$BFST
Business First Bancshares Inc Stock $bfst

$bfst Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000143774921005177 Filed on March 05, 2021

Income Statement

Concept	2019 Q4	2018	2017 Q4
Revenue		$76.20M
YoY Change		47.66%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$370.0K	$1.170M	$270.0K
YoY Change	15.63%	-0.85%	-20.59%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$13.97M
YoY Change		93.19%
% of Operating Profit
Other Income/Expense, Net		$4.156M
YoY Change		46.91%
Pretax Income	$7.490M	$17.37M	$1.020M
YoY Change	75.82%	94.06%	-49.0%
Income Tax	$1.730M	$3.279M	$220.0K
% Of Pretax Income	23.1%	18.88%	21.57%
Net Earnings	$5.760M	$14.09M	-$860.0K
YoY Change	66.96%	190.66%	-157.72%
Net Earnings / Revenue		18.49%
Basic Earnings Per Share		$1.27
Diluted Earnings Per Share	$421.7K	$1.22	-$112.3K
COMMON SHARES
Basic Shares Outstanding		11.12M	10.23M
Diluted Shares Outstanding		11.55M

Balance Sheet

Concept	2019 Q4	2018	2017 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$89.37M		$107.6M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$29.28M	$15.10M	$8.780M
YoY Change	93.73%	71.59%	-5.4%
Goodwill	$48.50M		$6.824M
YoY Change	-2.0%		0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$2.100M	$3.800M
YoY Change	-44.74%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$2.274B	$2.095B	$1.321B
YoY Change	8.54%	58.55%	19.48%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$1.500M	$1.400M	$900.0K
YoY Change	7.14%	55.56%	0.0%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$68.00M	$12.20M	$862.0K
YoY Change		335.71%	0.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$1.500M	$1.400M	$900.0K
YoY Change	7.14%	55.56%	0.0%
LONG-TERM LIABILITIES
Long-Term Debt	$25.00M	$25.00M	$2.700M
YoY Change	0.0%	825.93%	-10.0%
Other Long-Term Liabilities	$19.20M	$7.300M	$4.400M
YoY Change	163.01%	65.91%	-10.2%
Total Long-Term Liabilities	$44.20M	$32.30M	$7.100M
YoY Change	36.84%	354.93%	-10.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.500M	$1.400M	$900.0K
Total Long-Term Liabilities	$44.20M	$32.30M	$7.100M
Total Liabilities	$1.989B	$1.835B	$1.141B
YoY Change	8.39%	60.76%	15.02%
SHAREHOLDERS EQUITY
Retained Earnings	$56.70M		$27.18M
YoY Change	49.28%		13.99%
Common Stock	$225.8M		$154.4M
YoY Change	0.11%		67.74%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$285.1M	$260.1M	$179.9M
YoY Change
Total Liabilities & Shareholders Equity	$2.274B	$2.095B	$1.321B
YoY Change	8.54%	58.55%	19.48%

Cashflow Statement

Concept	2019 Q4	2018	2017 Q4
OPERATING ACTIVITIES
Net Income	$5.760M	$14.09M	-$860.0K
YoY Change	66.96%	190.66%	-157.72%
Depreciation, Depletion And Amortization	$370.0K	$1.170M	$270.0K
YoY Change	15.63%	-0.85%	-20.59%
Cash From Operating Activities	$2.920M	$19.28M	$810.0K
YoY Change	7.75%	141.92%	-45.27%
INVESTING ACTIVITIES
Capital Expenditures	-$1.930M	$919.0K	-$80.00K
YoY Change	1384.62%	81.98%	-11.11%
Acquisitions		$9.148M
YoY Change
Other Investing Activities	-$24.35M	-$169.4M	-$40.29M
YoY Change	-21.6%	10.76%	-917.24%
Cash From Investing Activities	-$26.27M	-$170.3M	-$40.37M
YoY Change	-15.77%	11.0%	-934.09%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		-$27.65M
YoY Change		-55.7%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	49.37M	$139.5M	110.9M
YoY Change	-37.2%	-33.84%	5157.82%
NET CHANGE
Cash From Operating Activities	2.920M	$19.28M	810.0K
Cash From Investing Activities	-26.27M	-$170.3M	-40.37M
Cash From Financing Activities	49.37M	$139.5M	110.9M
Net Change In Cash	26.02M	-$11.52M	71.38M
YoY Change	-48.09%	-117.61%	746.74%
FREE CASH FLOW
Cash From Operating Activities	$2.920M	$19.28M	$810.0K
Capital Expenditures	-$1.930M	$919.0K	-$80.00K
Free Cash Flow	$4.850M	$18.36M	$890.0K
YoY Change	70.77%	145.97%	-43.31%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019Q4	bfst	Reserve Requirements With Federal Reserve ReserveRequirementsWithFederalReserve	0	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	pure
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CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-7000	USD
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	2131000	USD
CY2019	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	1616000	USD
CY2018	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	-485000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	8015000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	6082000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1825000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	38009000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	29854000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	12266000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	179935000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	14091000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1825000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	3281000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	70128000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	1099000	USD
CY2018	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	89000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	260058000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	23772000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	6082000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	5054000	USD
CY2019	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	1699000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	1301000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation Forfeited StockIssuedDuringPeriodValueShareBasedCompensationForfeited	208000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2553000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	285097000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	29994000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	8015000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	7520000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	102044000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	2453000	USD
CY2020	bfst	Stock Surrended Of Options Exercised StockSurrendedOfOptionsExercised	4321000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	5799000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	409963000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	29994000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	23772000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	14091000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11435000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2606000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2390000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	3164000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1588000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1172000	USD
CY2020	bfst	Business Acquisition Amortization Accretion Fair Market Value Adjustments BusinessAcquisitionAmortizationAccretionFairMarketValueAdjustments	-7283000	USD
CY2019	bfst	Business Acquisition Amortization Accretion Fair Market Value Adjustments BusinessAcquisitionAmortizationAccretionFairMarketValueAdjustments	-2646000	USD
CY2018	bfst	Business Acquisition Amortization Accretion Fair Market Value Adjustments BusinessAcquisitionAmortizationAccretionFairMarketValueAdjustments	-719000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	2453000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	1093000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	1010000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-5136000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1688000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2038000	USD
CY2020	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	135000	USD
CY2019	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	106000	USD
CY2018	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	7000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	2658000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	1684000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	334000	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	30000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-546000	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	14000	USD
CY2020	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	940000	USD
CY2019	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	686000	USD
CY2018	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	681000	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-58000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	336000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-402000	USD
CY2020	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-0	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	581000	USD
CY2018	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-0	USD
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	10648000	USD
CY2019	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-198000	USD
CY2018	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	970000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2655000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	318000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-1275000	USD
CY2020	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-1694000	USD
CY2019	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	159000	USD
CY2018	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	184000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	3258000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-1547000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	243000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	29339000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	24418000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	19276000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	233566000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	27223000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	16106000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	66779000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	25984000	USD
CY2020	us-gaap	Proceeds From Repayments Of Secured Debt ProceedsFromRepaymentsOfSecuredDebt	-1797000	USD
CY2019	us-gaap	Proceeds From Repayments Of Secured Debt ProceedsFromRepaymentsOfSecuredDebt	0	USD
CY2018	us-gaap	Proceeds From Repayments Of Secured Debt ProceedsFromRepaymentsOfSecuredDebt	-2700000	USD
CY2020	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	11417000	USD
CY2020	bfst	Proceeds From Repayments Of Investment Securities Available For Sale ProceedsFromRepaymentsOfInvestmentSecuritiesAvailableForSale	73890000	USD
CY2019	bfst	Proceeds From Repayments Of Investment Securities Available For Sale ProceedsFromRepaymentsOfInvestmentSecuritiesAvailableForSale	38678000	USD
CY2018	bfst	Proceeds From Repayments Of Investment Securities Available For Sale ProceedsFromRepaymentsOfInvestmentSecuritiesAvailableForSale	33670000	USD
CY2020	bfst	Cash Acquired From Paid For Acquisition CashAcquiredFromPaidForAcquisition	106000000	USD
CY2019	bfst	Cash Acquired From Paid For Acquisition CashAcquiredFromPaidForAcquisition	0	USD
CY2018	bfst	Cash Acquired From Paid For Acquisition CashAcquiredFromPaidForAcquisition	-9148000	USD
CY2020	bfst	Payments To Sell Branch Net PaymentsToSellBranchNet	-0	USD
CY2019	bfst	Payments To Sell Branch Net PaymentsToSellBranchNet	17448000	USD
CY2018	bfst	Payments To Sell Branch Net PaymentsToSellBranchNet	-0	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	681000	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	3031000	USD
CY2018	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	1175000	USD
CY2020	bfst	Redemption Of Other Equity Securities RedemptionOfOtherEquitySecurities	8577000	USD
CY2019	bfst	Redemption Of Other Equity Securities RedemptionOfOtherEquitySecurities	1432000	USD
CY2018	bfst	Redemption Of Other Equity Securities RedemptionOfOtherEquitySecurities	3176000	USD
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	384962000	USD
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	189361000	USD
CY2018	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	168371000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2970000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	3959000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	919000	USD
CY2020	bfst	Loss On Disposal Of Property Plant And Equipment LossOnDisposalOfPropertyPlantAndEquipment	576000	USD
CY2019	bfst	Loss On Disposal Of Property Plant And Equipment LossOnDisposalOfPropertyPlantAndEquipment	774000	USD
CY2018	bfst	Loss On Disposal Of Property Plant And Equipment LossOnDisposalOfPropertyPlantAndEquipment	0	USD
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	3842000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	1400000	USD
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	654000	USD
CY2020	us-gaap	Increase Decrease In Federal Funds Sold IncreaseDecreaseInFederalFundsSold	-112780000	USD
CY2019	us-gaap	Increase Decrease In Federal Funds Sold IncreaseDecreaseInFederalFundsSold	-19536000	USD
CY2018	us-gaap	Increase Decrease In Federal Funds Sold IncreaseDecreaseInFederalFundsSold	-23516000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-475295000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-192290000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-170318000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	658388000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	73319000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	124471000	USD
CY2020	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-48767000	USD
CY2019	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	55760000	USD
CY2018	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-5757000	USD
CY2020	bfst	Net Repayments Advances Of Federal Home Loan Bank Borrowings NetRepaymentsAdvancesOfFederalHomeLoanBankBorrowings	-89198000	USD
CY2019	bfst	Net Repayments Advances Of Federal Home Loan Bank Borrowings NetRepaymentsAdvancesOfFederalHomeLoanBankBorrowings	38000000	USD
CY2018	bfst	Net Repayments Advances Of Federal Home Loan Bank Borrowings NetRepaymentsAdvancesOfFederalHomeLoanBankBorrowings	-25000000	USD
CY2020	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	1369000	USD
CY2019	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	0	USD
CY2018	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	-862000	USD
CY2019	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	25000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	3361000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	823000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	27652000	USD
CY2020	bfst	Payments For Surrendered Shares Of Options Exercised PaymentsForSurrenderedSharesOfOptionsExercised	4321000	USD
CY2019	bfst	Payments For Surrendered Shares Of Options Exercised PaymentsForSurrenderedSharesOfOptionsExercised	-0	USD
CY2018	bfst	Payments For Surrendered Shares Of Options Exercised PaymentsForSurrenderedSharesOfOptionsExercised	-0	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	5799000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	2553000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	-0	USD
CY2020	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	0	USD
CY2019	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	876000	USD
CY2018	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	0	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	7520000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	5054000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	3281000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	505716000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	161171000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	139523000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	59760000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-6701000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-11519000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	89371000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	96072000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	107591000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	149131000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	89371000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	96072000	USD
CY2020	bfst	Interest On Deposits InterestOnDeposits	16589000	USD
CY2019	bfst	Interest On Deposits InterestOnDeposits	19616000	USD
CY2018	bfst	Interest On Deposits InterestOnDeposits	11384000	USD
CY2020	bfst	Interest Paid On Borrowings Net InterestPaidOnBorrowingsNet	4554000	USD
CY2019	bfst	Interest Paid On Borrowings Net InterestPaidOnBorrowingsNet	3494000	USD
CY2018	bfst	Interest Paid On Borrowings Net InterestPaidOnBorrowingsNet	2098000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	5470000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	5600000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	3342000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	9918000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	7698000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-2310000	USD
CY2020	bfst	Oci Equity Securities Availableforsale Unrealized Holding Gain Loss Before Adjustment And Tax OciEquitySecuritiesAvailableforsaleUnrealizedHoldingGainLossBeforeAdjustmentAndTax	228000	USD
CY2019	bfst	Oci Equity Securities Availableforsale Unrealized Holding Gain Loss Before Adjustment And Tax OciEquitySecuritiesAvailableforsaleUnrealizedHoldingGainLossBeforeAdjustmentAndTax	0	USD
CY2018	bfst	Oci Equity Securities Availableforsale Unrealized Holding Gain Loss Before Adjustment And Tax OciEquitySecuritiesAvailableforsaleUnrealizedHoldingGainLossBeforeAdjustmentAndTax	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-2131000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-1616000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	485000	USD
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	1506000	USD
CY2019	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	4102000	USD
CY2018	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	395000	USD
CY2020	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	5900000	USD
CY2019	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	0	USD
CY2018	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	1373000	USD
CY2020	bfst	Noncash Or Part Noncash Acquisition Identifiable Assets Acquired NoncashOrPartNoncashAcquisitionIdentifiableAssetsAcquired	1330940000	USD
CY2019	bfst	Noncash Or Part Noncash Acquisition Identifiable Assets Acquired NoncashOrPartNoncashAcquisitionIdentifiableAssetsAcquired	0	USD
CY2018	bfst	Noncash Or Part Noncash Acquisition Identifiable Assets Acquired NoncashOrPartNoncashAcquisitionIdentifiableAssetsAcquired	627429000	USD
CY2020	us-gaap	Noncash Or Part Noncash Acquisition Intangible Assets Acquired1 NoncashOrPartNoncashAcquisitionIntangibleAssetsAcquired1	4211000	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Intangible Assets Acquired1 NoncashOrPartNoncashAcquisitionIntangibleAssetsAcquired1	0	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Intangible Assets Acquired1 NoncashOrPartNoncashAcquisitionIntangibleAssetsAcquired1	6441000	USD
CY2020	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	1241834000	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	0	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1 NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1	577909000	USD
CY2020	bfst	Noncash Or Part Noncash Acquisition Assets Acquired Liabilities Assumed NoncashOrPartNoncashAcquisitionAssetsAcquiredLiabilitiesAssumed	93317000	USD
CY2019	bfst	Noncash Or Part Noncash Acquisition Assets Acquired Liabilities Assumed NoncashOrPartNoncashAcquisitionAssetsAcquiredLiabilitiesAssumed	0	USD
CY2018	bfst	Noncash Or Part Noncash Acquisition Assets Acquired Liabilities Assumed NoncashOrPartNoncashAcquisitionAssetsAcquiredLiabilitiesAssumed	55961000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;"><span style="text-decoration: underline; ">Estimates</span></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;"> </p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;">Preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying disclosures. These estimates are based on management’s best knowledge of current events and actions the Company <em style="font: inherit;"> may </em>undertake in the future. Estimates are used in accounting for, among other items, the allowance for loan losses, useful lives for depreciation and amortization, goodwill, fair value of financial instruments, taxes, and contingencies. Estimates that are particularly susceptible to significant change for the Company include the determination of the allowance for loan losses, accounting for business combinations, goodwill, and the assessment of income taxes, and therefore are critical accounting policies. Management does <em style="font: inherit;">not</em> anticipate any material changes to estimates in the near term. Factors that <em style="font: inherit;"> may </em>cause sensitivity to the aforementioned estimates include but are <em style="font: inherit;">not</em> limited to: external market factors such as market interest rates and employment rates, changes to operating policies and procedures, economic conditions in our markets, and changes in applicable banking regulations. Actual results <em style="font: inherit;"> may </em>ultimately differ from estimates.</p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;"><b> </b></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;">The Bank’s loans are generally secured by specific items of collateral including real property, business assets, and consumer assets. Although the Bank has a diversified loan portfolio, a substantial portion of its debtors’ ability to honor their contracts is dependent on local economic conditions in the Bank’s market area.</p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;"><b> </b></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;">While management uses available information to recognize losses on loans, further reductions in the carrying amounts of loans <em style="font: inherit;"> may </em>be necessary based on changes in local economic conditions. In addition, regulatory agencies, as an integral part of their examination process, periodically review the estimated losses on loans. Such agencies <em style="font: inherit;"> may </em>require the Bank to recognize additional losses based on their judgments about information available to them at the time of their examination.</p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;"> </p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;">Because of these factors, it is reasonably possible that the estimated losses on loans <em style="font: inherit;"> may </em>change materially in the near term. However, the amount of the change that is reasonably possible cannot be estimated.</p>
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	0	USD
CY2019Q4	us-gaap	Trading Securities TradingSecurities	0	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	1600000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	1500000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	1200000	USD
CY2020	us-gaap	Reclassifications Reclassifications	<p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:justify;"><b>Note <em style="font: inherit;">2</em> – Reclassifications –</b></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:justify;"> </p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;">Certain reclassifications <em style="font: inherit;"> may </em>have been made to the prior years’ financial statements in order to conform to the classifications adopted for reporting in <em style="font: inherit;">2020.</em> These reclassifications have <em style="font: inherit;">no</em> material effect on previously reported net income.</p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;"><b/></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;"><b/></p><p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:justify;"><b/></p>
CY2020	us-gaap	Net Income Loss NetIncomeLoss	29994000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	23772000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	14091000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	18169599
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	13310577
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	11124585
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	73846
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	360200
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	421358
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	18243445
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	13670777
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	11545943
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.65
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.79
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.27
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.64
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.74
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.22
CY2020Q4	bfst	Reserve Requirements With Federal Reserve ReserveRequirementsWithFederalReserve	0	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	627380000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	13583000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	358000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	640605000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	274886000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	3987000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	680000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	278193000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	68096000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	357000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	17000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	68113000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	358000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	4384000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	28000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	51987000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	652000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	1698141000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	22024000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12124000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	2969331000	USD
CY2020Q4	bfst	Loans Receivable Unpaid Principal Balance LoansReceivableUnpaidPrincipalBalance	430000000.0	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	56371000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	680000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis	18725000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Fair Value AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	18814000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis	122929000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	125050000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis	294048000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	300897000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis	191678000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue	195844000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	627380000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	640605000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	301700000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	165900000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	293000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	112000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	7000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	158000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	6000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2991355000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	1710265000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	10200000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	3000000.0	USD
CY2020Q4	bfst	Loans And Leases Receivable Reclassified From Overdraft LoansAndLeasesReceivableReclassifiedFromOverdraft	623000	USD
CY2019Q4	bfst	Loans And Leases Receivable Reclassified From Overdraft LoansAndLeasesReceivableReclassifiedFromOverdraft	276000	USD
CY2019Q4	bfst	Loans Receivable Unpaid Principal Balance LoansReceivableUnpaidPrincipalBalance	129700000	USD
CY2020Q4	us-gaap	Servicing Asset ServicingAsset	1400000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12124000	USD
CY2020	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1963000	USD
CY2020	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	428000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11435000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	22024000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	1014000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	21010000	USD
CY2020Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Allowance For Loan Losses CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAllowanceForLoanLosses	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2991355000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	19976000	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	2907119000	USD
CY2020Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Carrying Amount Net CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesCarryingAmountNet	64260000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	11220000	USD
CY2019	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1825000	USD
CY2019	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	123000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2606000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12124000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	556000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	11568000	USD
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Allowance For Loan Losses CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAllowanceForLoanLosses	0	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	1710265000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	11847000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	1693409000	USD
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Carrying Amount Net CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesCarryingAmountNet	5009000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2991355000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	1710265000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	1500000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	72000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	9100000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	9000000.0	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	20481000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	2970874000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2991355000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	1523000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	8789000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	1701476000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	1710265000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	72000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	9063000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	8977000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	516000	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	292000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	3593000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	3738000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	1014000	USD
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	2855000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	16383000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	18097000	USD
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	15912000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	19976000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	21835000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	1014000	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	18767000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	1848000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	1975000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	556000	USD
CY2019	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	1955000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	9999000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	11892000	USD
CY2019	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	10885000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	11847000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	13867000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	556000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	12840000	USD
CY2020Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period Contractually Required Payments Receivable At Acquisition CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAcquiredDuringPeriodContractuallyRequiredPaymentsReceivableAtAcquisition	133621000	USD
CY2020Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Allowance For Loan Losses CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAllowanceForLoanLosses	49828000	USD
CY2020Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period Cash Flows Expected To Be Collected At Acquisition CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAcquiredDuringPeriodCashFlowsExpectedToBeCollectedAtAcquisition	83793000	USD
CY2020Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	-9202000	USD
CY2020Q2	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period At Acquisition At Fair Value CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAcquiredDuringPeriodAtAcquisitionAtFairValue	74591000	USD
CY2019Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	1489000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	9202000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Reclassifications From Nonaccretable Difference CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldReclassificationsFromNonaccretableDifference	4762000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Accretion CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAccretion	2801000	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Period Increase Decrease CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldPeriodIncreaseDecrease	3201000	USD
CY2020Q4	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYield	15853000	USD
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CY2020Q4	bfst	Financing Receivable Accrued Interest Receivable Loans Deferrals FinancingReceivableAccruedInterestReceivableLoansDeferrals	8400000	USD
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CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	58593000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	29280000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	3200000	USD
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CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1200000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	53900000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	48500000	USD
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CY2020Q4	bfst	Deposits Public Funds Non Brokered DepositsPublicFundsNonBrokered	382400000	USD
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CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6080000	USD
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CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	406000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	151000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	143000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6080000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3279000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	1235000	USD
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CY2020Q4	bfst	Deferred Tax Assets Acquired Loans Fair Market Value Adjustment DeferredTaxAssetsAcquiredLoansFairMarketValueAdjustment	7472000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	17276000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	7560000	USD
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CY2019Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	43000	USD
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CY2020Q4	us-gaap	Tier One Leverage Capital TierOneLeverageCapital	340715000	USD
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CY2019Q4	us-gaap	Capital Capital	264495000	USD
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CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	0
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	2000
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	17.11
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	385300
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	14.67
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	725300
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	12.55
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	780080
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	12.74
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	385300
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	14.67
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	724300
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	12.55
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	761747
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	12.64
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber	385300
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice	14.67
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares	0
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	2200000	USD
CY2019Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	9000000.0	USD
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P1Y7M6D
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P1Y4M24D
CY2017Q4	bfst	Share Based Compensation Arrangement By Share Based Payment Award Options Amended Number Of Shares ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAmendedNumberOfShares	105250
CY2017Q4	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	63000	USD
CY2016Q4	bfst	Share Based Compensation Arrangement By Share Based Payment Award Options Amended Number Of Shares ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAmendedNumberOfShares	330000
CY2020	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.04	pure
CY2020	bfst	Employee Compensation And Benefits EmployeeCompensationAndBenefits	1400000	USD
CY2019	bfst	Employee Compensation And Benefits EmployeeCompensationAndBenefits	967000	USD
CY2018	bfst	Employee Compensation And Benefits EmployeeCompensationAndBenefits	690000	USD
CY2020Q4	us-gaap	Deferred Compensation Arrangement With Individual Recorded Liability DeferredCompensationArrangementWithIndividualRecordedLiability	2700000	USD
CY2019Q4	us-gaap	Deferred Compensation Arrangement With Individual Recorded Liability DeferredCompensationArrangementWithIndividualRecordedLiability	2500000	USD
CY2020	us-gaap	Deferred Compensation Arrangement With Individual Compensation Expense DeferredCompensationArrangementWithIndividualCompensationExpense	285000	USD
CY2019	us-gaap	Deferred Compensation Arrangement With Individual Compensation Expense DeferredCompensationArrangementWithIndividualCompensationExpense	256000	USD
CY2018	us-gaap	Deferred Compensation Arrangement With Individual Compensation Expense DeferredCompensationArrangementWithIndividualCompensationExpense	224000	USD
CY2020	bfst	Bank Regulatory Expenses BankRegulatoryExpenses	1785000	USD
CY2019	bfst	Bank Regulatory Expenses BankRegulatoryExpenses	389000	USD
CY2018	bfst	Bank Regulatory Expenses BankRegulatoryExpenses	1359000	USD
CY2020	us-gaap	Taxes And Licenses TaxesAndLicenses	84000	USD
CY2019	us-gaap	Taxes And Licenses TaxesAndLicenses	88000	USD
CY2018	us-gaap	Taxes And Licenses TaxesAndLicenses	201000	USD
CY2020	us-gaap	Business Development BusinessDevelopment	1605000	USD
CY2019	us-gaap	Business Development BusinessDevelopment	1535000	USD
CY2018	us-gaap	Business Development BusinessDevelopment	1239000	USD
CY2020	us-gaap	Communication Communication	1969000	USD
CY2019	us-gaap	Communication Communication	1063000	USD
CY2018	us-gaap	Communication Communication	885000	USD
CY2020	bfst	Ad Valorem Shares Tax AdValoremSharesTax	2348000	USD
CY2019	bfst	Ad Valorem Shares Tax AdValoremSharesTax	1423000	USD
CY2018	bfst	Ad Valorem Shares Tax AdValoremSharesTax	1135000	USD
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	5506000	USD
CY2019	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	2049000	USD
CY2018	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	1557000	USD
CY2020	us-gaap	Noninterest Expense Directors Fees NoninterestExpenseDirectorsFees	464000	USD
CY2019	us-gaap	Noninterest Expense Directors Fees NoninterestExpenseDirectorsFees	570000	USD
CY2018	us-gaap	Noninterest Expense Directors Fees NoninterestExpenseDirectorsFees	436000	USD
CY2020	us-gaap	General Insurance Expense GeneralInsuranceExpense	718000	USD
CY2019	us-gaap	General Insurance Expense GeneralInsuranceExpense	347000	USD
CY2018	us-gaap	General Insurance Expense GeneralInsuranceExpense	256000	USD
CY2020	us-gaap	Professional Fees ProfessionalFees	2118000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	1319000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	1695000	USD
CY2020	us-gaap	Supplies Expense SuppliesExpense	884000	USD
CY2019	us-gaap	Supplies Expense SuppliesExpense	670000	USD
CY2018	us-gaap	Supplies Expense SuppliesExpense	578000	USD
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3978000	USD
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3024000	USD
CY2020	us-gaap	Other Expenses OtherExpenses	10760000	USD
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	330000	USD
CY2019	us-gaap	Other Expenses OtherExpenses	5911000	USD
CY2018	us-gaap	Other Expenses OtherExpenses	4156000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	32219000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	15694000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	16521000	USD
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	2600000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	2900000	USD
CY2018	us-gaap	Operating Lease Expense OperatingLeaseExpense	2500000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y9M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y3M18D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0289	pure
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0310	pure
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	2159000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	1977000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	1869000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	1672000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	1548000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	5254000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	14479000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	1547000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	33200000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	24600000	USD
CY2020Q4	us-gaap	Related Party Deposit Liabilities RelatedPartyDepositLiabilities	40200000	USD
CY2019Q4	us-gaap	Related Party Deposit Liabilities RelatedPartyDepositLiabilities	34400000	USD
CY2020	us-gaap	Loss Contingency Disclosures LossContingencyDisclosures	<p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;"><b>Note <em style="font: inherit;">2</em></b><b><em style="font: inherit;">5</em></b><b> – Litigation and Contingencies –</b></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;"> </p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin-bottom:0pt;margin-left:14.4pt;margin-right:0pt;margin-top:0pt;text-align:justify;">In the normal course of business, the Bank is involved in various legal proceedings. In the opinion of management and counsel, the disposition or ultimate resolution of such proceedings would <em style="font: inherit;">not</em> have a material adverse effect on the Bank’s financial statements.</p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;"><b> </b></p> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;"> </p>

Files In Submission

Name	View Source	Status
0001437749-21-005177-index-headers.html	Edgar Link	pending
0001437749-21-005177-index.html	Edgar Link	pending
0001437749-21-005177.txt	Edgar Link	pending
0001437749-21-005177-xbrl.zip	Edgar Link	pending
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2019 Q4 Form 10-K Financial Statement

#000143774921005177 Filed on March 05, 2021

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$BFST Business First Bancshares Inc Stock $bfst

2019 Q4 Form 10-K Financial Statement

#000143774921005177 Filed on March 05, 2021

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Files In Submission

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