0%	175.0%	-52.78%
Acquisitions
YoY Change
Other Investing Activities	$467.5M	$225.1M	$378.7M
YoY Change	-364.12%	-209.32%	-244.65%
Cash From Investing Activities	$465.5M	$220.7M	$376.9M
YoY Change	-362.99%	-206.31%	-242.01%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-295.6M	-177.7M	-309.4M
YoY Change	-260.74%	-290.05%	-205.17%
NET CHANGE
Cash From Operating Activities	107.8M	29.80M	-5.900M
Cash From Investing Activities	465.5M	220.7M	376.9M
Cash From Financing Activities	-295.6M	-177.7M	-309.4M
Net Change In Cash	277.7M	72.80M	61.60M
YoY Change	484.63%	-2306.06%	305.26%
FREE CASH FLOW
Cash From Operating Activities	$107.8M	$29.80M	-$5.900M
Capital Expenditures	-$2.100M	-$4.400M	-$1.700M
Free Cash Flow	$109.9M	$34.20M	-$4.200M
YoY Change	170.02%	-69.57%	-58.0%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020	us-gaap	Professional Fees ProfessionalFees	11907000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	10798000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	7343000	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	5876000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3861000	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	5734000	USD
CY2020	bhlb	Other Real Estate Owned OtherRealEstateOwned	125000	USD
CY2019	bhlb	Other Real Estate Owned OtherRealEstateOwned	154000	USD
CY2018	bhlb	Other Real Estate Owned OtherRealEstateOwned	68000	USD
CY2020	us-gaap	Adjustment For Amortization AdjustmentForAmortization	6181000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5783000	USD
CY2018	us-gaap	Adjustment For Amortization AdjustmentForAmortization	4934000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	553762000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	5839000	USD
CY2019	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	28046000	USD
CY2018	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	22144000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	29283000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	29726000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	23880000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	840239000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	289857000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	266893000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-533028000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	123984000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	138180000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	109219000	USD
CY2020	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	-26855000	USD
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	-5539000	USD
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	-4767000	USD
CY2020	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-7013000	USD
CY2019	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1468000	USD
CY2018	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1313000	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-19842000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-3454000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	313000	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	960000	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	918000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-533330000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	96490000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	104847000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	-10.21
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.06
CY2018	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.38
CY2020	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.39
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.08
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.08
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-10.60
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.30
CY2020	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	-10.21
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.05
CY2018	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.36
CY2020	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.39
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.08
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.07
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-10.60
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.97
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.29
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50270000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49263000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46024000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50270000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49421000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46231000	shares
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	25726000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	34530000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-16923000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	489000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	270000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-336000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	25237000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	34260000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-16587000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	6471000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	8873000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-4421000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	112000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	76000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-108000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	6359000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	8797000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-4313000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	18878000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-514139000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	122913000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	93491000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	1496264000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	93491000	USD
CY2018	us-gaap	Tax Cuts And Jobs Act Of2017 Reclassification From Aoci To Retained Earnings Tax Effect TaxCutsAndJobsActOf2017ReclassificationFromAociToRetainedEarningsTaxEffect	0	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.88
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	39966000	USD
CY2018	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	1.76
CY2018	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	918000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	326000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4759000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	1038000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1552918000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	122913000	USD
CY2019	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	176712000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.92
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	44147000	USD
CY2019	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	1.84
CY2019	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	960000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	52746000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	188000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4812000	USD
CY2019	us-gaap	Stockholders Equity Other StockholdersEquityOther	1126000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1758564000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	18878000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-514139000	USD
CY2020	us-gaap	Stock Issued During Period Value Conversion Of Convertible Securities StockIssuedDuringPeriodValueConversionOfConvertibleSecurities	0	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.72
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	36251000	USD
CY2020	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	1.20
CY2020	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	313000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	473000	USD
CY2020	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	664000	USD
CY2020	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4727000	USD
CY2020	us-gaap	Stockholders Equity Other StockholdersEquityOther	626000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1187773000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	109219000	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-19842000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-3454000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	75878000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	35419000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25451000	USD
CY2020	bhlb	Amortization Of Securities AmortizationOfSecurities	-2513000	USD
CY2019	bhlb	Amortization Of Securities AmortizationOfSecurities	-2407000	USD
CY2018	bhlb	Amortization Of Securities AmortizationOfSecurities	-2837000	USD
CY2020	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-21856000	USD
CY2019	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-12759000	USD
CY2018	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	1004000	USD
CY2020	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	11919000	USD
CY2019	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	10921000	USD
CY2018	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	10442000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	4727000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	4812000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	4759000	USD
CY2020	bhlb	Accretion Of Purchase Accounting Entries AccretionOfPurchaseAccountingEntries	-10377000	USD
CY2019	bhlb	Accretion Of Purchase Accounting Entries AccretionOfPurchaseAccountingEntries	-14813000	USD
CY2018	bhlb	Accretion Of Purchase Accounting Entries AccretionOfPurchaseAccountingEntries	-24000000	USD
CY2020	us-gaap	Adjustment For Amortization AdjustmentForAmortization	6181000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5783000	USD
CY2018	us-gaap	Adjustment For Amortization AdjustmentForAmortization	4934000	USD
CY2020	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	5354000	USD
CY2019	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	5349000	USD
CY2018	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	6232000	USD
CY2020	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	-7576000	USD
CY2019	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	4389000	USD
CY2018	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	-3719000	USD
CY2020	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	4267000	USD
CY2019	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	5137000	USD
CY2018	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	-1460000	USD
CY2020	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-327000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-3443000	USD
CY2018	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-152000	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-13000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-5000	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-30601000	USD
CY2020	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	3645000	USD
CY2019	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	6455000	USD
CY2018	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	4618000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	553762000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	31247000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	23418000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	123977000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	130419000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	166956000	USD
CY2020	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	103664000	USD
CY2019	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	-18894000	USD
CY2018	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	55298000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	227641000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	111525000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	222254000	USD
CY2020	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-734000	USD
CY2019	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-701000	USD
CY2018	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-665000	USD
CY2020	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	17631000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	23841000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	24538000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	33928000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	43075000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	38104000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	885182000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	119671000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	257547000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	69337000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	136229000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	499000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	457586000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	240586000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	188076000	USD
CY2020	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	144651000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	7260000	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	15391000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	35331000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	21602000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	36746000	USD
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-1054029000	USD
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-694657000	USD
CY2018	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	801876000	USD
CY2020	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	110774000	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	USD
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	553000	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2451000	USD
CY2018	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	854000	USD
CY2020	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	6741000	USD
CY2019	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	112208000	USD
CY2018	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	76090000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	19887000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	149455000	USD
CY2018	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	61831000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	7280000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4387000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4724000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7208000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	10565000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9349000	USD
CY2020	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	37988000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	81147000	USD
CY2018	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	0	USD
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	171000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	150000	USD
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	1600000	USD
CY2020	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	252000	USD
CY2019	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-313000	USD
CY2018	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-377000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	641103000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1202582000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-861517000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	499657000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	23996000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	233704000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	326277000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	5384982000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	4767766000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	582648000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	6228780000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	4387223000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	473000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	52746000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	664000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	188000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	326000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	36564000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	45107000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	40884000	USD
CY2020	bhlb	Settlementof Derivative Contractswith Institutional Counterparties SettlementofDerivativeContractswithInstitutionalCounterparties	97611000	USD
CY2019	bhlb	Settlementof Derivative Contractswith Institutional Counterparties SettlementofDerivativeContractswithInstitutionalCounterparties	0	USD
CY2018	bhlb	Settlementof Derivative Contractswith Institutional Counterparties SettlementofDerivativeContractswithInstitutionalCounterparties	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	109302000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-917467000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	573689000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	978046000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	396640000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-65574000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	579829000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	183189000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	248763000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1557875000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	579829000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	183189000	USD
CY2020	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	82319000	USD
CY2019	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	119695000	USD
CY2018	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	74565000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	21277000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	33406000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	32274000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-13864000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	19818000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	3029000	USD
CY2020	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	0	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	1595054000	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	0	USD
CY2020	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	0	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	1530010000	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	18878000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2020	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	14845000	USD
CY2019	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	120307000	USD
CY2018	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	0	USD
CY2020	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	224000	USD
CY2019	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	0	USD
CY2018	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	1600000	USD
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:700;line-height:120%">Reclassifications</span></div><div style="margin-top:2.7pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">Certain items in prior financial statements have been reclassified to conform to the current presentation.</span></div>
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the financial statements. Actual results could differ from those estimates.</span></div><div><span><br/></span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">Refer to Note 17 – Other Commitments, Contingencies, and Off-Balance Sheet Activities for pandemic related risks and uncertainties.</span></div>
CY2020	bhlb	Threshold Period Past Due For Financing Receivable Excluding Automobile Loans Not Accrue Interest ThresholdPeriodPastDueForFinancingReceivableExcludingAutomobileLoansNotAccrueInterest	P90D
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts	<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:700;line-height:115%">Allowance for Credit Losses for Loans</span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">The allowance for credit losses for loans (“ACLL”) is comprised of the allowance for loan losses and the allowance for unfunded commitments which is accounted for as a separate liability in other liabilities on the consolidated balance sheet. The ACLL is a valuation account that is deducted from the loans’ amortized cost basis to present the net amount expected to be collected on the loans. Loans are charged off against the allowance when management believes the uncollectibility of a loan balance is confirmed. Accrued interest receivable is excluded from the estimate of credit losses.</span></div><div><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">The level of the ACLL represents management’s estimate of expected credit losses over the expected life of the loans at the balance sheet date. The Company uses a static pool migration analysis method, applying expected historical loss trend and observed economic metrics. The level of the ACLL is based on management’s ongoing review of all relevant information, from internal and external sources, relating to past and current events, utilizing a 7 quarter reasonable and supportable forecast period with a 1 year reversion period. The ACLL reserve is overlaid with qualitative factors based upon:</span></div><div style="padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%;padding-left:13.8pt">the existence and growth of concentrations of credit;</span></div><div style="padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%;padding-left:13.8pt">the volume and severity of past due financial assets, including nonaccrual assets;</span></div><div style="padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%;padding-left:13.8pt">the institutions lending and credit review as well as the experience and ability of relevant management and staff and;</span></div><div style="padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%;padding-left:13.8pt">the effect of other external factors such as regulatory, competition, regional market conditions, legal and technological environment and other events such as natural disasters;</span></div><div style="padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%;padding-left:13.8pt">the effect of other economic factors such as economic stimulus and customer forbearance programs.</span></div><div><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">The allowance for unfunded commitments is maintained at a level by the Company to be sufficient to absorb expected lifetime losses related to unfunded credit facilities (including unfunded loan commitments and letters of credit).</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">The ACLL is measured on a collective (pool) basis when similar risk characteristics exist. The Company evaluates its risk characteristics of loans based on regulatory call report code with sub-segmentation based on underlying collateral for certain loan types. Risk characteristics relevant to each portfolio segment are as follows:</span></div><div style="padding-left:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:400;line-height:115%">Construction</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%"> – Loans in this segment primarily include real estate development loans for which payment is derived from sale of the property or long term financing at completion. Credit risk is affected by cost overruns, time to sell at an adequate price, and market conditions.</span></div><div><span><br/></span></div><div style="padding-left:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:400;line-height:115%">Commercial real estate multifamily, owner occupied and non-owner</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%"> – Loans in this segment are primarily owner-occupied or income-producing properties throughout New England and Northeastern New York. The underlying cash flows generated by the properties are adversely impacted by a downturn in the economy, which in turn, will have an effect on the credit quality in this segment. Management monitors the cash flows of these loans. </span></div><div><span><br/></span></div><div style="padding-left:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:400;line-height:115%">Commercial and industrial loans</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%"> – Loans in this segment are made to businesses and are generally secured by assets of the business such as accounts receivable, inventory, marketable securities, other liquid collateral, equipment and other business assets. Repayment is expected from the cash flows of the business. Loans in this segment include asset based loans which generally have no scheduled repayment which are closely monitored against formula based collateral advance ratios. A weakened economy, and resultant decreased consumer spending, will have an effect on the credit quality of this segment. </span></div><div style="padding-left:36pt"><span><br/></span></div><div style="padding-left:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:400;line-height:115%">Residential real estate</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%"> – All loans in this segment are collateralized by residential real estate and repayment is dependent on the credit quality of the individual borrower. The overall health of the economy, including unemployment rates and housing prices, will have an effect on the credit quality in this segment.</span></div><div style="padding-left:36pt"><span><br/></span></div><div style="padding-left:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-style:italic;font-weight:400;line-height:115%">Home equity and other consumer loans</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%"> – Loans in this segment are primarily home equity lines of credit, automobile loans and other consumer loans. The overall health of the economy, including unemployment rates and housing prices, will have an effect on the credit quality in this segment.</span></div><div><span><br/></span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:115%">Loans that do not share risk characteristics are evaluated on an individual basis, which the Company has determined to be non-accrual loans over a threshold, loans that were determined to be Troubled Debt Restructurings (“TDRs”) and PCD loans. Loans evaluated individually are not also included in the collective evaluation. Estimates of specific allowance may be determined by the present value of anticipated future cash flows or the loan’s observable fair market value, or the fair value of the collateral less costs to sell, if the loan is collateral dependent. However, for collateral dependent loans, the amount of the amortized cost in a loan that exceeds the fair value of the collateral is charged-off against the allowance for loan losses in lieu of an allocation of a specific allowance amount when such an amount has been identified definitively as uncollectible.</span></div>
CY2020Q4	us-gaap	Trading Securities TradingSecurities	9700000	USD
CY2020	bhlb	Defined Benefit Plan Net Actuarial Gain Loss Threshold Percentage For Amortization In Net Periodic Benefit Cost Minimum DefinedBenefitPlanNetActuarialGainLossThresholdPercentageForAmortizationInNetPeriodicBenefitCostMinimum	0.10
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	segment
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	63575000	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	100000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	9502428000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	9502428000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	9502428000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	361082000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	0	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	18300000	USD
CY2020Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	8700000	USD
CY2019Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	9400000	USD
CY2019Q4	us-gaap	Trading Securities TradingSecurities	10800000	USD
CY2020	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	300000	USD
CY2019	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	300000	USD
CY2018	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	400000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1653977000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	41816000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	561000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1695232000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	465091000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	26976000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	212000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	491855000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	104000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	18061000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	767000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	315000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	18513000	USD
CY2020Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAmortizedCost	2137129000	USD
CY2020Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Gainbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedGainbeforeTax	69559000	USD
CY2020Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Lossbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedLossbeforeTax	1088000	USD
CY2020Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNI	2205600000	USD
CY2020Q4	bhlb	Debt Securities Availableforsale And Heldtomaturity Allowance For Credit Losses DebtSecuritiesAvailableforsaleAndHeldtomaturityAllowanceForCreditLosses	104000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1297339000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	16503000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	2287000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1311555000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	357979000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	16263000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	965000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	373277000	USD
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	37138000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	5147000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	729000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	41556000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAmortizedCost	1692456000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Gainbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedGainbeforeTax	37913000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Lossbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedLossbeforeTax	3981000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNI	1726388000	USD
CY2019Q4	bhlb	Debt Securities Availableforsale And Heldtomaturity Allowance For Credit Losses DebtSecuritiesAvailableforsaleAndHeldtomaturityAllowanceForCreditLosses	0	USD
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	205000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	104000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis	33248000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Fair Value AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	33265000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	1950000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Next Rolling Twelve Months Fair Value HeldToMaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	1952000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis	8148000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	8276000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	3216000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling Year Two Through Five Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	3233000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis	67952000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	69619000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	23050000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling Year Six Through Ten Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	24026000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis	92103000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue	100464000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	221968000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingAfterTenYearsFairValue	241172000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	201451000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	211624000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	250184000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	270383000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	1452526000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	1483608000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	214907000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	221472000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1653977000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1695232000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	465091000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	491855000	USD
CY2020Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Amortized Cost SecurityOwnedAndPledgedAsCollateralForInterestRateSwapAmortizedCost	37532000	USD
CY2020Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Fair Value SecurityOwnedAndPledgedAsCollateralForInterestRateSwapFairValue	37815000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Amortized Cost SecurityOwnedAndPledgedAsCollateralForInterestRateSwapAmortizedCost	25728000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Fair Value SecurityOwnedAndPledgedAsCollateralForInterestRateSwapFairValue	25828000	USD
CY2020Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Amortized Cost SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsAmortizedCost	156047000	USD
CY2020Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Fair Value SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsFairValue	166570000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Amortized Cost SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsAmortizedCost	168740000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Fair Value SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsFairValue	175719000	USD
CY2020Q4	bhlb	Security Owned And Pledged As Collateral Amortized Cost SecurityOwnedAndPledgedAsCollateralAmortizedCost	193579000	USD
CY2020Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	204385000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral Amortized Cost SecurityOwnedAndPledgedAsCollateralAmortizedCost	194468000	USD
CY2019Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	201547000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	885000000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	120000000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	69000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	136000000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	4602000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	7492000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	3256000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedLossExcludingOtherThanTemporaryImpairment	11133000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedLossExcludingOtherThanTemporaryImpairment	3103000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedLossExcludingOtherThanTemporaryImpairment	6975000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	-6531000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	4389000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	-3719000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	551000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	174147000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	10000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1286000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	561000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	175433000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	212000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	55974000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	212000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	55974000	USD
CY2020Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLosses	763000	USD
CY2020Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan Twelve Months Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue	230121000	USD
CY2020Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLosses	10000	USD
CY2020Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Twelve Monthsor Longer Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue	1286000	USD
CY2020Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses	773000	USD
CY2020Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionFairValue	231407000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1287000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	180826000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	83773000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	2287000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	264599000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	55000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	10578000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	910000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	6925000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	965000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	17503000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLosses	1342000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan Twelve Months Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue	191404000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLosses	1910000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Twelve Monthsor Longer Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue	90698000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses	3252000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionFairValue	282102000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	9502428000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	63575000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	8081519000	USD
CY2020Q1	us-gaap	Notes Receivable Gross NotesReceivableGross	9502428000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	127302000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	63575000	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	7954217000	USD
CY2020Q1	us-gaap	Notes Receivable Net NotesReceivableNet	9438853000	USD
CY2020	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	98000000	USD
CY2020	us-gaap	Proceeds From Sale Of Loans And Leases Held For Investment ProceedsFromSaleOfLoansAndLeasesHeldForInvestment	415000000	USD
CY2019	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	432000000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans And Leases Held For Investment ProceedsFromSaleOfLoansAndLeasesHeldForInvestment	310000000	USD
CY2020	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	10600000	USD
CY2019	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	12000000.0	USD
CY2018	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	9300000	USD
CY2020Q4	us-gaap	Loans Pledged As Collateral LoansPledgedAsCollateral	925000000	USD
CY2020Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	2000000.0	USD
CY2019Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	1800000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	1100000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	1000000.0	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	63575000	USD
CY2020	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	45795000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	8005000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	76083000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	127302000	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	100000	USD
CY2020	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-464000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	7629000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	92708000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	7988811000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	8081519000	USD
CY2020Q1	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	39640000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	64948000	USD
CY2020Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	27418000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	11450000	USD
CY2020Q4	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	19316000	USD
CY2020	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	6257000	USD
CY2020	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2020	bhlb	Financing Receivable Troubled Debt Restructuring Other Increase Decrease FinancingReceivableTroubledDebtRestructuringOtherIncreaseDecrease	-4708000	USD
CY2020	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	12197000	USD
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	20548000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	16000	Loan
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	12197000	USD
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	12197000	USD
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	10000	Loan
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	13000	Loan
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	2063000	USD
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	2063000	USD
CY2018	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	2685000	USD
CY2018	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	2685000	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	Loan
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	Loan
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	Loan
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	195000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	9502428000	USD
CY2019Q4	bhlb	Unamortized Loan Origination Fees UnamortizedLoanOriginationFees	13259000	USD
CY2019Q4	bhlb	Unamortized Discounts Or Premiums UnamortizedDiscountsOrPremiums	2643000	USD
CY2019Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	15902000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	2840000	USD
CY2017Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	11561000	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldAdditions	4200000	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldAdditions	0	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	9619000	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	23109000	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	7430000	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	17347000	USD
CY2019	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Payments Received CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldPaymentsReceived	837000	USD
CY2018	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Payments Received CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldPaymentsReceived	2878000	USD
CY2019	bhlb	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassification To Troubled Debt Restructuring CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationToTroubledDebtRestructuring	9000	USD
CY2018	bhlb	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassification To Troubled Debt Restructuring CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationToTroubledDebtRestructuring	0	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	0	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	81000	USD
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	4023000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	2840000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	39640000	USD
CY2019Q4	bhlb	Impaired Financing Receivable Additional Funds Committed Amount ImpairedFinancingReceivableAdditionalFundsCommittedAmount	0	USD
CY2018Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	27415000	USD
CY2017Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	41990000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	6086000	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	8547000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Other Increase Decrease FinancingReceivableTroubledDebtRestructuringOtherIncreaseDecrease	-4076000	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Other Increase Decrease FinancingReceivableTroubledDebtRestructuringOtherIncreaseDecrease	-8713000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	2063000	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	2685000	USD
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	19316000	USD
CY2018Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	27415000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	199194000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	200437000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	86531000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	78966000	USD
CY2020	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	12500000	USD
CY2019	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	11800000	USD
CY2018	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	10800000	USD
CY2020	bhlb	Business Acquisition Number Of Significant Acquisitions Completed BusinessAcquisitionNumberOfSignificantAcquisitionsCompleted	0	acquisition
CY2019Q4	us-gaap	Goodwill Goodwill	553762000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	518325000	USD
CY2020	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	0	USD
CY2019	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	942000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	553762000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Goodwill Goodwill	0	USD
CY2019Q4	us-gaap	Goodwill Goodwill	553762000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	92637000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	57818000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	34819000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	100327000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	54712000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	45615000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6200000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5800000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4900000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	5300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	5100000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	4800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	4600000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	4500000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	10600000	USD
CY2019	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2020	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2018	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16348000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	26451000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	46919000	USD
CY2019Q4	us-gaap	Interest Receivable InterestReceivable	36462000	USD
CY2020Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	40751000	USD
CY2019Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	23786000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	60018000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	76332000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	160071000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	80190000	USD
CY2020Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	46370000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	51165000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	16753000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	18381000	USD
CY2020Q4	us-gaap	Other Assets OtherAssets	387230000	USD
CY2019Q4	us-gaap	Other Assets OtherAssets	312767000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	26451000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	23376000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	3875000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	16837000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3761000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3240000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Other Changes That Affect Balance Amount ServicingAssetAtAmortizedValueOtherChangesThatAffectBalanceAmount	9266000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Other Changes That Affect Balance Amount ServicingAssetAtAmortizedValueOtherChangesThatAffectBalanceAmount	5822000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	-951000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	-4700000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16348000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	26451000	USD
CY2020Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	3000000.0	USD
CY2019Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	12300000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	1582492000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	2734870000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	545100000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	582622000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	171810000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	145976000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	32358000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	90731000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	51073000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	33754000	USD
CY2020Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	2252000	USD
CY2019Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	1416000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	2385085000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	3589369000	USD
CY2020Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	663324000	USD
CY2019Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	905190000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	1219210000	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	2027717000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	502551000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	656462000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	2385085000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	3589369000	USD
CY2020Q4	bhlb	Brokered Time Deposits BrokeredTimeDeposits	600000000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	40000000	USD
CY2019Q4	bhlb	Brokered Time Deposits BrokeredTimeDeposits	1200000000	USD
CY2020Q4	bhlb	Reciprocal Money Market Deposits ReciprocalMoneyMarketDeposits	119000000.0	USD
CY2019Q4	bhlb	Reciprocal Money Market Deposits ReciprocalMoneyMarketDeposits	91700000	USD
CY2020Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0105
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	125000000	USD
CY2019Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0206
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	531637000	USD
CY2020Q4	us-gaap	Longterm Debt Weighted Average Interest Rate LongtermDebtWeightedAverageInterestRate	0.0261
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	702550000	USD
CY2019Q4	us-gaap	Longterm Debt Weighted Average Interest Rate LongtermDebtWeightedAverageInterestRate	0.0272
CY2020Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	571637000	USD
CY2020Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0250
CY2019Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	827550000	USD
CY2019Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0262
CY2020Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	474357000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	0	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	0	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	65758000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	80681000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10383000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10883000	USD
CY2020Q4	us-gaap	Other Payables To Broker Dealers And Clearing Organizations OtherPayablesToBrokerDealersAndClearingOrganizations	0	USD
CY2019Q4	us-gaap	Other Payables To Broker Dealers And Clearing Organizations OtherPayablesToBrokerDealersAndClearingOrganizations	189000	USD
CY2020Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	38830000	USD
CY2019Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	44781000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	63894000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80734000	USD
CY2020Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	3867000	USD
CY2019Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	11625000	USD
CY2020Q4	bhlb	Customer Transaction Clearing Accounts Payable CustomerTransactionClearingAccountsPayable	11261000	USD
CY2019Q4	bhlb	Customer Transaction Clearing Accounts Payable CustomerTransactionClearingAccountsPayable	4310000	USD
CY2020Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	38737000	USD
CY2019Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	60676000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3500000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4100000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3900000	USD
CY2020Q4	bhlb	Postemployment Benefits Liability Split Dollar Agreement PostemploymentBenefitsLiabilitySplitDollarAgreement	7900000	USD
CY2019Q4	bhlb	Postemployment Benefits Liability Split Dollar Agreement PostemploymentBenefitsLiabilitySplitDollarAgreement	7100000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-19889000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	16576000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	12634000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-3976000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	5323000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	4114000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-23865000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	21899000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16748000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	2048000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	908000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	8443000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1964000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-344000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3770000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4012000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	564000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	12213000	USD
CY2020	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	0	USD
CY2019	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	0	USD
CY2018	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	0	USD
CY2020Q4	bhlb	Current Income Tax Expense Benefit Net Operating Loss Cares Act CurrentIncomeTaxExpenseBenefitNetOperatingLossCARESAct	6000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	35650000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	17446000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	2360000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	6195000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	7607000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	10565000	USD
CY2020Q4	bhlb	Deferred Tax Assets Purchase Accounting Adjustments DeferredTaxAssetsPurchaseAccountingAdjustments	8843000	USD
CY2019Q4	bhlb	Deferred Tax Assets Purchase Accounting Adjustments DeferredTaxAssetsPurchaseAccountingAdjustments	39359000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1753000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	951000	USD
CY2020Q4	bhlb	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	20119000	USD
CY2019Q4	bhlb	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	22497000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	1097000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	739000	USD
CY2020Q4	bhlb	Deferred Tax Asset Nonaccrual Interest DeferredTaxAssetNonaccrualInterest	1780000	USD
CY2019Q4	bhlb	Deferred Tax Asset Nonaccrual Interest DeferredTaxAssetNonaccrualInterest	587000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1733000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	501000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	80942000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	98840000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	46370000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	47747000	USD
CY2020	bhlb	Deferred Tax Assets Liabilities Net Increase Decrease DeferredTaxAssetsLiabilitiesNetIncreaseDecrease	1400000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	80742000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	98640000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	10602000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	4244000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	1674000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	4669000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Financing Costs DeferredTaxLiabilitiesDeferredExpenseDeferredFinancingCosts	368000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Financing Costs DeferredTaxLiabilitiesDeferredExpenseDeferredFinancingCosts	1667000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	2277000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	18557000	USD
CY2020Q4	bhlb	Deferred Tax Liabilities Unamortized Tax Credit Reserve DeferredTaxLiabilitiesUnamortizedTaxCreditReserve	1086000	USD
CY2019Q4	bhlb	Deferred Tax Liabilities Unamortized Tax Credit Reserve DeferredTaxLiabilitiesUnamortizedTaxCreditReserve	1142000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	18365000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	20614000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	34372000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	50893000	USD
CY2020Q4	bhlb	State Tax Basis Difference Net Of Federal Tax Benefit StateTaxBasisDifferenceNetOfFederalTaxBenefit	200000	USD
CY2019Q4	bhlb	State Tax Basis Difference Net Of Federal Tax Benefit StateTaxBasisDifferenceNetOfFederalTaxBenefit	200000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	1000000.0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	803000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	238000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	467000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	304000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	309000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	26000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	533000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	370000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	185000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	31000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	70000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	516000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	238000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	467000	USD
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3900000000	USD
CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	75100000	USD
CY2020Q4	bhlb	Derivative Securities Pledged As Collateral Amortized Cost DerivativeSecuritiesPledgedAsCollateralAmortizedCost	37500000	USD
CY2020Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	37800000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	96300000	USD
CY2019Q4	bhlb	Derivative Securities Pledged As Collateral Amortized Cost DerivativeSecuritiesPledgedAsCollateralAmortizedCost	25700000	USD
CY2019Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	25800000	USD
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3857115000	USD
CY2020Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	94313000	USD
CY2019Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	4070729000	USD
CY2019Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	-492000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	60018000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	76332000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	7197000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	7720000	USD
CY2020Q4	bhlb	Lease Rightof Use Asset LeaseRightofUseAsset	67215000	USD
CY2019Q4	bhlb	Lease Rightof Use Asset LeaseRightofUseAsset	84052000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	63894000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80734000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10383000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10883000	USD
CY2020Q4	bhlb	Lease Liability LeaseLiability	74277000	USD
CY2019Q4	bhlb	Lease Liability LeaseLiability	91617000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y9M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y3M18D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P13Y9M18D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P14Y9M18D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0281
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0336
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0500
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0500
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	13500000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	14400000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	13750000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	14731000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	530000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	553000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	500000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	435000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7083000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	88079000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2019Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	2000000.0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	10875000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	1023000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	9990000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1031000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	8752000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1037000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	7508000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	1037000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	5668000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	1037000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	31215000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	9223000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	74008000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	14388000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	10114000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	4005000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	63894000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10383000	USD
	bhlb	Financing Receivable Modifications Numberof Contracts Modifiedunder Interagencyguidanceand Cares Act FinancingReceivableModificationsNumberofContractsModifiedunderInteragencyguidanceandCARESAct	5701	Loan
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CY2020Q4	bhlb	Financing Receivable Modifications Active Modified Loans FinancingReceivableModificationsActiveModifiedLoans	746	Loan
CY2020Q4	bhlb	Financing Receivable Modifications Active Modified Loans Carrying Value FinancingReceivableModificationsActiveModifiedLoansCarryingValue	316100000	USD
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1778480000	USD
CY2019Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1835422000	USD
CY2020Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	110000	USD
CY2020Q4	us-gaap	Capital Capital	1337008000	USD
CY2020Q4	us-gaap	Capital To Risk Weighted Assets CapitalToRiskWeightedAssets	0.1610
CY2020Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	664239000	USD
CY2020Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0800
CY2020Q4	bhlb	Common Equity Tier One Risk Based Capitalto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitaltoRiskWeightedAssetsAmount	1145329000	USD
CY2020Q4	bhlb	Common Equity Tier One Risk Based Capital To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets	0.1379
CY2020Q4	bhlb	Common Equity Tier One Risk Based Capital Requiredtobe Well Capitalizedto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitalRequiredtobeWellCapitalizedtoRiskWeightedAssetsAmount	373634000	USD
CY2020Q4	bhlb	Common Equity Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets	0.0450
CY2020Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	1167512000	USD
CY2020Q4	us-gaap	Tier One Risk Based Capital To Risk Weighted Assets TierOneRiskBasedCapitalToRiskWeightedAssets	0.1406
CY2020Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	498179000	USD
CY2020Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0600
CY2020Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	1167512000	USD
CY2020Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.0938
CY2020Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	332119000	USD
CY2020Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy To Average Assets TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets	0.0400
CY2019Q4	us-gaap	Capital Capital	1321910000	USD
CY2019Q4	us-gaap	Capital To Risk Weighted Assets CapitalToRiskWeightedAssets	0.1373
CY2019Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	770294000	USD
CY2019Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0800
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capitalto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitaltoRiskWeightedAssetsAmount	1161800000	USD
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capital To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets	0.1207
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capital Requiredtobe Well Capitalizedto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitalRequiredtobeWellCapitalizedtoRiskWeightedAssetsAmount	433290000	USD
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets	0.0450
CY2019Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	1183932000	USD
CY2019Q4	us-gaap	Tier One Risk Based Capital To Risk Weighted Assets TierOneRiskBasedCapitalToRiskWeightedAssets	0.1230
CY2019Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	577720000	USD
CY2019Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0600
CY2019Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	1183932000	USD
CY2019Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.0933
CY2019Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	385147000	USD
CY2018	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	421000	shares
CY2019Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy To Average Assets TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets	0.0400
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	25237000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	6359000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	18878000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	34260000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	8797000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2019	bhlb	Total Change To Aoci Before Tax Attributable To Parent TotalChangeToAOCIBeforeTaxAttributableToParent	34260000	USD
CY2019	bhlb	Total Change To Aoci Tax Attributable To Parent TotalChangeToAOCITaxAttributableToParent	8797000	USD
CY2019	bhlb	Total Change To Aoci Net Of Tax Attributable To Parent TotalChangeToAOCINetOfTaxAttributableToParent	25463000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-16587000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-4313000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2018	bhlb	Total Change To Aoci Before Tax Attributable To Parent TotalChangeToAOCIBeforeTaxAttributableToParent	-24966000	USD
CY2018	bhlb	Total Change To Aoci Tax Attributable To Parent TotalChangeToAOCITaxAttributableToParent	-7335000	USD
CY2018	bhlb	Total Change To Aoci Net Of Tax Attributable To Parent TotalChangeToAOCINetOfTaxAttributableToParent	-17631000	USD
CY2020	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	18874000	USD
CY2020	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-4000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	18878000	USD
CY2019	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	25507000	USD
CY2019	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	44000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2018	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-12417000	USD
CY2018	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-143000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	109219000	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-19842000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-3454000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	51903000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	49782000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	46212000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	1569000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	1142000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	810000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	505000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	420000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46024000	shares
CY2020	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	441000	shares
CY2019	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	1043000	shares
CY2018	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	1043000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50270000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49263000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50270000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49421000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46231000	shares
CY2020	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	-10.21
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.06
CY2018	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.38
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.39
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.08
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.08
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-10.60
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.30
CY2020	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	-10.21
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.05
CY2018	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.36
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.39
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.08
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.07
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-10.60
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.97
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.29
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	34807000	USD
CY2020	bhlb	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 Number Of Transfers FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3NumberOfTransfers	4	transfer
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	44000000.0	USD
CY2019	bhlb	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 Number Of Transfers FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3NumberOfTransfers	0	transfer
CY2020Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	92131000	USD
CY2020Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	97768000	USD
CY2020Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	103688000	USD
CY2020Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	116195000	USD
CY2019Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	125441000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	133725000	USD
CY2019Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	129238000	USD
CY2019Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	121109000	USD
CY2020Q4	us-gaap	Interest Expense InterestExpense	16422000	USD
CY2020Q3	us-gaap	Interest Expense InterestExpense	20713000	USD
CY2020Q2	us-gaap	Interest Expense InterestExpense	26098000	USD
CY2020Q1	us-gaap	Interest Expense InterestExpense	29767000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	34108000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	36854000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	37643000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	35650000	USD
CY2020Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	75709000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	77055000	USD
CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	77590000	USD
CY2020Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	29871000	USD
CY2020Q1	us-gaap	Revenues Revenues	92064000	USD
CY2019Q4	us-gaap	Revenues Revenues	114695000	USD
CY2019Q3	us-gaap	Revenues Revenues	118277000	USD
CY2019Q2	us-gaap	Revenues Revenues	109107000	USD
CY2019Q1	us-gaap	Revenues Revenues	107181000	USD
CY2020Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	10000000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1200000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	86428000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91333000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	96871000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91595000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	85459000	USD
CY2020Q4	us-gaap	Noninterest Income NoninterestIncome	23327000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	19963000	USD
CY2020Q2	us-gaap	Noninterest Income NoninterestIncome	17381000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	5636000	USD
CY2019Q4	us-gaap	Noninterest Income NoninterestIncome	23362000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	21406000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	17512000	USD
CY2019Q1	us-gaap	Noninterest Income NoninterestIncome	21722000	USD
CY2020Q4	us-gaap	Revenues Revenues	99036000	USD
CY2020Q3	us-gaap	Revenues Revenues	97018000	USD
CY2020Q2	us-gaap	Revenues Revenues	94971000	USD
CY2019Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	5351000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	22600000	USD
CY2019Q1	us-gaap	Noninterest Expense NoninterestExpense	71991000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	17240000	USD
CY2019Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3467000	USD
CY2019Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	4001000	USD
CY2020Q4	us-gaap	Noninterest Expense NoninterestExpense	71796000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	72843000	USD
CY2020Q2	us-gaap	Noninterest Expense NoninterestExpense	624275000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	71325000	USD
CY2019Q4	us-gaap	Noninterest Expense NoninterestExpense	70287000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	71011000	USD
CY2019Q2	us-gaap	Noninterest Expense NoninterestExpense	76568000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	22975000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-559175000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-14068000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	39057000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	24666000	USD
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	1494000	USD
CY2019Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-637000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	15009000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	21225000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-549381000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	-19870000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	25751000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	22616000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	25448000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	23635000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.38
CY2020Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.46
CY2020Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	-10.80
CY2020Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-1818000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	29072000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	31189000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	18899000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	23043000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-543045000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-12072000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	32636000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	20659000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	23954000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	24272000	USD
CY2020Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-3890000	USD
CY2020Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-6336000	USD
CY2020Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-7798000	USD
CY2019Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-6885000	USD
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	1957000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	-0.24
CY2019Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.65
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.40
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.49
CY2019Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.52
CY2020Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.08
CY2020Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.04
CY2020Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.13
CY2020Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.16
CY2019Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.14
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.04
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.03
CY2019Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.01
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.30
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.42
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-10.93
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.40
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.51
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.44
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.52
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.51
CY2020Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.38
CY2020Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.46
CY2020Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	-10.80
CY2020Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	-0.24
CY2019Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.65
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.40
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.49
CY2019Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.52
CY2020Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.08
CY2020Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.04
CY2020Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.13
CY2020Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.16
CY2019Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.14
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.04
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.03
CY2019Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.01
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.30
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.42
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-10.93
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.40
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.44
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.52
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2020Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50308000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50329000	shares
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50246000	shares
CY2020Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50204000	shares
CY2019Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50494000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51422000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	48961000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46113000	shares
CY2020Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50355000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50329000	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50246000	shares
CY2020Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50204000	shares
CY2019Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50702000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51545000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49114000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46261000	shares
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	316782000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	365258000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	356200000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	75878000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	35419000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25451000	USD
CY2020	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	240904000	USD
CY2019	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	329839000	USD
CY2018	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	330749000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	66307000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	74324000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	840239000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	289857000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	266893000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-533028000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	123984000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	138180000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	109219000	USD
CY2020	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-26855000	USD
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-5539000	USD
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-4767000	USD
CY2020	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-7013000	USD
CY2019	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1468000	USD
CY2018	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1313000	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-19842000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-3454000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	46853000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	49698000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	48653000	USD
CY2020	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	19454000	USD
CY2019	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	34304000	USD
CY2018	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	25671000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	66307000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	74324000	USD

Files In Submission

Name	View Source	Status
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0001108134-21-000007-index.html	Edgar Link	pending
0001108134-21-000007.txt	Edgar Link	pending
0001108134-21-000007-xbrl.zip	Edgar Link	pending
bhlb-20201231.htm	Edgar Link	pending
bhlb-20201231.xsd	Edgar Link	pending
bhlb-20201231_cal.xml	Edgar Link	unprocessable
bhlb-20201231_def.xml	Edgar Link	unprocessable
bhlb-20201231_g1.jpg	Edgar Link	pending
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$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb

2019 Q4 Form 10-K Financial Statement

#000110813421000007 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BHLB BERKSHIRE HILLS BANCORP INC Stock $bhlb

2019 Q4 Form 10-K Financial Statement

#000110813421000007 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb