$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb

$bhlb Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000110813420000002 Filed on February 28, 2020

Income Statement

Concept	2019 Q4	2019	2018 Q4
Revenue	$114.7M	$449.3M	$108.5M
YoY Change	5.67%	4.35%	-6.16%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$26.52M
YoY Change		-2.3%
% of Gross Profit
Depreciation & Amortization	$4.700M	$16.70M	$4.200M
YoY Change	11.9%	6.37%	13.51%
% of Gross Profit
Operating Expenses		$26.52M
YoY Change		-2.3%
Operating Profit
YoY Change
Interest Expense	$34.11M	$144.3M	$33.93M
YoY Change	0.53%	31.51%	74.38%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$39.06M	$124.0M	$21.45M
YoY Change	82.07%	-10.27%	10.11%
Income Tax	$6.421M	$22.46M	$4.384M
% Of Pretax Income	16.44%	18.12%	20.44%
Net Earnings	$25.75M	$97.45M	$14.26M
YoY Change	80.59%	-7.86%	-607.44%
Net Earnings / Revenue	22.45%	21.69%	13.14%
Basic Earnings Per Share	$0.51	$1.98	$0.31
Diluted Earnings Per Share	$0.51	$1.97	$0.31
COMMON SHARES
Basic Shares Outstanding	50.49M shares	49.26M shares	46.06M shares
Diluted Shares Outstanding	50.70M shares	49.42M shares	46.24M shares

Balance Sheet

Concept	2019 Q4	2019	2018 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$621.4M		$239.8M
YoY Change	159.1%		-18.41%
Cash & Equivalents	$579.8M		$183.2M
Short-Term Investments	$41.56M		$56.64M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$120.4M	$197.0M	$108.4M
YoY Change	11.1%	82.41%	-0.9%
Goodwill	$553.8M		$518.3M
YoY Change	6.84%		-0.19%
Intangibles	$45.62M		$33.42M
YoY Change	36.5%		-12.74%
Long-Term Investments
YoY Change
Other Assets	$205.0M	$205.0M	$39.00M
YoY Change	425.64%	425.64%	-17.02%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$13.22B	$13.22B	$12.21B
YoY Change	8.22%	8.22%	5.54%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$81.00M	$81.00M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$125.0M		$1.119B
YoY Change	-88.83%		67.67%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$81.00M	$81.00M
YoY Change
LONG-TERM LIABILITIES
Long-Term Debt	$108.0M	$108.0M	$90.00M
YoY Change	20.0%	6.93%	1.12%
Other Long-Term Liabilities	$202.0M	$202.0M	$159.0M
YoY Change	27.04%	36.49%	-15.43%
Total Long-Term Liabilities	$310.0M	$310.0M	$249.0M
YoY Change	24.5%	24.5%	-10.11%
TOTAL LIABILITIES
Total Short-Term Liabilities	$81.00M	$81.00M
Total Long-Term Liabilities	$310.0M	$310.0M	$249.0M
Total Liabilities	$11.46B	$11.46B	$10.66B
YoY Change	7.49%	7.49%	5.81%
SHAREHOLDERS EQUITY
Retained Earnings	$361.1M		$308.8M
YoY Change	16.92%		29.12%
Common Stock	$1.423B		$1.245B
YoY Change	14.25%		0.2%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$69.64M		$21.96M
YoY Change	217.07%		-8.96%
Treasury Stock Shares	2.318M shares		795.0K shares
Shareholders Equity	$1.759B	$1.759B	$1.553B
YoY Change
Total Liabilities & Shareholders Equity	$13.22B	$13.22B	$12.21B
YoY Change	8.22%	8.22%	5.54%

Cashflow Statement

Concept	2019 Q4	2019	2018 Q4
OPERATING ACTIVITIES
Net Income	$25.75M	$97.45M	$14.26M
YoY Change	80.59%	-7.86%	-607.44%
Depreciation, Depletion And Amortization	$4.700M	$16.70M	$4.200M
YoY Change	11.9%	6.37%	13.51%
Cash From Operating Activities	$107.8M	$111.5M	$40.60M
YoY Change	165.52%	-49.82%	48.72%
INVESTING ACTIVITIES
Capital Expenditures	-$2.100M	$10.57M	-$100.0K
YoY Change	2000.0%	13.01%	-96.43%
Acquisitions
YoY Change
Other Investing Activities	$467.5M	$4.387M	-$177.0M
YoY Change	-364.12%	-7.13%	-166.87%
Cash From Investing Activities	$465.5M	$1.203B	-$177.0M
YoY Change	-362.99%	-239.59%	-167.58%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$52.75M
YoY Change
Debt Paid & Issued, Net		$6.229B
YoY Change		41.98%
Cash From Financing Activities	-295.6M	-$917.5M	183.9M
YoY Change	-260.74%	-259.92%	-238.79%
NET CHANGE
Cash From Operating Activities	107.8M	$111.5M	40.60M
Cash From Investing Activities	465.5M	$1.203B	-177.0M
Cash From Financing Activities	-295.6M	-$917.5M	183.9M
Net Change In Cash	277.7M	$396.6M	47.50M
YoY Change	484.63%	-704.87%	-69.69%
FREE CASH FLOW
Cash From Operating Activities	$107.8M	$111.5M	$40.60M
Capital Expenditures	-$2.100M	$10.57M	-$100.0K
Free Cash Flow	$109.9M	$101.0M	$40.70M
YoY Change	170.02%	-52.58%	35.22%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0001108134
CY2019	dei	Entity Registrant Name EntityRegistrantName	BERKSHIRE HILLS BANCORP INC
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CY2019	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	26523000	USD
CY2018	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	27147000	USD
CY2017	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	24450000	USD
CY2019	us-gaap	Marketing Expense MarketingExpense	4474000	USD
CY2018	us-gaap	Marketing Expense MarketingExpense	4697000	USD
CY2017	us-gaap	Marketing Expense MarketingExpense	6528000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	10798000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	7343000	USD
CY2017	us-gaap	Professional Fees ProfessionalFees	7507000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3861000	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	5734000	USD
CY2017	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	6457000	USD
CY2019	bhlb	Other Real Estate Owned OtherRealEstateOwned	154000	USD
CY2018	bhlb	Other Real Estate Owned OtherRealEstateOwned	68000	USD
CY2017	bhlb	Other Real Estate Owned OtherRealEstateOwned	44000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5783000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4934000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3493000	USD
CY2019	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	28046000	USD
CY2018	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	22144000	USD
CY2017	us-gaap	Other Nonrecurring Expense OtherNonrecurringExpense	31558000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	29726000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	23880000	USD
CY2017	us-gaap	Other Noninterest Expense OtherNoninterestExpense	21196000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	289857000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	266893000	USD
CY2017	us-gaap	Noninterest Expense NoninterestExpense	252978000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	123984000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	138180000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	91204000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	28961000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	42088000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	109219000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	49116000	USD
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	-5539000	USD
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	-4767000	USD
CY2017	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	8545000	USD
CY2019	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1468000	USD
CY2018	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1313000	USD
CY2017	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	2414000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-3454000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	6131000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	55247000	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	960000	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	918000	USD
CY2017	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	219000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	96490000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	104847000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	34260000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	55028000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.06
CY2018	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.38
CY2017	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.24
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.08
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.08
CY2017	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.16
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.30
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.40
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.05
CY2018	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.36
CY2017	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.24
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.08
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.07
CY2017	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.15
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.97
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.29
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.39
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49263000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46024000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	39456000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49421000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46231000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	39695000	shares
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	55247000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	34530000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-16923000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-15142000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	6573000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	270000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-336000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	94000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-16587000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-8663000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	8873000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-4421000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-5610000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	0	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	2589000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	76000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-108000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	37000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	8797000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-4313000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-3058000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-5605000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	122913000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	93491000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	49642000	USD
CY2016Q4	us-gaap	Stockholders Equity StockholdersEquity	1093298000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	55247000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-5605000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	49642000	USD
CY2017	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	152984000	USD
CY2017	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	33022000	USD
CY2017	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	219000	USD
CY2017	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	USD
CY2017	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	329000	USD
CY2017	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	5102000	USD
CY2017	us-gaap	Stockholders Equity Other StockholdersEquityOther	1083000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	1496264000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	93491000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	39966000	USD
CY2018	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	918000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	326000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4759000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	1038000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1552918000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	122913000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	44147000	USD
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
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	109219000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	49116000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-3454000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	6131000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	55247000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	35419000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25451000	USD
CY2017	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	21025000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2407000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2837000	USD
CY2017	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1678000	USD
CY2019	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-12759000	USD
CY2018	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	1004000	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
CY2017	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-686000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-5000	USD
CY2017	bhlb	Change In Unamortized Net Loan Costs And Premiums ChangeInUnamortizedNetLoanCostsAndPremiums	-2232000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	10921000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	10442000	USD
CY2017	us-gaap	Depreciation And Amortization DepreciationAndAmortization	9499000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	4812000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	4759000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	5102000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	-14813000	USD
CY2018	us-gaap	Adjustment For Amortization AdjustmentForAmortization	-24000000	USD
CY2017	us-gaap	Adjustment For Amortization AdjustmentForAmortization	-18189000	USD
CY2019	bhlb	Amortization Of Other Intangible Assets AmortizationOfOtherIntangibleAssets	5783000	USD
CY2018	bhlb	Amortization Of Other Intangible Assets AmortizationOfOtherIntangibleAssets	4934000	USD
CY2017	bhlb	Amortization Of Other Intangible Assets AmortizationOfOtherIntangibleAssets	3493000	USD
CY2019	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	0	USD
CY2018	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	0	USD
CY2017	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	10000	USD
CY2019	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	5349000	USD
CY2018	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	6232000	USD
CY2017	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	3615000	USD
CY2019	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	4389000	USD
CY2018	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-3719000	USD
CY2017	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	12598000	USD
CY2019	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	5137000	USD
CY2018	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	-1460000	USD
CY2017	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	-10511000	USD
CY2019	bhlb	Increase Decrease In Lease Right Of Use Assets IncreaseDecreaseInLeaseRightOfUseAssets	-12031000	USD
CY2019	bhlb	Increase Decrease In Lease Liabilities IncreaseDecreaseInLeaseLiabilities	-12217000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-3443000	USD
CY2018	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-152000	USD
CY2017	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	51000	USD
CY2019	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	6455000	USD
CY2018	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	4618000	USD
CY2017	bhlb	Amortization Of Tax Credits AmortizationOfTaxCredits	8477000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	0	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	0	USD
CY2017	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-18145000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	23232000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-30601000	USD
CY2017	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-13842000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	130419000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	166956000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	109363000	USD
CY2019	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	-18894000	USD
CY2018	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	55298000	USD
CY2017	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	-31272000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	111525000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	222254000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	78091000	USD
CY2019	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-701000	USD
CY2018	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-665000	USD
CY2017	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-632000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	23841000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	24538000	USD
CY2017	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	27435000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	43075000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	38104000	USD
CY2017	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	51382000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	119671000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	257547000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	471211000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	136229000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	499000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	137539000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	240586000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	188076000	USD
CY2017	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	206648000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	7260000	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	15391000	USD
CY2017	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	77208000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	21602000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	36746000	USD
CY2017	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	12600000	USD
CY2019	bhlb	Proceeds From Loans And Leases Held For Investment Excluding Seasoned Commercial Loans ProceedsFromLoansAndLeasesHeldForInvestmentExcludingSeasonedCommercialLoans	694657000	USD
CY2018	bhlb	Payments To Acquire Loans And Leases Held For Investment Excluding Seasoned Commercial Loans PaymentsToAcquireLoansAndLeasesHeldForInvestmentExcludingSeasonedCommercialLoans	801876000	USD
CY2017	bhlb	Payments To Acquire Loans And Leases Held For Investment Excluding Seasoned Commercial Loans PaymentsToAcquireLoansAndLeasesHeldForInvestmentExcludingSeasonedCommercialLoans	468331000	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	110774000	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	USD
CY2017	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	374611000	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2451000	USD
CY2018	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	854000	USD
CY2017	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	310000	USD
CY2019	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2018	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2017	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	20000000	USD
CY2019	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	112208000	USD
CY2018	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	76090000	USD
CY2017	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	88351000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	149455000	USD
CY2018	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	61831000	USD
CY2017	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	96378000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4387000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4724000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	5102000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	10565000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9349000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11256000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	81147000	USD
CY2018	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	0	USD
CY2017	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	0	USD
CY2019	us-gaap	Proceeds From Hedge Investing Activities ProceedsFromHedgeInvestingActivities	0	USD
CY2018	us-gaap	Proceeds From Hedge Investing Activities ProceedsFromHedgeInvestingActivities	0	USD
CY2017	us-gaap	Proceeds From Hedge Investing Activities ProceedsFromHedgeInvestingActivities	6573000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	150000	USD
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	1600000	USD
CY2017	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	590000	USD
CY2019	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-313000	USD
CY2018	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-377000	USD
CY2017	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-1272000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1202582000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-861517000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-282903000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	23996000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	233704000	USD
CY2017	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	418550000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	5384982000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	4767766000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	5978358000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	6228780000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	4387223000	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	6174781000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	152985000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	52746000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	188000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	326000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	329000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	45107000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	40884000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	33241000	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	0	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	0	USD
CY2017	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1700000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-917467000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	573689000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	340500000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	396640000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-65574000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	135688000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	183189000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	248763000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	113075000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	579829000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	183189000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	248763000	USD
CY2019	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	119695000	USD
CY2018	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	74565000	USD
CY2017	bhlb	Interest Paid On Deposits InterestPaidOnDeposits	43133000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	33406000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	32274000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	21336000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	19818000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	3029000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	18323000	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	1595054000	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	0	USD
CY2017	us-gaap	Noncash Or Part Noncash Acquisition Value Of Assets Acquired1 NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1	1584786000	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	1530010000	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	0	USD
CY2017	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	1959489000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-5605000	USD
CY2019	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	0	USD
CY2018	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	1600000	USD
CY2017	bhlb	Real Estate Owned Acquired In Settlement Of Loans RealEstateOwnedAcquiredInSettlementOfLoans	490000	USD
CY2019	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	120307000	USD
CY2018	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	0	USD
CY2017	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	0	USD
CY2019	bhlb	Noncash Or Part Noncash Acquisition Goodwill Acquired Measurement Period Adjustments NoncashOrPartNoncashAcquisitionGoodwillAcquiredMeasurementPeriodAdjustments	942000	USD
CY2018	bhlb	Noncash Or Part Noncash Acquisition Goodwill Acquired Measurement Period Adjustments NoncashOrPartNoncashAcquisitionGoodwillAcquiredMeasurementPeriodAdjustments	0	USD
CY2017	bhlb	Noncash Or Part Noncash Acquisition Goodwill Acquired Measurement Period Adjustments NoncashOrPartNoncashAcquisitionGoodwillAcquiredMeasurementPeriodAdjustments	0	USD
CY2019	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="line-height:120%;text-align:left;font-size:11pt;"><span style="font-family:inherit;font-size:11pt;font-style:italic;font-weight:bold;">Reclassifications</span></div><div style="line-height:120%;padding-top:3px;text-align:left;font-size:11pt;"><span style="font-family:inherit;font-size:11pt;">Certain items in prior financial statements have been reclassified to conform to the current presentation.</span></div><div style="line-height:120%;text-align:left;font-size:11pt;"><span style="font-family:inherit;font-size:11pt;"><br/></span></div>
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;text-align:left;font-size:11pt;"><span style="font-family:inherit;font-size:11pt;font-style:italic;font-weight:bold;">Use of Estimates</span></div><div style="line-height:120%;text-align:left;font-size:11pt;"><span style="font-family:inherit;font-size:11pt;">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 style="line-height:120%;text-align:left;font-size:11pt;"><span style="font-family:inherit;font-size:11pt;"><br/></span></div>
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1311555000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1297339000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	16503000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	2287000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	357979000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	16263000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	965000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	373277000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	37138000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	5147000	USD
CY2019	bhlb	Defined Benefit Plan Net Actuarial Gain Loss Threshold Percentage For Amortization In Net Periodic Benefit Cost Minimum DefinedBenefitPlanNetActuarialGainLossThresholdPercentageForAmortizationInNetPeriodicBenefitCostMinimum	0.10
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	segment
CY2019	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	729000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	18300000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	18000000.0	USD
CY2019Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	9400000	USD
CY2018Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	10100000	USD
CY2019Q4	us-gaap	Trading Securities TradingSecurities	10800000	USD
CY2018Q4	us-gaap	Trading Securities TradingSecurities	11200000	USD
CY2019	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	300000	USD
CY2018	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	400000	USD
CY2017	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	300000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	41556000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAmortizedCost	1692456000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Gainbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedGainbeforeTax	37913000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Lossbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedLossbeforeTax	3981000	USD
CY2019Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNI	1726388000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1421273000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	4065000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	25691000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1399647000	USD
CY2018Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	373763000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	4124000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	6663000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	371224000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	55471000	USD
CY2018	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	4370000	USD
CY2018	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	3203000	USD
CY2018Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	56638000	USD
CY2018Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAmortizedCost	1850507000	USD
CY2018Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Gainbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedGainbeforeTax	12559000	USD
CY2018Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni Accumulated Gross Unrealized Lossbefore Tax DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNIAccumulatedGrossUnrealizedLossbeforeTax	35557000	USD
CY2018Q4	bhlb	Debt Securities Availableforsaleand Heldtomaturityand Equity Securities Fvni DebtSecuritiesAvailableforsaleandHeldtomaturityandEquitySecuritiesFVNI	1827509000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis	34900000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Fair Value AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	34996000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	1849000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Next Rolling Twelve Months Fair Value HeldToMaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	1849000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis	20372000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	20292000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	14269000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling Year Two Through Five Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	14403000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis	68139000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	69673000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	12541000	USD
CY2018Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Amortized Cost SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsAmortizedCost	187636000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling Year Six Through Ten Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	12711000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis	136723000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue	142942000	USD
CY2019Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	243029000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingAfterTenYearsFairValue	255123000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	260134000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	267903000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	271688000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	284086000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	1037205000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	1043652000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	86291000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	89191000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1297339000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1311555000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	357979000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	373277000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Amortized Cost SecurityOwnedAndPledgedAsCollateralForInterestRateSwapAmortizedCost	25728000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Fair Value SecurityOwnedAndPledgedAsCollateralForInterestRateSwapFairValue	25828000	USD
CY2018Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Amortized Cost SecurityOwnedAndPledgedAsCollateralForInterestRateSwapAmortizedCost	13093000	USD
CY2018Q4	bhlb	Security Owned And Pledged As Collateral For Interest Rate Swap Fair Value SecurityOwnedAndPledgedAsCollateralForInterestRateSwapFairValue	12819000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Amortized Cost SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsAmortizedCost	168740000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Fair Value SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsFairValue	175719000	USD
CY2018Q4	bhlb	Security Owned And Pledged As Collateral For Municipal Deposits Fair Value SecurityOwnedAndPledgedAsCollateralForMunicipalDepositsFairValue	188423000	USD
CY2019Q4	bhlb	Security Owned And Pledged As Collateral Amortized Cost SecurityOwnedAndPledgedAsCollateralAmortizedCost	194468000	USD
CY2019Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	201547000	USD
CY2018Q4	bhlb	Security Owned And Pledged As Collateral Amortized Cost SecurityOwnedAndPledgedAsCollateralAmortizedCost	200729000	USD
CY2018Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	201242000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	120000000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	258000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	136000000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	500000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	7492000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	3256000	USD
CY2017	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	13877000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedLossExcludingOtherThanTemporaryImpairment	3103000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedLossExcludingOtherThanTemporaryImpairment	6975000	USD
CY2017	us-gaap	Debt Securities Available For Sale Realized Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedLossExcludingOtherThanTemporaryImpairment	1279000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	4389000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	-3719000	USD
CY2017	us-gaap	Debt Securities Available For Sale Realized Gain Loss Excluding Other Than Temporary Impairment DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment	12598000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1287000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	180826000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	83773000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	2287000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	264599000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	55000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	10578000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	910000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	6925000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	965000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	17503000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLosses	1342000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan Twelve Months Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue	191404000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLosses	1910000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Twelve Monthsor Longer Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue	90698000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses	3252000	USD
CY2019Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionFairValue	282102000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1576000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	130805000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	24115000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	992767000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	25691000	USD
CY2018Q4	bhlb	Unamortized Discounts Or Premiums UnamortizedDiscountsOrPremiums	2792000	USD
CY2019Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	15902000	USD
CY2018Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	1123572000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	192000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	25674000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	6471000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	170459000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	6663000	USD
CY2018Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	196133000	USD
CY2018Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan12 Months Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAggregateLosses	1768000	USD
CY2018Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Lessthan Twelve Months Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue	156479000	USD
CY2018Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position12 Monthsor Longer Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLosses	30586000	USD
CY2018Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Twelve Monthsor Longer Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue	1163226000	USD
CY2018Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Aggregate Losses DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionAggregateLosses	32354000	USD
CY2018Q4	bhlb	Debt Securities Heldto Maturityand Availablefor Sale Securities Continuous Unrealized Loss Position Fair Value DebtSecuritiesHeldtoMaturityandAvailableforSaleSecuritiesContinuousUnrealizedLossPositionFairValue	1319705000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	9502428000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	9043253000	USD
CY2019Q4	bhlb	Unamortized Loan Origination Fees UnamortizedLoanOriginationFees	13259000	USD
CY2018Q4	bhlb	Unamortized Loan Origination Fees UnamortizedLoanOriginationFees	25761000	USD
CY2019Q4	bhlb	Unamortized Discounts Or Premiums UnamortizedDiscountsOrPremiums	2643000	USD
CY2018Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	28553000	USD
CY2019	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	432000000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans And Leases Held For Investment ProceedsFromSaleOfLoansAndLeasesHeldForInvestment	310000000	USD
CY2018	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	567000000	USD
CY2018	us-gaap	Proceeds From Sale Of Loans And Leases Held For Investment ProceedsFromSaleOfLoansAndLeasesHeldForInvestment	388000000	USD
CY2019	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	12000000.0	USD
CY2018	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	9300000	USD
CY2017	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	11700000	USD
CY2019Q4	us-gaap	Loans Pledged As Collateral LoansPledgedAsCollateral	285000000	USD
CY2019Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	1800000	USD
CY2018Q4	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	52900000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	1000000.0	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	47800000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	2840000	USD
CY2017Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	11561000	USD
CY2016Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	8738000	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	9619000	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	23109000	USD
CY2017	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	14810000	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	4200000	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	0	USD
CY2017	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	10815000	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	7430000	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	17347000	USD
CY2017	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications To From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsToFromNonaccretableDifference	9198000	USD
CY2019	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Payments Received CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldPaymentsReceived	837000	USD
CY2018	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Payments Received CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldPaymentsReceived	2878000	USD
CY2017	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Payments Received CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldPaymentsReceived	2380000	USD
CY2019	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Reclassificationsto Troubled Debt Restructuring CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldReclassificationstoTroubledDebtRestructuring	-9000	USD
CY2018	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Reclassificationsto Troubled Debt Restructuring CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldReclassificationstoTroubledDebtRestructuring	0	USD
CY2017	bhlb	Certain Loans Acquiredin Transfer Not Accountedforas Debt Securities Accretable Yield Reclassificationsto Troubled Debt Restructuring CertainLoansAcquiredinTransferNotAccountedforasDebtSecuritiesAccretableYieldReclassificationstoTroubledDebtRestructuring	0	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	0	USD
CY2018	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	81000	USD
CY2017	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Disposals Of Loans CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldDisposalsOfLoans	0	USD
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	4023000	USD
CY2018Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	2840000	USD
CY2017Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	11561000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	39640000	USD
CY2018Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	32425000	USD
CY2019Q4	bhlb	Impaired Financing Receivable Additional Funds Committed Amount ImpairedFinancingReceivableAdditionalFundsCommittedAmount	0	USD
CY2019	bhlb	Troubled Debt Restructuring Sustained Repayment Period Of Borrower To Consider Return To Performing Status TroubledDebtRestructuringSustainedRepaymentPeriodOfBorrowerToConsiderReturnToPerformingStatus	P6M
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	13	modification
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	2063000	USD
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	2063000	USD
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	10	modification
CY2018	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	2685000	USD
CY2018	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	2685000	USD
CY2017	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	35	modification
CY2017	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	17640000	USD
CY2017	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	15896000	USD
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	contract
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	contract
CY2017	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	3	contract
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	contract
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	195000	USD
CY2017	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	3	contract
CY2017	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	605000	USD
CY2018Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	27415000	USD
CY2017Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	41990000	USD
CY2016Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	33829000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	6086000	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	8547000	USD
CY2017	bhlb	Financing Receivable Troubled Debt Restructuring Principal Payments FinancingReceivableTroubledDebtRestructuringPrincipalPayments	3213000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2017	bhlb	Financing Receivable Troubled Debt Restructuring Status Change FinancingReceivableTroubledDebtRestructuringStatusChange	0	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Other Reductions FinancingReceivableTroubledDebtRestructuringOtherReductions	4076000	USD
CY2018	us-gaap	Servicing Asset At Amortized Value Other Changes That Affect Balance Amount ServicingAssetAtAmortizedValueOtherChangesThatAffectBalanceAmount	-29000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	-4700000	USD
CY2018Q4	bhlb	Reciprocal Money Market Deposits ReciprocalMoneyMarketDeposits	84400000	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Other Reductions FinancingReceivableTroubledDebtRestructuringOtherReductions	8713000	USD
CY2017	bhlb	Financing Receivable Troubled Debt Restructuring Other Reductions FinancingReceivableTroubledDebtRestructuringOtherReductions	4522000	USD
CY2019	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	2063000	USD
CY2018	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	2685000	USD
CY2017	bhlb	Financing Receivable Troubled Debt Restructuring Additions FinancingReceivableTroubledDebtRestructuringAdditions	15896000	USD
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	19316000	USD
CY2018Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	27415000	USD
CY2017Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	41990000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	200437000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	176807000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	78966000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	68440000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	121471000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	108367000	USD
CY2019	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	11800000	USD
CY2018	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	10800000	USD
CY2017	bhlb	Depreciation Depletion And Amortization Nonproduction Including Discontinued Operations DepreciationDepletionAndAmortizationNonproductionIncludingDiscontinuedOperations	9900000	USD
CY2019	bhlb	Business Acquisition Number Of Significant Acquisitions Completed BusinessAcquisitionNumberOfSignificantAcquisitionsCompleted	1	acquisition
CY2018	bhlb	Business Acquisition Number Of Significant Acquisitions Completed BusinessAcquisitionNumberOfSignificantAcquisitionsCompleted	0	acquisition
CY2018Q4	us-gaap	Goodwill Goodwill	518325000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	519287000	USD
CY2019	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	942000	USD
CY2018	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	962000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	553762000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	518325000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	100327000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	54712000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	45615000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	82347000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	48929000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	33418000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5800000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4900000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3500000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	6200000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	6000000.0	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	5900000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	5600000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	5400000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	16600000	USD
CY2019	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	0	USD
CY2018	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	-550000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	26451000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	23376000	USD
CY2019Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	12300000	USD
CY2018Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	11500000	USD
CY2018Q4	us-gaap	Time Deposits TimeDeposits	3287717000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	26451000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	23376000	USD
CY2019Q4	us-gaap	Interest Receivable InterestReceivable	36462000	USD
CY2018Q4	us-gaap	Interest Receivable InterestReceivable	36879000	USD
CY2019Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	23786000	USD
CY2018Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	23923000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	76332000	USD
CY2018Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	0	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	80190000	USD
CY2018Q4	us-gaap	Derivative Assets DerivativeAssets	35654000	USD
CY2019Q4	bhlb	Other Assets Held For Sale OtherAssetsHeldForSale	1734000	USD
CY2018Q4	bhlb	Other Assets Held For Sale OtherAssetsHeldForSale	1541000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	16647000	USD
CY2018Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	21165000	USD
CY2019Q4	us-gaap	Other Assets OtherAssets	261602000	USD
CY2018Q4	us-gaap	Other Assets OtherAssets	142538000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	23376000	USD
CY2017Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	16361000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	16837000	USD
CY2018	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	10660000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3240000	USD
CY2018	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3124000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Other Changes That Affect Balance Amount ServicingAssetAtAmortizedValueOtherChangesThatAffectBalanceAmount	5822000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	2734870000	USD
CY2018Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	2142943000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	582622000	USD
CY2018Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	717706000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	145976000	USD
CY2018Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	217840000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	90731000	USD
CY2018Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	109891000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	33754000	USD
CY2018Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	96479000	USD
CY2019Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	1416000	USD
CY2018Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	2858000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	3589369000	USD
CY2019Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	905190000	USD
CY2018Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	719689000	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	2027717000	USD
CY2018Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	2060500000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	656462000	USD
CY2018Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	507528000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	3589369000	USD
CY2018Q4	us-gaap	Time Deposits TimeDeposits	3287717000	USD
CY2019Q4	bhlb	Brokered Time Deposits BrokeredTimeDeposits	1200000000	USD
CY2018Q4	bhlb	Brokered Time Deposits BrokeredTimeDeposits	1400000000	USD
CY2019Q4	bhlb	Reciprocal Money Market Deposits ReciprocalMoneyMarketDeposits	91700000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	125000000	USD
CY2019Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0206
CY2018Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	1118832000	USD
CY2018Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0258
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	702550000	USD
CY2019Q4	us-gaap	Longterm Debt Weighted Average Interest Rate LongtermDebtWeightedAverageInterestRate	0.0272
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	398984000	USD
CY2018Q4	us-gaap	Longterm Debt Weighted Average Interest Rate LongtermDebtWeightedAverageInterestRate	0.0316
CY2019Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	827550000	USD
CY2019Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0262
CY2018Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	1517816000	USD
CY2018Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0273
CY2019Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	730501000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	0	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	80681000	USD
CY2018Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	33973000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10883000	USD
CY2018Q4	us-gaap	Capital Lease Obligations CapitalLeaseObligations	10986000	USD
CY2019Q4	us-gaap	Other Payables To Broker Dealers And Clearing Organizations OtherPayablesToBrokerDealersAndClearingOrganizations	189000	USD
CY2018Q4	us-gaap	Other Payables To Broker Dealers And Clearing Organizations OtherPayablesToBrokerDealersAndClearingOrganizations	5727000	USD
CY2019Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	44781000	USD
CY2018Q4	us-gaap	Pension And Other Postretirement And Postemployment Benefit Plans Liabilities Current And Noncurrent PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesCurrentAndNoncurrent	27229000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80734000	USD
CY2018Q4	bhlb	Level Lease Liability LevelLeaseLiability	5674000	USD
CY2019Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	11625000	USD
CY2018Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	11808000	USD
CY2019Q4	bhlb	Customer Transaction Clearing Accounts Payable CustomerTransactionClearingAccountsPayable	4310000	USD
CY2018Q4	bhlb	Customer Transaction Clearing Accounts Payable CustomerTransactionClearingAccountsPayable	17574000	USD
CY2019Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	60676000	USD
CY2018Q4	us-gaap	Other Sundry Liabilities OtherSundryLiabilities	46145000	USD
CY2019Q4	us-gaap	Other Liabilities OtherLiabilities	293879000	USD
CY2018Q4	us-gaap	Other Liabilities OtherLiabilities	159116000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-344000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4100000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3900000	USD
CY2017	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	3400000	USD
CY2019Q4	bhlb	Postemployment Benefits Liability Split Dollar Agreement PostemploymentBenefitsLiabilitySplitDollarAgreement	7100000	USD
CY2018Q4	bhlb	Postemployment Benefits Liability Split Dollar Agreement PostemploymentBenefitsLiabilitySplitDollarAgreement	4600000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	16576000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	12634000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	10092000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	5323000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	4114000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	292000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	21899000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16748000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	10384000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	908000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	8443000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	29824000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3770000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1805000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	564000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	12213000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	31629000	USD
CY2019	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	0	USD
CY2018	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	0	USD
CY2017	bhlb	Income Tax Expense Benefit Valuation Allowance Change In Amount IncomeTaxExpenseBenefitValuationAllowanceChangeInAmount	-75000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	28961000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	42088000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	31600000	USD
CY2017	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Change In Tax Rate Deferred Tax Asset Provisional Income Tax Expense TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateDeferredTaxAssetProvisionalIncomeTaxExpense	18100000	USD
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
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	29018000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	31921000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
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
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	7081000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.051
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1699000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.019
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
CY2018	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	3620000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.026
CY2017	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	5395000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.059
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
CY2018	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurance	1337000	USD
CY2018	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance Percent EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurancePercent	0.010
CY2017	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurance	1556000	USD
CY2017	bhlb	Effective Income Tax Rate Reconciliation Bank Owned Life Insurance Percent EffectiveIncomeTaxRateReconciliationBankOwnedLifeInsurancePercent	0.017
CY2019	bhlb	Income Tax Reconciliation Disallowed Merger Costs IncomeTaxReconciliationDisallowedMergerCosts	122000	USD
CY2019	bhlb	Effective Income Tax Rate Reconciliation Disallowed Merger Costs EffectiveIncomeTaxRateReconciliationDisallowedMergerCosts	0.001
CY2018	bhlb	Income Tax Reconciliation Disallowed Merger Costs IncomeTaxReconciliationDisallowedMergerCosts	181000	USD
CY2018	bhlb	Effective Income Tax Rate Reconciliation Disallowed Merger Costs EffectiveIncomeTaxRateReconciliationDisallowedMergerCosts	0.001
CY2018Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	1680000	USD
CY2017	bhlb	Income Tax Reconciliation Disallowed Merger Costs IncomeTaxReconciliationDisallowedMergerCosts	368000	USD
CY2017	bhlb	Effective Income Tax Rate Reconciliation Disallowed Merger Costs EffectiveIncomeTaxRateReconciliationDisallowedMergerCosts	0.004
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	3531000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.028
CY2018	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	3574000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.026
CY2017	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	4656000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.051
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
CY2018	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2017	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	75000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.001
CY2019	bhlb	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Amount EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActAmount	0	USD
CY2019	bhlb	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActPercent	0
CY2018	bhlb	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Amount EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActAmount	0	USD
CY2018	bhlb	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActPercent	0
CY2017	bhlb	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Amount EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActAmount	18721000	USD
CY2017	bhlb	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActPercent	0.205
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
CY2018	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	1212000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.009
CY2017	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	911000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.010
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.181
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	28961000	USD
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.209
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	42088000	USD
CY2017	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.462
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	17446000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	16754000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	6195000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	6045000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	0	USD
CY2018Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	4554000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	10565000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	5161000	USD
CY2018Q4	bhlb	State Tax Basis Difference Net Of Federal Tax Benefit StateTaxBasisDifferenceNetOfFederalTaxBenefit	200000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2018Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0600
CY2019Q4	bhlb	Deferred Tax Assets Purchase Accounting Adjustments DeferredTaxAssetsPurchaseAccountingAdjustments	39359000	USD
CY2018Q4	bhlb	Deferred Tax Assets Purchase Accounting Adjustments DeferredTaxAssetsPurchaseAccountingAdjustments	27249000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	951000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1162000	USD
CY2019Q4	bhlb	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	22497000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	739000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1088000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	2457000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	98840000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	63382000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	98640000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	63182000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	4244000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	0	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1654000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	4669000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	3944000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Financing Costs DeferredTaxLiabilitiesDeferredExpenseDeferredFinancingCosts	1667000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Financing Costs DeferredTaxLiabilitiesDeferredExpenseDeferredFinancingCosts	3310000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	18557000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	13940000	USD
CY2019Q4	bhlb	Deferred Tax Liabilities Unamortized Tax Credit Reserve DeferredTaxLiabilitiesUnamortizedTaxCreditReserve	1142000	USD
CY2018Q4	bhlb	Deferred Tax Liabilities Unamortized Tax Credit Reserve DeferredTaxLiabilitiesUnamortizedTaxCreditReserve	1170000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	20614000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	50893000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	24018000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	47747000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	39164000	USD
CY2019	bhlb	Deferred Tax Assets Liabilities Net Increase Decrease DeferredTaxAssetsLiabilitiesNetIncreaseDecrease	-8600000	USD
CY2019	bhlb	Deferred Income Tax Expense Benefit Purchase Accounting Adjustments DeferredIncomeTaxExpenseBenefitPurchaseAccountingAdjustments	17900000	USD
CY2019Q4	bhlb	State Tax Basis Difference Net Of Federal Tax Benefit StateTaxBasisDifferenceNetOfFederalTaxBenefit	200000	USD
CY2019Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	4070729000	USD
CY2019Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	-492000	USD
CY2018Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3303570000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	200000	USD
CY2019	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	1000000.0	USD
CY2019Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	10883000	USD
CY2019Q3	bhlb	Lease Liability LeaseLiability	91617000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	14400000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	467000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	304000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	460000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	26000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	533000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	370000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	156000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	185000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	70000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	238000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	467000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	304000	USD
CY2019Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	4100000000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	96300000	USD
CY2019Q4	bhlb	Derivative Securities Pledged As Collateral Amortized Cost DerivativeSecuritiesPledgedAsCollateralAmortizedCost	25700000	USD
CY2019Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	25800000	USD
CY2018Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	25400000	USD
CY2018Q4	bhlb	Derivative Securities Pledged As Collateral Amortized Cost DerivativeSecuritiesPledgedAsCollateralAmortizedCost	13100000	USD
CY2018Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	12800000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80734000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	10883000	USD
CY2019Q4	bhlb	Lease Rightof Use Asset LeaseRightofUseAsset	84052000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	80734000	USD
CY2018Q4	bhlb	Common Equity Tier One Risk Based Capital Requiredtobe Well Capitalizedto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitalRequiredtobeWellCapitalizedtoRiskWeightedAssetsAmount	405903000	USD
CY2018Q4	bhlb	Common Equity Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets	0.0450
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0336
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0500
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y3M18D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P14Y9M18D
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	76332000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	7720000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	95701000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	15427000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	14967000	USD
CY2019Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	4544000	USD
CY2018Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	1043898000	USD
CY2018Q4	us-gaap	Tier One Risk Based Capital To Risk Weighted Assets TierOneRiskBasedCapitalToRiskWeightedAssets	0.1157
CY2018Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	541203000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	14731000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	553000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	435000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	88079000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	13763000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	1031000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	12515000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1031000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	11295000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1031000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	9331000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	1037000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	7873000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	1037000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	40924000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	10260000	USD
CY2019Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1835422000	USD
CY2018Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1808643000	USD
CY2019Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	2000000.0	USD
CY2018Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	3000000.0	USD
CY2019Q4	us-gaap	Capital Capital	1321910000	USD
CY2019Q4	us-gaap	Capital To Risk Weighted Assets CapitalToRiskWeightedAssets	0.1373
CY2019Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	770294000	USD
CY2019Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0800
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capitalto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitaltoRiskWeightedAssetsAmount	1161800000	USD
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capital To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets	0.1207
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capital Requiredtobe Well Capitalizedto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitalRequiredtobeWellCapitalizedtoRiskWeightedAssetsAmount	433290000	USD
CY2019Q4	bhlb	Common Equity Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets	0.0450
CY2019Q4	us-gaap	Tier One Risk Based Capital TierOneRiskBasedCapital	1183932000	USD
CY2019Q4	us-gaap	Tier One Risk Based Capital To Risk Weighted Assets TierOneRiskBasedCapitalToRiskWeightedAssets	0.1230
CY2019Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy TierOneRiskBasedCapitalRequiredForCapitalAdequacy	577720000	USD
CY2019Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0600
CY2019Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	1183932000	USD
CY2019Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.0933
CY2019Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	385147000	USD
CY2019Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy To Average Assets TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets	0.0400
CY2018Q4	us-gaap	Capital Capital	1172120000	USD
CY2018Q4	us-gaap	Capital To Risk Weighted Assets CapitalToRiskWeightedAssets	0.1299
CY2018Q4	us-gaap	Capital Required For Capital Adequacy CapitalRequiredForCapitalAdequacy	721605000	USD
CY2018Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.0800
CY2018Q4	bhlb	Common Equity Tier One Risk Based Capitalto Risk Weighted Assets Amount CommonEquityTierOneRiskBasedCapitaltoRiskWeightedAssetsAmount	1029724000	USD
CY2018Q4	bhlb	Common Equity Tier One Risk Based Capital To Risk Weighted Assets CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets	0.1142
CY2018Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	1043898000	USD
CY2018Q4	us-gaap	Tier One Leverage Capital To Average Assets TierOneLeverageCapitalToAverageAssets	0.0904
CY2018Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy TierOneLeverageCapitalRequiredForCapitalAdequacy	360802000	USD
CY2018Q4	us-gaap	Tier One Leverage Capital Required For Capital Adequacy To Average Assets TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets	0.0400
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.29
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.39
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
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-16587000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-4313000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2018	bhlb	Total Change To Aoci Before Tax Attributable To Parent TotalChangeToAOCIBeforeTaxAttributableToParent	-24966000	USD
CY2018	bhlb	Total Change To Aoci Tax Attributable To Parent TotalChangeToAOCITaxAttributableToParent	-7335000	USD
CY2018	bhlb	Total Change To Aoci Net Of Tax Attributable To Parent TotalChangeToAOCINetOfTaxAttributableToParent	-17631000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-8663000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-3058000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-5605000	USD
CY2019	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	25507000	USD
CY2019	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	44000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	25463000	USD
CY2018	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-12417000	USD
CY2018	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-143000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-12274000	USD
CY2017	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-1925000	USD
CY2017	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	3680000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-5605000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	109219000	USD
CY2017	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	49116000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-3454000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	6131000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	55247000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	49782000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	46212000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	40627000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	1142000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	810000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Treasury Stock WeightedAverageNumberOfSharesTreasuryStock	963000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	420000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	421000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Restricted Stock WeightedAverageNumberOfSharesRestrictedStock	437000	shares
CY2019	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	1043000	shares
CY2018	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	1043000	shares
CY2017	bhlb	Weighted Average Numberof Shares Outstanding Preferred Stock WeightedAverageNumberofSharesOutstandingPreferredStock	229000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49263000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46024000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	39456000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49421000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46231000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	39695000	shares
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.06
CY2018	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.38
CY2017	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.24
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.08
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.08
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.16
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.30
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.40
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.05
CY2018	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.36
CY2017	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.24
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.08
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.07
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.15
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.97
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	44000000.0	USD
CY2018	bhlb	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 Number Of Transfers FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3NumberOfTransfers	0	transfer
CY2019	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	35000000	USD
CY2019Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	125441000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	133725000	USD
CY2019Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	129238000	USD
CY2019Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	121109000	USD
CY2018Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	126695000	USD
CY2018Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	117569000	USD
CY2018Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	115484000	USD
CY2018Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	106146000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	34108000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	36854000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	37643000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	35650000	USD
CY2018Q4	us-gaap	Interest Expense InterestExpense	33929000	USD
CY2018Q3	us-gaap	Interest Expense InterestExpense	29184000	USD
CY2018Q2	us-gaap	Interest Expense InterestExpense	25192000	USD
CY2018Q1	us-gaap	Interest Expense InterestExpense	21389000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91333000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	96871000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91595000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	85459000	USD
CY2018Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	92766000	USD
CY2018Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	88385000	USD
CY2018Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	90292000	USD
CY2018Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	84757000	USD
CY2019Q4	us-gaap	Noninterest Income NoninterestIncome	23362000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	21406000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	17512000	USD
CY2019Q1	us-gaap	Noninterest Income NoninterestIncome	21722000	USD
CY2018Q4	us-gaap	Noninterest Income NoninterestIncome	15775000	USD
CY2018Q3	us-gaap	Noninterest Income NoninterestIncome	20034000	USD
CY2018Q2	us-gaap	Noninterest Income NoninterestIncome	19623000	USD
CY2018Q1	us-gaap	Noninterest Income NoninterestIncome	18892000	USD
CY2019Q4	us-gaap	Revenues Revenues	114695000	USD
CY2019Q3	us-gaap	Revenues Revenues	118277000	USD
CY2019Q2	us-gaap	Revenues Revenues	109107000	USD
CY2019Q1	us-gaap	Revenues Revenues	107181000	USD
CY2018Q4	us-gaap	Revenues Revenues	108541000	USD
CY2018Q3	us-gaap	Revenues Revenues	108419000	USD
CY2018Q2	us-gaap	Revenues Revenues	109915000	USD
CY2018Q1	us-gaap	Revenues Revenues	103649000	USD
CY2019Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	5351000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	22600000	USD
CY2019Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3467000	USD
CY2019Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	4001000	USD
CY2018Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	6716000	USD
CY2018Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	6628000	USD
CY2018Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	6532000	USD
CY2018Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	5575000	USD
CY2019Q4	us-gaap	Noninterest Expense NoninterestExpense	70287000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	71011000	USD
CY2019Q2	us-gaap	Noninterest Expense NoninterestExpense	76568000	USD
CY2019Q1	us-gaap	Noninterest Expense NoninterestExpense	71991000	USD
CY2018Q4	us-gaap	Noninterest Expense NoninterestExpense	80373000	USD
CY2018Q3	us-gaap	Noninterest Expense NoninterestExpense	59627000	USD
CY2018Q2	us-gaap	Noninterest Expense NoninterestExpense	61527000	USD
CY2018Q1	us-gaap	Noninterest Expense NoninterestExpense	65366000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	39057000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	24666000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	29072000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	31189000	USD
CY2018Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	21452000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	42164000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	41856000	USD
CY2018Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	32708000	USD
CY2019Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6421000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4007000	USD
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	1494000	USD
CY2019Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-637000	USD
CY2018Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-2809000	USD
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-842000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	5118000	USD
CY2019Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6917000	USD
CY2018Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4384000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9095000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8145000	USD
CY2018Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7337000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	32636000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	20659000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	23954000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	24272000	USD
CY2018Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	17068000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	33069000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	33711000	USD
CY2018Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	25371000	USD
CY2019Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-6885000	USD
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	1957000	USD
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	320000	USD
CY2018Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-123000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	25751000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	22616000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	25448000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	23635000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	14259000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	32227000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	34031000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	25248000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.65
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.40
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.49
CY2019Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.52
CY2018Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.37
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.72
CY2018Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.73
CY2018Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.55
CY2019Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.14
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.04
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.51
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.44
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.03
CY2019Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.01
CY2018Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.06
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.02
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.01
CY2018Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.52
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.51
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.31
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.55
CY2019Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.65
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.40
CY2019Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.49
CY2019Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.52
CY2018Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.37
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.72
CY2018Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.73
CY2018Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.55
CY2019Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.14
CY2019Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.04
CY2019Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.03
CY2019Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.01
CY2018Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.06
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.02
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.01
CY2018Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.44
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.52
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.31
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.74
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.55
CY2019Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50494000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51422000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	48961000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46113000	shares
CY2018Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46061000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46030000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46032000	shares
CY2018Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	45966000	shares
CY2019Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50702000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51545000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49114000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46261000	shares
CY2018Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46240000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46263000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46215000	shares
CY2018Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46200000	shares
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	365258000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	356200000	USD
CY2017	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	290963000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	35419000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25451000	USD
CY2017	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	21025000	USD
CY2019	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	329839000	USD
CY2018	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	330749000	USD
CY2017	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	269938000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	74324000	USD
CY2017	us-gaap	Noninterest Income NoninterestIncome	74244000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	289857000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	266893000	USD
CY2017	us-gaap	Noninterest Expense NoninterestExpense	252978000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	123984000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	138180000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	91204000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22463000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	28961000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	42088000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	101521000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	109219000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	49116000	USD
CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-5539000	USD
CY2018	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	-4767000	USD
CY2017	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax	8545000	USD
CY2019	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1468000	USD
CY2018	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	-1313000	USD
CY2017	us-gaap	Discontinued Operation Tax Effect Of Discontinued Operation DiscontinuedOperationTaxEffectOfDiscontinuedOperation	2414000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-4071000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-3454000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	6131000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	97450000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	105765000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	55247000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	49698000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	48653000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	44954000	USD
CY2019	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	34304000	USD
CY2018	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	25671000	USD
CY2017	us-gaap	Revenue Not From Contract With Customer RevenueNotFromContractWithCustomer	29290000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	84002000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	74324000	USD
CY2017	us-gaap	Noninterest Income NoninterestIncome	74244000	USD

Files In Submission

Name	View Source	Status
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$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb

2019 Q4 Form 10-K Financial Statement

#000110813420000002 Filed on February 28, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BHLB BERKSHIRE HILLS BANCORP INC Stock $bhlb

2019 Q4 Form 10-K Financial Statement

#000110813420000002 Filed on February 28, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BHLB
BERKSHIRE HILLS BANCORP INC Stock $bhlb