$FNRN
FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn

$fnrn Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000114036121007530 Filed on March 08, 2021

Income Statement

Concept	2020 Q4	2019 Q4	2019
Revenue			$48.99M
YoY Change			7.4%
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	$220.0K	$210.0K	$721.0K
YoY Change	4.76%	50.0%	27.61%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense			$1.859M
YoY Change			46.61%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$4.600M	$5.000M	$20.39M
YoY Change	-8.0%	9.89%	17.9%
Income Tax	$1.250M	$1.430M	$5.670M
% Of Pretax Income	27.17%	28.6%	27.81%
Net Earnings	$3.350M	$3.580M	$14.72M
YoY Change	-6.42%	6.87%	17.29%
Net Earnings / Revenue			30.05%
Basic Earnings Per Share			$1.10
Diluted Earnings Per Share	$195.4K	$250.7K	$1.08
COMMON SHARES
Basic Shares Outstanding		12.30M	13.41M
Diluted Shares Outstanding			13.58M

Balance Sheet

Concept	2020 Q4	2019 Q4	2019
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$267.2M	$111.5M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$6.513M	$6.594M	$13.60M
YoY Change	-1.23%	-0.78%	106.06%
Goodwill
YoY Change
Intangibles	$0.00
YoY Change
Long-Term Investments
YoY Change
Other Assets			$3.500M
YoY Change			-41.67%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$1.655B	$1.293B	$1.293B
YoY Change	28.07%	3.42%	3.42%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$15.10M	$13.60M	$13.60M
YoY Change	11.03%	6.25%	6.25%
Accrued Expenses	$6.500M	$7.500M	$7.500M
YoY Change	-13.33%
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$21.60M	$21.10M	$21.10M
YoY Change	2.37%	64.84%	64.84%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$0.00	$0.00	$0.00
YoY Change
TOTAL LIABILITIES
Total Short-Term Liabilities	$21.60M	$21.10M	$21.10M
Total Long-Term Liabilities	$0.00	$0.00	$0.00
Total Liabilities	$1.505B	$1.160B	$1.160B
YoY Change	29.75%	1.96%	1.96%
SHAREHOLDERS EQUITY
Retained Earnings	$37.12M	$31.62M
YoY Change	17.39%	32.28%
Common Stock	$108.5M	$101.2M
YoY Change	7.26%	8.09%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$150.7M	$132.9M	$132.9M
YoY Change
Total Liabilities & Shareholders Equity	$1.655B	$1.293B	$1.293B
YoY Change	28.07%	3.42%	3.42%

Cashflow Statement

Concept	2020 Q4	2019 Q4	2019
OPERATING ACTIVITIES
Net Income	$3.350M	$3.580M	$14.72M
YoY Change	-6.42%	6.87%	17.29%
Depreciation, Depletion And Amortization	$220.0K	$210.0K	$721.0K
YoY Change	4.76%	50.0%	27.61%
Cash From Operating Activities	-$1.650M	$6.300M	$16.56M
YoY Change	-126.19%	129.93%	5.64%
INVESTING ACTIVITIES
Capital Expenditures	-$20.00K	-$420.0K	$1.056M
YoY Change	-95.24%	-46.84%	9.66%
Acquisitions
YoY Change
Other Investing Activities	$18.94M	-$31.19M	-$34.16M
YoY Change	-160.72%	21.55%	-52.24%
Cash From Investing Activities	$18.92M	-$31.60M	-$35.21M
YoY Change	-159.87%	19.47%	-51.43%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$96.00K
YoY Change			5.49%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-25.74M	700.0K	14.11M
YoY Change	-3777.14%	775.0%	-29.29%
NET CHANGE
Cash From Operating Activities	-1.650M	6.300M	16.56M
Cash From Investing Activities	18.92M	-31.60M	-35.21M
Cash From Financing Activities	-25.74M	700.0K	14.11M
Net Change In Cash	-8.470M	-24.60M	-4.539M
YoY Change	-65.57%	4.1%	-87.69%
FREE CASH FLOW
Cash From Operating Activities	-$1.650M	$6.300M	$16.56M
Capital Expenditures	-$20.00K	-$420.0K	$1.056M
Free Cash Flow	-$1.630M	$6.720M	$15.51M
YoY Change	-124.26%	90.37%	5.38%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001114927
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020Q4	us-gaap	Debt Securities Available For Sale Restriction Type Extensible List DebtSecuritiesAvailableForSaleRestrictionTypeExtensibleList	us-gaap:CollateralPledgedMember
CY2019Q4	us-gaap	Debt Securities Available For Sale Restriction Type Extensible List DebtSecuritiesAvailableForSaleRestrictionTypeExtensibleList	us-gaap:CollateralPledgedMember
CY2019Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	fnrn:InterestPayableAndOtherLiabilities
CY2020Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	fnrn:InterestPayableAndOtherLiabilities
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	000-30707
CY2020	dei	Entity Registrant Name EntityRegistrantName	First Northern Community Bancorp
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	CA
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	68-0450397
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	195 N First St.
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Dixon
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	95620
CY2020	dei	City Area Code CityAreaCode	707
CY2020	dei	Local Phone Number LocalPhoneNumber	678-3041
CY2020	dei	Security12g Title Security12gTitle	Common Stock, no par value
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Non-accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	true
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Entity Shell Company EntityShellCompany	false
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CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	0
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CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
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CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.10
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CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-1000
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-6000
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	211000
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-2000
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-14000
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	280000
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	85000
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-82000
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	694000
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	213000
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-205000
CY2020	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansTax	15000
CY2019	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansTax	17000
CY2018	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansTax	-10000
CY2020	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	37000
CY2019	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	45000
CY2018	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-26000
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	1978000
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	2086000
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-257000
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4904000
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	5170000
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	11912000
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	100044000
CY2018	us-gaap	Net Income Loss NetIncomeLoss	12551000
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-639000
CY2018	fnrn	Dividends Common Stock Adjustments DividendsCommonStockAdjustments	0
CY2018	fnrn	Common Stock Dividend CommonStockDividend	0
CY2018	fnrn	Cash Paid In Lieu Of Fractional Shares CashPaidInLieuOfFractionalShares	10000
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	424000
CY2018	fnrn	Stock Issued During Period Value Restricted Stock Award And Employee Stock Purchase Plan Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardAndEmployeeStockPurchasePlanNetOfForfeitures	91000
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	0
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	112461000
CY2019	us-gaap	Net Income Loss NetIncomeLoss	14721000
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	5170000
CY2019	fnrn	Dividends Common Stock Adjustments DividendsCommonStockAdjustments	0
CY2019	fnrn	Common Stock Dividend CommonStockDividend	0
CY2019	fnrn	Cash Paid In Lieu Of Fractional Shares CashPaidInLieuOfFractionalShares	8000
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	475000
CY2019	fnrn	Stock Issued During Period Value Restricted Stock Award And Employee Stock Purchase Plan Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardAndEmployeeStockPurchasePlanNetOfForfeitures	96000
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	132915000
CY2020	us-gaap	Net Income Loss NetIncomeLoss	12161000
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4904000
CY2020	fnrn	Dividends Common Stock Adjustments DividendsCommonStockAdjustments	0
CY2020	fnrn	Common Stock Dividend CommonStockDividend	0
CY2020	fnrn	Cash Paid In Lieu Of Fractional Shares CashPaidInLieuOfFractionalShares	8000
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	574000
CY2020	fnrn	Stock Issued During Period Value Restricted Stock Award And Employee Stock Purchase Plan Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardAndEmployeeStockPurchasePlanNetOfForfeitures	111000
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	0
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	150657000
CY2020	us-gaap	Net Income Loss NetIncomeLoss	12161000
CY2019	us-gaap	Net Income Loss NetIncomeLoss	14721000
CY2018	us-gaap	Net Income Loss NetIncomeLoss	12551000
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3050000
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2100000
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	574000
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	475000
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	424000
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	943000
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	721000
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	565000
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2010000
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1683000
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2530000
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	296000
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-3000
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-20000
CY2020	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	2247000
CY2019	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	614000
CY2018	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	337000
CY2020	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	0
CY2019	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	308000
CY2018	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	0
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	281000
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1429000
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	450000
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1210000
CY2019	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	137000
CY2018	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	328000
CY2020	fnrn	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	1270000
CY2019	fnrn	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	865000
CY2018	fnrn	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	0
CY2020	fnrn	Increase Decrease In Accrued Interest Receivable And Other Assets IncreaseDecreaseInAccruedInterestReceivableAndOtherAssets	2837000
CY2018	fnrn	Proceeds From Payments For Federal Home Loan Bank Stock And Other Equity Securities ProceedsFromPaymentsForFederalHomeLoanBankStockAndOtherEquitySecurities	-452000
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	112559000
CY2020	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	386000
CY2019	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	0
CY2018	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	0
CY2020	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	79013000
CY2019	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	33796000
CY2018	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	21966000
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	81826000
CY2019	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	35017000
CY2018	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	22884000
CY2020	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	2552000
CY2019	fnrn	Increase Decrease In Accrued Interest Receivable And Other Assets IncreaseDecreaseInAccruedInterestReceivableAndOtherAssets	768000
CY2018	fnrn	Increase Decrease In Accrued Interest Receivable And Other Assets IncreaseDecreaseInAccruedInterestReceivableAndOtherAssets	596000
CY2020	fnrn	Increase Decrease In Interest Payable And Other Liabilities IncreaseDecreaseInInterestPayableAndOtherLiabilities	-734000
CY2019	fnrn	Increase Decrease In Interest Payable And Other Liabilities IncreaseDecreaseInInterestPayableAndOtherLiabilities	85000
CY2018	fnrn	Increase Decrease In Interest Payable And Other Liabilities IncreaseDecreaseInInterestPayableAndOtherLiabilities	222000
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	12590000
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	16564000
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	15679000
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	41995000
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	47955000
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	23860000
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	14201000
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	20796000
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	2487000
CY2020	fnrn	Proceeds From Principal Repayments Of Available For Sale Securities ProceedsFromPrincipalRepaymentsOfAvailableForSaleSecurities	66784000
CY2019	fnrn	Proceeds From Principal Repayments Of Available For Sale Securities ProceedsFromPrincipalRepaymentsOfAvailableForSaleSecurities	50781000
CY2018	fnrn	Proceeds From Principal Repayments Of Available For Sale Securities ProceedsFromPrincipalRepaymentsOfAvailableForSaleSecurities	50186000
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	208969000
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	141862000
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	114198000
CY2020	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-2223000
CY2019	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-7105000
CY2018	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-5611000
CY2020	fnrn	Proceeds From Payments For Federal Home Loan Bank Stock And Other Equity Securities ProceedsFromPaymentsForFederalHomeLoanBankStockAndOtherEquitySecurities	94000
CY2019	fnrn	Proceeds From Payments For Federal Home Loan Bank Stock And Other Equity Securities ProceedsFromPaymentsForFederalHomeLoanBankStockAndOtherEquitySecurities	-555000
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	5617000
CY2018	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	27801000
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	862000
CY2018	fnrn	Cash Dividends Paid In Lieu Of Fractional Shares CashDividendsPaidInLieuOfFractionalShares	10000
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	111000
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	96000
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	91000
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	344633000
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	14108000
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	116032000
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1056000
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	963000
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	668000
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	0
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	784000
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	0
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-201539000
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-35211000
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-72492000
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	339530000
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	14020000
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	19872000
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	5000000
CY2019	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	0
CY2018	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	0
CY2020	fnrn	Cash Dividends Paid In Lieu Of Fractional Shares CashDividendsPaidInLieuOfFractionalShares	8000
CY2019	fnrn	Cash Dividends Paid In Lieu Of Fractional Shares CashDividendsPaidInLieuOfFractionalShares	8000
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	19953000
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	155684000
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-4539000
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-36860000
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	111493000
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	116032000
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	152892000
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	267177000
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	111493000
CY2020	fnrn	Contractually Past Due Period After Which Accrual Of Interest On Loans Is Discontinued ContractuallyPastDuePeriodAfterWhichAccrualOfInterestOnLoansIsDiscontinued	P90D
CY2019Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	0
CY2020Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	0
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	0
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.2022
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.1210
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.1000
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.1001
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P3Y11M15D
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P5Y6M
CY2020	us-gaap	Advertising Expense AdvertisingExpense	418000
CY2019	us-gaap	Advertising Expense AdvertisingExpense	434000
CY2018	us-gaap	Advertising Expense AdvertisingExpense	373000
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1
CY2019Q4	us-gaap	Cash Reserve Deposit Required And Made CashReserveDepositRequiredAndMade	0
CY2020Q4	us-gaap	Cash Reserve Deposit Required And Made CashReserveDepositRequiredAndMade	0
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	424981000
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	10473000
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	374000
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	435080000
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	340706000
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	3131000
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	940000
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	342897000
CY2020	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	342000
CY2019	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	81000
CY2018	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	0
CY2020	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	46000
CY2019	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	84000
CY2018	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	20000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	16281000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	16447000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	78502000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	80214000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	58501000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	59251000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	21145000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	22419000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	174429000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	178331000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	250552000
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	256749000
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	424981000
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	435080000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	95948000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	374000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	0
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	95948000
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	374000
CY2020Q4	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	8
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	95948000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	374000
CY2020Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	0
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	61678000
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	238000
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	69578000
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	702000
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	131256000
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	940000
CY2020Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	41916000
CY2019Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	37943000
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	893214000
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	780645000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	15416000
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12356000
CY2020Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	-1968000
CY2019Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	584000
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	875830000
CY2019Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	768873000
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	878003000
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	15211000
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	893214000
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	779162000
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	1157000
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	780645000
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	15211000
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	1157000
CY2020Q4	fnrn	Loans And Leases Receivable Nonaccrual Status Commitment To Lend LoansAndLeasesReceivableNonaccrualStatusCommitmentToLend	0
CY2019Q4	fnrn	Loans And Leases Receivable Nonaccrual Status Commitment To Lend LoansAndLeasesReceivableNonaccrualStatusCommitmentToLend	0
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	17925000
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	10246000
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	7225000
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	17471000
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2347000
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	4625000
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	1157000
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	3318000
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	4475000
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	273000
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	12677000
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	199000
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	7008000
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	688000
CY2018	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	8518000
CY2018	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	323000
CY2018	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	0
CY2019	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	0
CY2020	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	0
CY2020	fnrn	Period Of Continuous Payment For Reclassification Of Nonaccrual Loans To Accruing Status PeriodOfContinuousPaymentForReclassificationOfNonaccrualLoansToAccruingStatus	P6M
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	2325000
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	3413000
CY2020Q4	fnrn	Financing Receivable Specific Reserves For Modified Recorded Investment FinancingReceivableSpecificReservesForModifiedRecordedInvestment	253000
CY2019Q4	fnrn	Financing Receivable Specific Reserves For Modified Recorded Investment FinancingReceivableSpecificReservesForModifiedRecordedInvestment	273000
CY2020Q4	fnrn	Financing Receivable Modifications Loans In Compliance FinancingReceivableModificationsLoansInCompliance	2260000
CY2019Q4	fnrn	Financing Receivable Modifications Loans In Compliance FinancingReceivableModificationsLoansInCompliance	3318000
CY2020Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	0
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	0
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	2
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	189000
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	189000
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	1
CY2018	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	191000
CY2018	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	191000
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12822000
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	17471000
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	875743000
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	893214000
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	2347000
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	13069000
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	4475000
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	776170000
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	780645000
CY2018Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	10874000
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	893214000
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	780645000
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12356000
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3050000
CY2020	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	227000
CY2020	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	237000
CY2020	us-gaap	Allowance For Loan And Lease Losses Writeoffs Net AllowanceForLoanAndLeaseLossesWriteoffsNet	-10000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	15416000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	15416000
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12822000
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0
CY2019	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	779000
CY2019	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	313000
CY2019	us-gaap	Allowance For Loan And Lease Losses Writeoffs Net AllowanceForLoanAndLeaseLossesWriteoffsNet	466000
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12356000
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	273000
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	12083000
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12356000
CY2017Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	11133000
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2100000
CY2018	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	685000
CY2018	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	274000
CY2018	us-gaap	Allowance For Loan And Lease Losses Writeoffs Net AllowanceForLoanAndLeaseLossesWriteoffsNet	411000
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12822000
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	855000
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	11967000
CY2018Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	764620000
CY2018Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	775494000
CY2020Q4	fnrn	Mortgage Loans On Real Estate Serviced For Others MortgageLoansOnRealEstateServicedForOthers	206208000
CY2019Q4	fnrn	Mortgage Loans On Real Estate Serviced For Others MortgageLoansOnRealEstateServicedForOthers	208862000
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1481000
CY2020	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	575000
CY2020	us-gaap	Servicing Asset At Amortized Value Disposals ServicingAssetAtAmortizedValueDisposals	428000
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1628000
CY2019Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2020	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisions	386000
CY2020	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRecoveries	0
CY2020Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	386000
CY2019Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Beginning Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceBeginningBalance	1481000
CY2020	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Additions ServicingAssetAtAmortizedCostNetOfValuationAllowanceAdditions	189000
CY2020	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Reductions ServicingAssetAtAmortizedCostNetOfValuationAllowanceReductions	428000
CY2020Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Ending Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceEndingBalance	1242000
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1579000
CY2019	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	198000
CY2019	us-gaap	Servicing Asset At Amortized Value Disposals ServicingAssetAtAmortizedValueDisposals	296000
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1481000
CY2018Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2019	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisions	0
CY2019	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRecoveries	0
CY2019Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2018Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Beginning Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceBeginningBalance	1579000
CY2019	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Additions ServicingAssetAtAmortizedCostNetOfValuationAllowanceAdditions	198000
CY2019	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Reductions ServicingAssetAtAmortizedCostNetOfValuationAllowanceReductions	296000
CY2019Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Ending Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceEndingBalance	1481000
CY2017Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1712000
CY2018	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	141000
CY2018	us-gaap	Servicing Asset At Amortized Value Disposals ServicingAssetAtAmortizedValueDisposals	274000
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1579000
CY2017Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2018	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisions	0
CY2018	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRecoveries	0
CY2018Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2017Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Beginning Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceBeginningBalance	1712000
CY2018	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Additions ServicingAssetAtAmortizedCostNetOfValuationAllowanceAdditions	141000
CY2018	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Reductions ServicingAssetAtAmortizedCostNetOfValuationAllowanceReductions	274000
CY2018Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Ending Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceEndingBalance	1579000
CY2020Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	1242000
CY2019Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	1631000
CY2020	us-gaap	Contractually Specified Servicing Fees Amount ContractuallySpecifiedServicingFeesAmount	528000
CY2019	us-gaap	Contractually Specified Servicing Fees Amount ContractuallySpecifiedServicingFeesAmount	523000
CY2018	us-gaap	Contractually Specified Servicing Fees Amount ContractuallySpecifiedServicingFeesAmount	549000
CY2020Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	17185000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	7054000
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	23222000
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	22362000
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	16709000
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	15768000
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6513000
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6594000
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	943000
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	721000
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	565000
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	5099000
CY2019Q4	us-gaap	Interest Receivable InterestReceivable	4295000
CY2020Q4	us-gaap	Servicing Asset ServicingAsset	1242000
CY2019Q4	us-gaap	Servicing Asset ServicingAsset	1481000
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	0
CY2020	fnrn	Lessee Operating Lease Number Of Branch And Administrative Locations LesseeOperatingLeaseNumberOfBranchAndAdministrativeLocations	10
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	5913000
CY2019Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	16725000
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	2930000
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	3481000
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	5913000
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	6962000
CY2020Q4	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	5814000
CY2019Q4	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	4386000
CY2020Q4	us-gaap	Interest Receivable And Other Assets InterestReceivableAndOtherAssets	38183000
CY2019Q4	us-gaap	Interest Receivable And Other Assets InterestReceivableAndOtherAssets	37330000
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	0
CY2020Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	0
CY2019Q4	us-gaap	Federal Funds Purchased FederalFundsPurchased	0
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	0
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	6962000
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	6453000
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	7483000
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	1275000
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	1049000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	1174000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	1083000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	948000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	840000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	817000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	2192000
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	601000
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	6453000
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	1148000
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	882000
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	221000
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7827000
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y2M23D
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CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	13567587
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.90
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.08
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CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	3654000
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CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	5220000
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CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-22000
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-499000
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1429000
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	450000
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1210000
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4501000
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	5670000
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4744000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	4838000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	3901000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	101000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	108000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	1456000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	1378000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	256000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	181000
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	871000
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	576000
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CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.271
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CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0
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CY2020	us-gaap	Interest Paid Net InterestPaidNet	1517000
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CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	2273000
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	2188000
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CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	5635000
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	5428000
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-870000
CY2020	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	0
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CY2018	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0

Files In Submission

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$FNRN
FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn

2020 Q4 Form 10-K Financial Statement

#000114036121007530 Filed on March 08, 2021

Income Statement

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Facts In Submission

Files In Submission

$FNRN FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn

2020 Q4 Form 10-K Financial Statement

#000114036121007530 Filed on March 08, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$FNRN
FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn