$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb

$bhlb Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000110813422000004 Filed on March 01, 2022

Income Statement

Concept	2021 Q4	2021 Q3	2021 Q2
Revenue	$90.72M	$145.0M	$97.40M
YoY Change	-8.4%	49.46%	2.56%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$8.397M	$8.214M
YoY Change		-1.67%	5.92%
% of Gross Profit
Depreciation & Amortization	$3.900M	$4.100M	$4.100M
YoY Change	-13.33%	-10.87%	-12.77%
% of Gross Profit
Operating Expenses		$8.397M	$8.214M
YoY Change		-1.67%	5.92%
Operating Profit
YoY Change
Interest Expense	$6.548M	$8.320M	$9.971M
YoY Change	-60.13%	-59.83%	-61.79%
% of Operating Profit
Other Income/Expense, Net		$1.279M	$2.211M
YoY Change		-33.63%	-321.32%
Pretax Income	$24.31M	$79.54M	$28.53M
YoY Change	41.03%	246.22%	-105.1%
Income Tax	$4.066M	$15.79M	$6.896M
% Of Pretax Income	16.72%	19.86%	24.17%
Net Earnings	$20.25M	$63.75M	$21.64M
YoY Change	34.91%	200.35%	-103.94%
Net Earnings / Revenue	22.32%	43.96%	22.21%
Basic Earnings Per Share	$0.42	$1.32	$0.43
Diluted Earnings Per Share	$0.42	$1.31	$0.43
COMMON SHARES
Basic Shares Outstanding	47.96M shares	48.40M shares	50.32M shares
Diluted Shares Outstanding	48.34M shares	48.74M shares	50.61M shares

Balance Sheet

Concept	2021 Q4	2021 Q3	2021 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.643B	$2.140B	$1.842B
YoY Change	4.24%	121.25%	71.0%
Cash & Equivalents	$1.628B	$2.125B	$1.827B
Short-Term Investments	$15.45M	$15.60M	$15.71M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$94.38M	$99.23M	$104.7M
YoY Change	-16.23%	-15.27%	-11.83%
Goodwill	$0.00
YoY Change
Intangibles	$29.62M	$30.91M	$32.20M
YoY Change	-14.93%	-24.52%	-24.19%
Long-Term Investments
YoY Change
Other Assets	$57.00M	$4.000M	$277.0M
YoY Change	-82.02%	-69.23%	1159.09%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$11.55B	$11.85B	$12.27B
YoY Change	-9.99%	-6.09%	-6.05%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$56.00M	$57.00M	$61.00M
YoY Change	-12.5%	-25.0%	-22.78%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change	-100.0%	-100.0%	-100.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$56.00M	$57.00M	$61.00M
YoY Change	-12.5%	-25.0%	-22.78%
LONG-TERM LIABILITIES
Long-Term Debt	$107.0M	$107.0M	$108.0M
YoY Change	-0.93%	-0.93%	0.0%
Other Long-Term Liabilities	$127.0M	$124.0M	$797.0M
YoY Change	-83.9%	-30.73%	267.28%
Total Long-Term Liabilities	$234.0M	$231.0M	$905.0M
YoY Change	-73.91%	-19.51%	178.46%
TOTAL LIABILITIES
Total Short-Term Liabilities	$56.00M	$57.00M	$61.00M
Total Long-Term Liabilities	$234.0M	$231.0M	$905.0M
Total Liabilities	$10.37B	$10.67B	$11.10B
YoY Change	-10.97%	-6.71%	-6.73%
SHAREHOLDERS EQUITY
Retained Earnings	-$139.4M	-$153.4M	-$211.0M
YoY Change	-40.27%	-36.64%	-18.01%
Common Stock	$1.424B	$1.424B	$1.424B
YoY Change	-0.27%	0.07%	-0.32%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$89.86M	$90.15M	$40.99M
YoY Change	187.3%	92.42%	-21.2%
Treasury Stock Shares	3.236M shares	3.246M shares	1.450M shares
Shareholders Equity	$1.182B	$1.178B	$1.175B
YoY Change
Total Liabilities & Shareholders Equity	$11.55B	$11.85B	$12.27B
YoY Change	-9.99%	-6.09%	-6.05%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2021 Q2
OPERATING ACTIVITIES
Net Income	$20.25M	$63.75M	$21.64M
YoY Change	34.91%	200.35%	-103.94%
Depreciation, Depletion And Amortization	$3.900M	$4.100M	$4.100M
YoY Change	-13.33%	-10.87%	-12.77%
Cash From Operating Activities	$23.00M	$18.80M	$40.10M
YoY Change	-29.88%	6.82%	-71.78%
INVESTING ACTIVITIES
Capital Expenditures	$0.00	$0.00	$700.0K
YoY Change	-100.0%	-100.0%	-163.64%
Acquisitions
YoY Change
Other Investing Activities	-$227.5M	$83.00M	$391.3M
YoY Change	-165.04%	-73.29%	-322.33%
Cash From Investing Activities	-$227.5M	$83.00M	$392.0M
YoY Change	-165.22%	-73.15%	-321.34%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-292.1M	196.1M	-505.2M
YoY Change	-221.25%	-145.02%	-206.63%
NET CHANGE
Cash From Operating Activities	23.00M	18.80M	40.10M
Cash From Investing Activities	-227.5M	83.00M	392.0M
Cash From Financing Activities	-292.1M	196.1M	-505.2M
Net Change In Cash	-496.6M	297.9M	-73.10M
YoY Change	-179.78%	-373.55%	-116.66%
FREE CASH FLOW
Cash From Operating Activities	$23.00M	$18.80M	$40.10M
Capital Expenditures	$0.00	$0.00	$700.0K
Free Cash Flow	$23.00M	$18.80M	$39.40M
YoY Change	-31.95%	-2.59%	-72.49%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021	dei	Entity Registrant Name EntityRegistrantName	BERKSHIRE HILLS BANCORP, INC.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
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CY2019	us-gaap	Noninterest Income Other NoninterestIncomeOther	1438000	USD
CY2021	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-787000	USD
CY2020	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-7520000	USD
CY2019	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	4389000	USD
CY2021	bhlb	Gain Loss On Disposition Of Business And Other Assets GainLossOnDispositionOfBusinessAndOtherAssets	52942000	USD
CY2020	bhlb	Gain Loss On Disposition Of Business And Other Assets GainLossOnDispositionOfBusinessAndOtherAssets	1240000	USD
CY2019	bhlb	Gain Loss On Disposition Of Business And Other Assets GainLossOnDispositionOfBusinessAndOtherAssets	1351000	USD
CY2021	us-gaap	Noninterest Income NoninterestIncome	143248000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	66307000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD
CY2021	us-gaap	Revenues Revenues	434414000	USD
CY2020	us-gaap	Revenues Revenues	383089000	USD
CY2019	us-gaap	Revenues Revenues	449260000	USD
CY2021	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-500000	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
CY2021	us-gaap	Labor And Related Expense LaborAndRelatedExpense	150589000	USD
CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	147840000	USD
CY2019	us-gaap	Labor And Related Expense LaborAndRelatedExpense	140906000	USD
CY2021	bhlb	Occupancy And Equipment OccupancyAndEquipment	41782000	USD
CY2020	us-gaap	Adjustment For Amortization AdjustmentForAmortization	6181000	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	5876000	USD
CY2019	bhlb	Occupancy And Equipment OccupancyAndEquipment	39586000	USD
CY2021	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	33803000	USD
CY2020	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	32364000	USD
CY2019	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	26523000	USD
CY2021	us-gaap	Marketing Expense MarketingExpense	2749000	USD
CY2020	us-gaap	Marketing Expense MarketingExpense	3703000	USD
CY2019	us-gaap	Marketing Expense MarketingExpense	4474000	USD
CY2021	us-gaap	Professional Fees ProfessionalFees	15860000	USD
CY2020	us-gaap	Professional Fees ProfessionalFees	11907000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	10798000	USD
CY2021	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3759000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3861000	USD
CY2021	bhlb	Other Real Estate Owned OtherRealEstateOwned	17000	USD
CY2020	bhlb	Other Real Estate Owned OtherRealEstateOwned	125000	USD
CY2019	bhlb	Other Real Estate Owned OtherRealEstateOwned	154000	USD
CY2021	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5200000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5783000	USD
CY2021	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	553762000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2021	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	5781000	USD
CY2020	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	5839000	USD
CY2019	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	28046000	USD
CY2021	us-gaap	Other Noninterest Expense OtherNoninterestExpense	26353000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	29283000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	29726000	USD
CY2021	us-gaap	Noninterest Expense NoninterestExpense	285893000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	840239000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	289857000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	149021000	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
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	30357000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19853000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2021	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	118664000	USD
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	101521000	USD
CY2021	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	0	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
CY2021	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	0	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
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	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
CY2021	us-gaap	Net Income Loss NetIncomeLoss	118664000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	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
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	118664000	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
CY2021	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.41
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
CY2021	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
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
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.41
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-10.60
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.92
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
CY2021	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.39
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
CY2021	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0
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
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.39
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-10.60
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.97
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49240000	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
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49554000	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
CY2021	us-gaap	Net Income Loss NetIncomeLoss	118664000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-46794000	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
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-993000	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
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-45801000	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
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-11937000	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
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-250000	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
CY2021	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-11687000	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
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-34114000	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
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	84550000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-514139000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	122913000	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	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
CY2021	us-gaap	Net Income Loss NetIncomeLoss	118664000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-34114000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	84550000	USD
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.48
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	24553000	USD
CY2021	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	68712000	USD
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	USD
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4170000	USD
CY2021	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	417000	USD
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2021	us-gaap	Stockholders Equity Other StockholdersEquityOther	1210000	USD
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	1182435000	USD
CY2021	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	118664000	USD
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	101521000	USD
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	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
CY2021	us-gaap	Net Income Loss NetIncomeLoss	118664000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2021	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-500000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	75878000	USD
CY2021	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5200000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	35419000	USD
CY2021	bhlb	Amortization Of Securities AmortizationOfSecurities	1939000	USD
CY2020	bhlb	Amortization Of Securities AmortizationOfSecurities	2513000	USD
CY2019	bhlb	Amortization Of Securities AmortizationOfSecurities	2407000	USD
CY2021	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	1918000	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
CY2021	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	11035000	USD
CY2020	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	11919000	USD
CY2019	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	10921000	USD
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	4170000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	4727000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	4812000	USD
CY2021	bhlb	Accretion Of Purchase Accounting Entries AccretionOfPurchaseAccountingEntries	-6577000	USD
CY2020	bhlb	Accretion Of Purchase Accounting Entries AccretionOfPurchaseAccountingEntries	-10377000	USD
CY2019	bhlb	Accretion Of Purchase Accounting Entries AccretionOfPurchaseAccountingEntries	-14813000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-5000	USD
CY2019	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	4389000	USD
CY2020	us-gaap	Adjustment For Amortization AdjustmentForAmortization	6181000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5783000	USD
CY2021	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	5561000	USD
CY2020	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	5354000	USD
CY2019	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	5349000	USD
CY2021	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	-787000	USD
CY2020	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	-7576000	USD
CY2021	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	-5775000	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
CY2021	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-2811000	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
CY2021	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-6000	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-13000	USD
CY2021	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	3444000	USD
CY2020	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	3645000	USD
CY2019	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	6455000	USD
CY2021	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	553762000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2021	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	52942000	USD
CY2020	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2021	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Repayment And Penalties FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresRepaymentAndPenalties	862000	USD
CY2020	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Repayment And Penalties FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresRepaymentAndPenalties	0	USD
CY2019	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Repayment And Penalties FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresRepaymentAndPenalties	0	USD
CY2021	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-18282000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	31247000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	23418000	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	105477000	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
CY2021	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	0	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
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	105477000	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
CY2021	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-776000	USD
CY2020	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-734000	USD
CY2019	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-701000	USD
CY2021	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	0	USD
CY2020	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	17631000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	23841000	USD
CY2021	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	2880000	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
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	804616000	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
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	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
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	575538000	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
CY2021	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	219470000	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
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	46061000	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
CY2021	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-1262521000	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
CY2021	bhlb	Increase Decrease In Loans Held For Sale Investing Activities IncreaseDecreaseInLoansHeldForSaleInvestingActivities	-50914000	USD
CY2020	bhlb	Increase Decrease In Loans Held For Sale Investing Activities IncreaseDecreaseInLoansHeldForSaleInvestingActivities	0	USD
CY2019	bhlb	Increase Decrease In Loans Held For Sale Investing Activities IncreaseDecreaseInLoansHeldForSaleInvestingActivities	0	USD
CY2021	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	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
CY2021	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2566000	USD
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	553000	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2451000	USD
CY2021	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	0	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
CY2021	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	24078000	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
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	2878000	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
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1606000	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
CY2021	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	16417000	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
CY2021	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	187000	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
CY2021	bhlb	Payments For Disposal Of Business Settlement Amount PaymentsForDisposalOfBusinessSettlementAmount	352814000	USD
CY2020	bhlb	Payments For Disposal Of Business Settlement Amount PaymentsForDisposalOfBusinessSettlementAmount	0	USD
CY2019	bhlb	Payments For Disposal Of Business Settlement Amount PaymentsForDisposalOfBusinessSettlementAmount	0	USD
CY2021	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	0	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
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	600554000	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
CY2021	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-154052000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	499657000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	23996000	USD
CY2021	bhlb	Increase Decrease In Loans Held For Sale Financing Activities IncreaseDecreaseInLoansHeldForSaleFinancingActivities	-20953000	USD
CY2020	bhlb	Increase Decrease In Loans Held For Sale Financing Activities IncreaseDecreaseInLoansHeldForSaleFinancingActivities	0	USD
CY2019	bhlb	Increase Decrease In Loans Held For Sale Financing Activities IncreaseDecreaseInLoansHeldForSaleFinancingActivities	0	USD
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	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
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	45107000	USD
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	462059000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	582648000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	6228780000	USD
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	68712000	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
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	417000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	664000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	188000	USD
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	24553000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	36564000	USD
CY2021	bhlb	Settlementof Derivative Contractswith Institutional Counterparties SettlementofDerivativeContractswithInstitutionalCounterparties	-51907000	USD
CY2020	bhlb	Settlementof Derivative Contractswith Institutional Counterparties SettlementofDerivativeContractswithInstitutionalCounterparties	97611000	USD
CY2019	bhlb	Settlementof Derivative Contractswith Institutional Counterparties SettlementofDerivativeContractswithInstitutionalCounterparties	0	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-636099000	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
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	69932000	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
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
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1627807000	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
CY2021	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	29606000	USD
CY2020	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	82319000	USD
CY2019	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	119695000	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	11385000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	21277000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	33406000	USD
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	14816000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-13864000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	19818000	USD
CY2021	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	0	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
CY2021	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	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
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-34114000	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
CY2021	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	11660000	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
CY2021	bhlb	Noncash Investing And Financing Activities Reclassification Of Premises And Equipment To Held For Sale NoncashInvestingAndFinancingActivitiesReclassificationOfPremisesAndEquipmentToHeldForSale	4577000	USD
CY2020	bhlb	Noncash Investing And Financing Activities Reclassification Of Premises And Equipment To Held For Sale NoncashInvestingAndFinancingActivitiesReclassificationOfPremisesAndEquipmentToHeldForSale	0	USD
CY2019	bhlb	Noncash Investing And Financing Activities Reclassification Of Premises And Equipment To Held For Sale NoncashInvestingAndFinancingActivitiesReclassificationOfPremisesAndEquipmentToHeldForSale	0	USD
CY2021	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	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
CY2021	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>
CY2021	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:120%">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:120%">Refer to Note 18 – Other Commitments, Contingencies, and Off-Balance Sheet Activities for pandemic related risks and uncertainties.</span></div>
CY2021	bhlb	Threshold Period Past Due For Financing Receivable Excluding Automobile Loans Not Accrue Interest ThresholdPeriodPastDueForFinancingReceivableExcludingAutomobileLoansNotAccrueInterest	P90D
CY2021	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:120%">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:120%">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:120%">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:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%;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:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%;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:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%;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:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%;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:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%;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:120%">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 style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%">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><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:120%">Construction</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%"> – 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:120%">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:120%"> – 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:120%">Commercial and industrial loans</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%"> – 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:120%">Residential real estate</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:11pt;font-weight:400;line-height:120%"> – 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:120%">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:120%"> – 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:120%">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 certain 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>
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CY2020Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	8700000	USD
CY2021Q4	us-gaap	Trading Securities TradingSecurities	8400000	USD
CY2020Q4	us-gaap	Trading Securities TradingSecurities	9700000	USD
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CY2020	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	-300000	USD
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CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	USD
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CY2021Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	9008000	USD
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CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	-442000	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
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	14528000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	712488000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	7868000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	252279000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	22396000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	964767000	USD
CY2021Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	4610000	USD
CY2021Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	194606000	USD
CY2021Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	4398000	USD
CY2021Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	113891000	USD
CY2021Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	9008000	USD
CY2021Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	308497000	USD
CY2021Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLosses	19138000	USD
CY2021Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan Twelve Months Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue	907094000	USD
CY2021Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLosses	12266000	USD
CY2021Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Twelve Monthsor Longer Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue	366170000	USD
CY2021Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses	31404000	USD
CY2021Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionFairValue	1273264000	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
CY2021Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	6825847000	USD
CY2020Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	8081519000	USD
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	106094000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	127302000	USD
CY2021Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	6719753000	USD
CY2020Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	7954217000	USD
CY2021	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	211000000	USD
CY2021	us-gaap	Proceeds From Sale Of Loans And Leases Held For Investment ProceedsFromSaleOfLoansAndLeasesHeldForInvestment	560000000	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
CY2021	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	20700000	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	USD
CY2021Q4	us-gaap	Loans Pledged As Collateral LoansPledgedAsCollateral	700000000	USD
CY2021Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	1700000	USD
CY2020Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	2000000	USD
CY2021Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	1000000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	1100000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	127302000	USD
CY2021	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	31018000	USD
CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	10311000	USD
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-501000	USD
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	106094000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	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 Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	127302000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	7629000	USD
CY2021	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-586000	USD
CY2021Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	7043000	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
CY2021Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	6825847000	USD
CY2020Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	8081519000	USD
CY2021Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	35326000	USD
CY2021Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	19174000	USD
CY2021Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	3271000	USD
CY2021Q4	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	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
CY2021Q4	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	20548000	USD
CY2021	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	18878000	USD
CY2021	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2021	bhlb	Financing Receivable Troubled Debt Restructuring Other Increase Decrease FinancingReceivableTroubledDebtRestructuringOtherIncreaseDecrease	-1327000	USD
CY2021	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	26759000	USD
CY2021Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	27102000	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
CY2021	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	18000	loan
CY2021	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	26759000	USD
CY2021	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	26759000	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
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	2063000	USD
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	4	loan
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	12197000	USD
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
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	loan
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	4	loan
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	18817000	USD
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	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	2840000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldAdditions	4200000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	9619000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	7430000	USD
CY2020	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Payments Received CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldPaymentsReceived	837000	USD
CY2020	bhlb	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassification To Troubled Debt Restructuring CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationToTroubledDebtRestructuring	9000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	0	USD
CY2020Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	4023000	USD
CY2020Q4	bhlb	Impaired Financing Receivable Additional Funds Committed Amount ImpairedFinancingReceivableAdditionalFundsCommittedAmount	0	USD
CY2018Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	27415000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	6086000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Other Increase Decrease FinancingReceivableTroubledDebtRestructuringOtherIncreaseDecrease	-4076000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	2063000	USD
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	19316000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	183236000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	199194000	USD
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	88853000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	86531000	USD
CY2021	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	11000000	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
CY2021	bhlb	Business Acquisition Number Of Significant Acquisitions Completed BusinessAcquisitionNumberOfSignificantAcquisitionsCompleted	0	acquisition
CY2020	bhlb	Business Acquisition Number Of Significant Acquisitions Completed BusinessAcquisitionNumberOfSignificantAcquisitionsCompleted	0	acquisition
CY2020Q4	us-gaap	Goodwill Goodwill	0	USD
CY2019Q4	us-gaap	Goodwill Goodwill	553762000	USD
CY2021	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	553762000	USD
CY2021Q4	us-gaap	Goodwill Goodwill	0	USD
CY2020Q4	us-gaap	Goodwill Goodwill	0	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	92637000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	63018000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	29619000	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
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5200000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6200000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5800000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	5100000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	4800000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	4600000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	4500000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	4500000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	6000000	USD
CY2020	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2021	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2019	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2021Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16022000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16348000	USD
CY2021Q4	us-gaap	Interest Receivable InterestReceivable	33534000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	46919000	USD
CY2021Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	30614000	USD
CY2020Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	40751000	USD
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	52180000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	60018000	USD
CY2021Q4	us-gaap	Derivative Assets DerivativeAssets	79528000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	160071000	USD
CY2021Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	52620000	USD
CY2020Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	46370000	USD
CY2021Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	23886000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	16753000	USD
CY2021Q4	us-gaap	Other Assets OtherAssets	288384000	USD
CY2020Q4	us-gaap	Other Assets OtherAssets	387230000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16348000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	26451000	USD
CY2021	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	4568000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	3875000	USD
CY2021	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	4921000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3761000	USD
CY2021	us-gaap	Servicing Asset At Amortized Value Other Changes That Affect Balance Amount ServicingAssetAtAmortizedValueOtherChangesThatAffectBalanceAmount	723000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Other Changes That Affect Balance Amount ServicingAssetAtAmortizedValueOtherChangesThatAffectBalanceAmount	9266000	USD
CY2021	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	750000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	-951000	USD
CY2021Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16022000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16348000	USD
CY2021Q4	bhlb	Servicing Asset Portion Reported At Fair Value ServicingAssetPortionReportedAtFairValue	2000000	USD
CY2020Q4	bhlb	Servicing Asset Portion Reported At Fair Value ServicingAssetPortionReportedAtFairValue	3000000	USD
CY2021Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	16600000	USD
CY2020Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	16000000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	1228874000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	1582492000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	280403000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	545100000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	81391000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	171810000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	52000000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	32358000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	34605000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	51073000	USD
CY2021Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	1667000	USD
CY2020Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	2252000	USD
CY2021Q4	us-gaap	Time Deposits TimeDeposits	1678940000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	2385085000	USD
CY2021Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	676979000	USD
CY2020Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	663324000	USD
CY2021Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	610174000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	1219210000	USD
CY2021Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	391787000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	502551000	USD
CY2021Q4	us-gaap	Time Deposits TimeDeposits	1678940000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	2385085000	USD
CY2021Q4	bhlb	Brokered Time Deposits BrokeredTimeDeposits	228100000	USD
CY2020Q4	bhlb	Brokered Time Deposits BrokeredTimeDeposits	610600000	USD
CY2021Q4	bhlb	Reciprocal Money Market Deposits ReciprocalMoneyMarketDeposits	89200000	USD
CY2020Q4	bhlb	Reciprocal Money Market Deposits ReciprocalMoneyMarketDeposits	119000000	USD
CY2021Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	0	USD
CY2021Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	40000000	USD
CY2020Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0105
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	110844000	USD
CY2021Q4	us-gaap	Longterm Debt Weighted Average Interest Rate LongtermDebtWeightedAverageInterestRate	0.0533
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	531637000	USD
CY2020Q4	us-gaap	Longterm Debt Weighted Average Interest Rate LongtermDebtWeightedAverageInterestRate	0.0261
CY2021Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	110844000	USD
CY2021Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0533
CY2020Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	571637000	USD
CY2020Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0250
CY2021Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	13331000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	0	USD
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	0	USD
CY2021Q4	bhlb	Customer Transaction Clearing Accounts Payable CustomerTransactionClearingAccountsPayable	5718000	USD
CY2021Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	35194000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	65758000	USD
CY2021Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	9862000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10383000	USD
CY2021Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	45498000	USD
CY2020Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	38830000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	55674000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	63894000	USD
CY2021Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	775000	USD
CY2020Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	3867000	USD
CY2020Q4	bhlb	Customer Transaction Clearing Accounts Payable CustomerTransactionClearingAccountsPayable	11261000	USD
CY2021Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	39960000	USD
CY2020Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	38737000	USD
CY2021Q4	us-gaap	Other Liabilities OtherLiabilities	192681000	USD
CY2020Q4	us-gaap	Other Liabilities OtherLiabilities	232730000	USD
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3200000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3500000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4100000	USD
CY2021Q4	bhlb	Postemployment Benefits Liability Split Dollar Agreement PostemploymentBenefitsLiabilitySplitDollarAgreement	7800000	USD
CY2020Q4	bhlb	Postemployment Benefits Liability Split Dollar Agreement PostemploymentBenefitsLiabilitySplitDollarAgreement	7900000	USD
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	17340000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-19889000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	16576000	USD
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	7580000	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
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	24920000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-23865000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	21899000	USD
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	5125000	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
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	112000	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
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	5237000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4012000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	564000	USD
CY2021	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	-200000	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
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	30357000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19853000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2021	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	0	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
CY2021	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	30357000	USD
CY2020	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	-26866000	USD
CY2019	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	20995000	USD
CY2020Q4	bhlb	Current Income Tax Expense Benefit Net Operating Loss Cares Act CurrentIncomeTaxExpenseBenefitNetOperatingLossCARESAct	-6000000	USD
CY2021Q4	bhlb	Current Income Tax Expense Benefit Net Operating Loss Cares Act CurrentIncomeTaxExpenseBenefitNetOperatingLossCARESAct	-500000	USD
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	31294000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-111936000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	26037000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6077000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.041
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-1589000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.003
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	3641000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.029
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	3475000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.023
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	3184000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	-0.006
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	3527000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.028
CY2021	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurance	1348000	USD
CY2021	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance Percent EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurancePercent	0.009
CY2020	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurance	1283000	USD
CY2020	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance Percent EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurancePercent	-0.003
CY2019	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurance	1305000	USD
CY2019	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance Percent EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurancePercent	0.011
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	103912000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	-0.195
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0
CY2021	bhlb	Income Tax Reconciliation Disallowed Merger Costs IncomeTaxReconciliationDisallowedMergerCosts	0	USD
CY2021	bhlb	Effective Income Tax Rate Reconciliation Disallowed Merger Costs EffectiveIncomeTaxRateReconciliationDisallowedMergerCosts	0
CY2020	bhlb	Income Tax Reconciliation Disallowed Merger Costs IncomeTaxReconciliationDisallowedMergerCosts	0	USD
CY2020	bhlb	Effective Income Tax Rate Reconciliation Disallowed Merger Costs EffectiveIncomeTaxRateReconciliationDisallowedMergerCosts	0
CY2019	bhlb	Income Tax Reconciliation Disallowed Merger Costs IncomeTaxReconciliationDisallowedMergerCosts	122000	USD
CY2019	bhlb	Effective Income Tax Rate Reconciliation Disallowed Merger Costs EffectiveIncomeTaxRateReconciliationDisallowedMergerCosts	0.001
CY2021	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2881000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.019
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	1812000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	-0.003
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	3531000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.028
CY2021	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	200000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.001
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2021	bhlb	Effective Income Tax Rate Reconciliation Tax Rate Benefit On Net Operating Loss Carryback Amount EffectiveIncomeTaxRateReconciliationTaxRateBenefitOnNetOperatingLossCarrybackAmount	-493000	USD
CY2021	bhlb	Effective Income Tax Rate Reconciliation Tax Rate Benefit On Net Operating Loss Carryback Percent EffectiveIncomeTaxRateReconciliationTaxRateBenefitOnNetOperatingLossCarrybackPercent	-0.003
CY2020	bhlb	Effective Income Tax Rate Reconciliation Tax Rate Benefit On Net Operating Loss Carryback Amount EffectiveIncomeTaxRateReconciliationTaxRateBenefitOnNetOperatingLossCarrybackAmount	-6040000	USD
CY2020	bhlb	Effective Income Tax Rate Reconciliation Tax Rate Benefit On Net Operating Loss Carryback Percent EffectiveIncomeTaxRateReconciliationTaxRateBenefitOnNetOperatingLossCarrybackPercent	0.011
CY2019	bhlb	Effective Income Tax Rate Reconciliation Tax Rate Benefit On Net Operating Loss Carryback Amount EffectiveIncomeTaxRateReconciliationTaxRateBenefitOnNetOperatingLossCarrybackAmount	0	USD
CY2019	bhlb	Effective Income Tax Rate Reconciliation Tax Rate Benefit On Net Operating Loss Carryback Percent EffectiveIncomeTaxRateReconciliationTaxRateBenefitOnNetOperatingLossCarrybackPercent	0
CY2021	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	983000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.006
CY2020	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	2079000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2019	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	1026000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.008
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	30357000	USD
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.204
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19853000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.037
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.181
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	30441000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	35650000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	1451000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	2360000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	1085000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	0	USD
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	8435000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	7607000	USD
CY2021Q4	bhlb	Deferred Tax Assets Purchase Accounting Adjustments DeferredTaxAssetsPurchaseAccountingAdjustments	4829000	USD
CY2020Q4	bhlb	Deferred Tax Assets Purchase Accounting Adjustments DeferredTaxAssetsPurchaseAccountingAdjustments	8843000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1139000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1753000	USD
CY2021Q4	bhlb	Deferred Tax Assets Deferred Loan Fees DeferredTaxAssetsDeferredLoanFees	2449000	USD
CY2020Q4	bhlb	Deferred Tax Assets Deferred Loan Fees DeferredTaxAssetsDeferredLoanFees	0	USD
CY2021Q4	bhlb	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	14940000	USD
CY2020Q4	bhlb	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	20119000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	1850000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	1097000	USD
CY2021Q4	bhlb	Deferred Tax Asset Nonaccrual Interest DeferredTaxAssetNonaccrualInterest	1722000	USD
CY2020Q4	bhlb	Deferred Tax Asset Nonaccrual Interest DeferredTaxAssetNonaccrualInterest	1780000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1845000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1733000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	70186000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	80942000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	400000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	69786000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	80742000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	0	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	10602000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	1488000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	1674000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Financing Costs DeferredTaxLiabilitiesDeferredExpenseDeferredFinancingCosts	0	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Financing Costs DeferredTaxLiabilitiesDeferredExpenseDeferredFinancingCosts	368000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	545000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	2277000	USD
CY2021Q4	bhlb	Deferred Tax Liabilities Unamortized Tax Credit Reserve DeferredTaxLiabilitiesUnamortizedTaxCreditReserve	1075000	USD
CY2020Q4	bhlb	Deferred Tax Liabilities Unamortized Tax Credit Reserve DeferredTaxLiabilitiesUnamortizedTaxCreditReserve	1086000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	14058000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	18365000	USD
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	17166000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	34372000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	52620000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	46370000	USD
CY2021	bhlb	Deferred Tax Assets Liabilities Net Increase Decrease DeferredTaxAssetsLiabilitiesNetIncreaseDecrease	6300000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	400000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2021	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	200000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	527000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	612000	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
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	509000	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
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	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
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	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
CY2021	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	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
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1025000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	516000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	238000	USD
CY2021Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3700000000	USD
CY2021Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	43700000	USD
CY2021Q4	bhlb	Derivative Securities Pledged As Collateral Amortized Cost DerivativeSecuritiesPledgedAsCollateralAmortizedCost	34800000	USD
CY2021Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	34900000	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
CY2021Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3711905000	USD
CY2021Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	43426000	USD
CY2021Q4	bhlb	Fair Value Estimates Impactof Settledto Market Contract FairValueEstimatesImpactofSettledtoMarketContract	45700000	USD
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3857115000	USD
CY2020Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	94313000	USD
CY2020Q4	bhlb	Fair Value Estimates Impactof Settledto Market Contract FairValueEstimatesImpactofSettledtoMarketContract	97600000	USD
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	52180000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	60018000	USD
CY2021Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	6674000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	7197000	USD
CY2021Q4	bhlb	Lease Rightof Use Asset LeaseRightofUseAsset	58854000	USD
CY2020Q4	bhlb	Lease Rightof Use Asset LeaseRightofUseAsset	67215000	USD
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	10900000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	13500000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	55674000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	63894000	USD
CY2021Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	9862000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10383000	USD
CY2021Q4	bhlb	Lease Liability LeaseLiability	65536000	USD
CY2020Q4	bhlb	Lease Liability LeaseLiability	74277000	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y6M
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y9M18D
CY2021Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P12Y9M18D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P13Y9M18D
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0277
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0281
CY2021Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0500
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0500
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	500000	USD
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	2976000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7083000	USD
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	10897000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	13750000	USD
CY2021	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	503000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	530000	USD
CY2021	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	528000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	9774000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	1031000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	8569000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1037000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	7546000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1037000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	5859000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	1037000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	4639000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	1037000	USD
CY2021	bhlb	Loan Modifications Amount LoanModificationsAmount	14400000	USD
CY2020Q4	bhlb	Financing Receivable Modifications Active Modified Loans FinancingReceivableModificationsActiveModifiedLoans	746	loan
CY2020Q4	bhlb	Financing Receivable Modifications Active Modified Loans Carrying Value FinancingReceivableModificationsActiveModifiedLoansCarryingValue	316100000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	27568000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	8185000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	63955000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	13364000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	8281000	USD
CY2021Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	3502000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	55674000	USD
CY2021Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	9862000	USD
CY2021	bhlb	Financing Receivable Modifications Numberof Contracts Modifiedunder Interagencyguidanceand Cares Act FinancingReceivableModificationsNumberofContractsModifiedunderInteragencyguidanceandCARESAct	19	loan
CY2021Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	2180227000	USD
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1778480000	USD
CY2021Q4	us-gaap	Capital Capital	1359470000	USD
CY2021Q4	us-gaap	Capital To Risk Weighted Assets CapitalToRiskWeightedAssets	0.1732
CY2021Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	628026000	USD
CY2021Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0800
CY2021Q4	us-gaap	Common Equity Tier One Capital CommonEquityTierOneCapital	1178497000	USD
CY2021Q4	us-gaap	Common Equity Tier One Capital Ratio CommonEquityTierOneCapitalRatio	0.1501
CY2021Q4	us-gaap	Common Equity Tier One Capital Required For Capital Adequacy CommonEquityTierOneCapitalRequiredForCapitalAdequacy	353265000	USD
CY2021Q4	us-gaap	Banking Regulation Common Equity Tier One Risk Based Capital Ratio Capital Adequacy Minimum BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum	0.0450
CY2021Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	1200732000	USD
CY2021Q4	us-gaap	Tier One Risk Based Capital To Risk Weighted Assets TierOneRiskBasedCapitalToRiskWeightedAssets	0.1530
CY2021Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	471020000	USD
CY2021Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0600
CY2021Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	1200732000	USD
CY2021Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.1049
CY2021Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	314013000	USD
CY2021Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy To Average Assets TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets	0.0400
CY2021Q4	us-gaap	Risk Weighted Assets RiskWeightedAssets	7850331000	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	us-gaap	Common Equity Tier One Capital CommonEquityTierOneCapital	1145329000	USD
CY2020Q4	us-gaap	Common Equity Tier One Capital Ratio CommonEquityTierOneCapitalRatio	0.1379
CY2020Q4	us-gaap	Common Equity Tier One Capital Required For Capital Adequacy CommonEquityTierOneCapitalRequiredForCapitalAdequacy	373634000	USD
CY2020Q4	us-gaap	Banking Regulation Common Equity Tier One Risk Based Capital Ratio Well Capitalized Minimum BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum	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
CY2019	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	420000	shares
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
CY2020Q4	us-gaap	Risk Weighted Assets RiskWeightedAssets	8302987000	USD
CY2021Q4	us-gaap	Banking Regulation Common Equity Tier One Risk Based Capital Ratio Capital Adequacy Minimum BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum	0.0450
CY2020Q4	us-gaap	Banking Regulation Common Equity Tier One Risk Based Capital Ratio Capital Adequacy Minimum BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum	0.0450
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-45801000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-11687000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-34114000	USD
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
CY2021	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-34114000	USD
CY2021	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	0	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-34114000	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
CY2021	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	118664000	USD
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-513175000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	101521000	USD
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	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
CY2021	us-gaap	Net Income Loss NetIncomeLoss	118664000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2021	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	51903000	shares
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
CY2021	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	1951000	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
CY2021	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	712000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	505000	shares
CY2021	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	0	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
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49240000	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
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49554000	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
CY2021	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.41
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
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0
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
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.41
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-10.60
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.97
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-10.60
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
CY2021	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.39
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
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
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
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.39
CY2021	bhlb	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 Number Of Transfers FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3NumberOfTransfers	1	transfer
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	4000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	0	USD
CY2019	bhlb	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 Number Of Transfers FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3NumberOfTransfers	4	transfer
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	44000000	USD
CY2021Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	75860000	USD
CY2021Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	79688000	USD
CY2021Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	85364000	USD
CY2021Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	88153000	USD
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
CY2021Q4	us-gaap	Interest Expense InterestExpense	6548000	USD
CY2021Q3	us-gaap	Interest Expense InterestExpense	8320000	USD
CY2021Q2	us-gaap	Interest Expense InterestExpense	9971000	USD
CY2021Q1	us-gaap	Interest Expense InterestExpense	13060000	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
CY2021Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	69312000	USD
CY2021Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	71368000	USD
CY2021Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	75393000	USD
CY2021Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	75093000	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
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	86428000	USD
CY2021Q4	us-gaap	Noninterest Income NoninterestIncome	21409000	USD
CY2021Q3	us-gaap	Noninterest Income NoninterestIncome	73635000	USD
CY2021Q2	us-gaap	Noninterest Income NoninterestIncome	22011000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	26193000	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
CY2021Q4	us-gaap	Revenues Revenues	90721000	USD
CY2021Q3	us-gaap	Revenues Revenues	145003000	USD
CY2021Q2	us-gaap	Revenues Revenues	97404000	USD
CY2021Q1	us-gaap	Revenues Revenues	101286000	USD
CY2020Q4	us-gaap	Revenues Revenues	99036000	USD
CY2020Q3	us-gaap	Revenues Revenues	97018000	USD
CY2020Q2	us-gaap	Revenues Revenues	94971000	USD
CY2020Q1	us-gaap	Revenues Revenues	92064000	USD
CY2021Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-3000000	USD
CY2021Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-4000000	USD
CY2021Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
CY2021Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	6500000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-14068000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	17240000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	22975000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-559175000	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
CY2020Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	29871000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	34807000	USD
CY2021Q4	us-gaap	Noninterest Expense NoninterestExpense	69407000	USD
CY2021Q3	us-gaap	Noninterest Expense NoninterestExpense	69460000	USD
CY2021Q2	us-gaap	Noninterest Expense NoninterestExpense	68872000	USD
CY2021Q1	us-gaap	Noninterest Expense NoninterestExpense	78154000	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
CY2021Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	24314000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	79543000	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	28532000	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	16632000	USD
CY2021Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4066000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	15794000	USD
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6896000	USD
CY2021Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3601000	USD
CY2020Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-1818000	USD
CY2020Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-7798000	USD
CY2021Q4	us-gaap	Net Income Loss NetIncomeLoss	20248000	USD
CY2020Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1659000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-68000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-16130000	USD
CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1996000	USD
CY2021Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	20248000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	63749000	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	21636000	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	13031000	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
CY2021Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	0	USD
CY2021Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	0	USD
CY2021Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	0	USD
CY2021Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	0	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
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	63749000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	21636000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	13031000	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
CY2021Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.42
CY2021Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.32
CY2021Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.43
CY2021Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.26
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
CY2020Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	-0.24
CY2021Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0
CY2021Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0
CY2021Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0
CY2021Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0
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
CY2021Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.42
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.32
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.43
CY2021Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.26
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
CY2021Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.42
CY2021Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.31
CY2021Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.43
CY2021Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.26
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
CY2021Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
CY2021Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
CY2021Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
CY2021Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
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
CY2021Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.42
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.31
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.43
CY2021Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.26
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
CY2021Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	47958000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	48395000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50321000	shares
CY2021Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50330000	shares
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
CY2021Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	48340000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	48744000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50608000	shares
CY2021Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50565000	shares
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-5539000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50329000	shares
CY2020Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50355000	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
CY2021	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	291166000	USD
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	316782000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	365258000	USD
CY2021	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-500000	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
CY2021	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	291666000	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
CY2021	us-gaap	Noninterest Income NoninterestIncome	143248000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	66307000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD
CY2021	us-gaap	Noninterest Expense NoninterestExpense	285893000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	840239000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	289857000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	149021000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-533028000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	123984000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	30357000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19853000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	118664000	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
CY2021	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	0	USD
CY2020	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-26855000	USD
CY2021	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	0	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
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	0	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
CY2021	us-gaap	Net Income Loss NetIncomeLoss	118664000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-533017000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	46103000	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
CY2021	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	97145000	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
CY2021	us-gaap	Noninterest Income NoninterestIncome	143248000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	66307000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD

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$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb

2021 Q4 Form 10-K Financial Statement

#000110813422000004 Filed on March 01, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BHLB BERKSHIRE HILLS BANCORP INC Stock $bhlb

2021 Q4 Form 10-K Financial Statement

#000110813422000004 Filed on March 01, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb