$FNRN
FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn

$fnrn Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000114036124012415 Filed on March 11, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$18.54M		$74.12M
YoY Change	9.65%		32.64%
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	$268.0K	$498.0K	$1.002M
YoY Change	16.52%	145.32%	29.46%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$3.181M		$7.584M
YoY Change	242.04%		539.46%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$5.942M	$9.488M	$29.65M
YoY Change	-21.51%	44.5%	36.83%
Income Tax	$1.666M	$2.606M	$8.092M
% Of Pretax Income	28.04%	27.47%	27.3%
Net Earnings	$4.276M	$6.882M	$21.55M
YoY Change	-22.1%	45.53%	35.7%
Net Earnings / Revenue	23.06%		29.08%
Basic Earnings Per Share	$0.28		$1.42
Diluted Earnings Per Share	$0.28	$0.37	$1.41
COMMON SHARES
Basic Shares Outstanding	14.83M	14.73M	15.19M
Diluted Shares Outstanding	15.39M		15.33M

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$186.9M	$149.2M
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	$9.694M	$9.962M	$14.04M
YoY Change	-1.06%	62.72%	27.28%
Goodwill		$0.00
YoY Change
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets			$19.59M
YoY Change			-18.95%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$1.887B	$1.872B	$1.872B
YoY Change	-0.85%	0.03%	0.03%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$11.59M	$15.56M	$15.56M
YoY Change	4.95%	10.93%	10.93%
Accrued Expenses	$4.313M	$4.585M	$4.585M
YoY Change	-19.95%	-15.44%	-15.44%
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$15.90M	$20.14M	$20.14M
YoY Change	-3.21%	3.58%	3.58%
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	$15.90M	$20.14M	$20.14M
Total Long-Term Liabilities	$0.00	$0.00	$0.00
Total Liabilities	$1.725B	$1.713B	$1.713B
YoY Change	-2.42%	-1.93%	-1.93%
SHAREHOLDERS EQUITY
Retained Earnings	$72.70M	$68.76M
YoY Change	23.73%	26.18%
Common Stock	$124.8M	$124.2M
YoY Change	6.21%	6.1%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$162.3M	$159.2M	$159.2M
YoY Change
Total Liabilities & Shareholders Equity	$1.887B	$1.872B	$1.872B
YoY Change	-0.85%	0.03%	0.03%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$4.276M	$6.882M	$21.55M
YoY Change	-22.1%	45.53%	35.7%
Depreciation, Depletion And Amortization	$268.0K	$498.0K	$1.002M
YoY Change	16.52%	145.32%	29.46%
Cash From Operating Activities	$2.651M	$2.301M	$27.30M
YoY Change	-47.36%	-73.72%	25.34%
INVESTING ACTIVITIES
Capital Expenditures	$0.00	$176.0K	$1.221M
YoY Change	-100.0%	-42.67%	254.94%
Acquisitions
YoY Change
Other Investing Activities	$18.63M	$3.785M	$84.83M
YoY Change	-82.16%	-129.72%	-147.54%
Cash From Investing Activities	$18.63M	$3.609M	$83.61M
YoY Change	-82.11%	-127.67%	-146.76%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$47.00K
YoY Change			-33.8%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	16.42M	-53.80M	-149.1M
YoY Change	-118.15%	-25.99%	9794.76%
NET CHANGE
Cash From Operating Activities	2.651M	2.301M	27.30M
Cash From Investing Activities	18.63M	3.609M	83.61M
Cash From Financing Activities	16.42M	-53.80M	-149.1M
Net Change In Cash	37.70M	-47.89M	-38.21M
YoY Change	101.67%	-37.79%	-75.9%
FREE CASH FLOW
Cash From Operating Activities	$2.651M	$2.301M	$27.30M
Capital Expenditures	$0.00	$176.0K	$1.221M
Free Cash Flow	$2.651M	$2.125M	$26.08M
YoY Change	-44.2%	-74.85%	21.66%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value
CY2023Q4	us-gaap	Certificates Of Deposit At Carrying Value CertificatesOfDepositAtCarryingValue	19710000
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	572357000
CY2022Q4	fnrn	Time Deposits Over250000 TimeDepositsOver250000	9240000
CY2023Q4	us-gaap	Deposits Deposits	1692444000
CY2022Q4	us-gaap	Deposits Deposits	1726874000
CY2023Q4	us-gaap	Notes Receivable Net NotesReceivableNet	1052465000
CY2022	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansTax	-28000
CY2023	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-68000
CY2022	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-66000
CY2023	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	5368000
CY2022	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-17833000
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	12801000
CY2023	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	111000
CY2022	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	145000
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-404000
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-687000
CY2023	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	0
CY2022	us-gaap	Servicing Asset At Amortized Value Valuation Allowance ServicingAssetAtAmortizedValueValuationAllowance	-276000
CY2023	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	5918000
CY2022	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	10693000
CY2023	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	5807000
CY2022	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	9485000
CY2022Q4	us-gaap	Certificates Of Deposit At Carrying Value CertificatesOfDepositAtCarryingValue	20948000
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	618092000
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	16596000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	14792000
CY2022Q4	us-gaap	Notes Receivable Net NotesReceivableNet	970138000
CY2022Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	9440000
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	9962000
CY2023Q4	us-gaap	Interest Receivable And Other Assets InterestReceivableAndOtherAssets	53468000
CY2022Q4	us-gaap	Interest Receivable And Other Assets InterestReceivableAndOtherAssets	59204000
CY2023Q4	us-gaap	Assets Assets	1871832000
CY2022Q4	us-gaap	Assets Assets	1871361000
CY2023Q4	us-gaap	Demand Deposit Accounts DemandDepositAccounts	744799000
CY2022Q4	us-gaap	Demand Deposit Accounts DemandDepositAccounts	775173000
CY2023Q4	us-gaap	Interest Bearing Deposit Liabilities InterestBearingDepositLiabilities	380477000
CY2022Q4	us-gaap	Interest Bearing Deposit Liabilities InterestBearingDepositLiabilities	448039000
CY2023Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	431472000
CY2022Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	459307000
CY2023Q4	fnrn	Time Deposits250000 Or Less TimeDeposits250000OrLess	109373000
CY2022Q4	fnrn	Time Deposits250000 Or Less TimeDeposits250000OrLess	35115000
CY2023Q4	fnrn	Time Deposits Over250000 TimeDepositsOver250000	26323000
CY2023Q4	fnrn	Interest Payable And Other Liabilities InterestPayableAndOtherLiabilities	20143000
CY2022Q4	fnrn	Interest Payable And Other Liabilities InterestPayableAndOtherLiabilities	19447000
CY2023Q4	us-gaap	Liabilities Liabilities	1712587000
CY2022Q4	us-gaap	Liabilities Liabilities	1746321000
CY2023Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
CY2022Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
CY2023Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2022Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	32000000
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	32000000
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	15482332
CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	15482332
CY2022Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	14652584
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	14652584
CY2023Q4	us-gaap	Common Stock Value CommonStockValue	123235000
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	116099000
CY2023Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	977000
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	68760000
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	54492000
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-33727000
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-46528000
CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	1871832000
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	1871361000
CY2023	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	52203000
CY2022	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	42316000
CY2023	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	9351000
CY2022	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	3829000
CY2023	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	10850000
CY2023	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	914000
CY2022	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	909000
CY2023	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	805000
CY2022	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	532000
CY2023	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	74123000
CY2022	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	55882000
CY2023	fnrn	Interest Expense Time Deposits Over250000 InterestExpenseTimeDepositsOver250000	410000
CY2022	fnrn	Interest Expense Time Deposits Over250000 InterestExpenseTimeDepositsOver250000	35000
CY2023	us-gaap	Interest Expense Other Domestic Deposits InterestExpenseOtherDomesticDeposits	7174000
CY2023	us-gaap	Interest Expense InterestExpense	7584000
CY2022	us-gaap	Interest Expense InterestExpense	1186000
CY2023	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	66539000
CY2022	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	54696000
CY2023	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	65439000
CY2022	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	53796000
CY2023	fnrn	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	1699000
CY2022	fnrn	Service Charges On Deposit Accounts ServiceChargesOnDepositAccounts	1672000
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-112000
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-152000
CY2023	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	111000
CY2022	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	145000
CY2023	fnrn	Debit Cards Income DebitCardsIncome	2798000
CY2022	fnrn	Debit Cards Income DebitCardsIncome	2547000
CY2023	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1944000
CY2022	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	2721000
CY2023	us-gaap	Noninterest Income NoninterestIncome	7845000
CY2022	us-gaap	Noninterest Income NoninterestIncome	6933000
CY2023	us-gaap	Labor And Related Expense LaborAndRelatedExpense	25914000
CY2022	us-gaap	Labor And Related Expense LaborAndRelatedExpense	24204000
CY2023	us-gaap	Occupancy Net OccupancyNet	4329000
CY2022	us-gaap	Occupancy Net OccupancyNet	3598000
CY2023	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	4043000
CY2022	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	3450000
CY2023	us-gaap	Supplies Expense SuppliesExpense	349000
CY2022	us-gaap	Supplies Expense SuppliesExpense	292000
CY2023	us-gaap	Advertising Expense AdvertisingExpense	474000
CY2022	us-gaap	Advertising Expense AdvertisingExpense	496000
CY2023	us-gaap	Noninterest Expense Directors Fees NoninterestExpenseDirectorsFees	327000
CY2022	us-gaap	Noninterest Expense Directors Fees NoninterestExpenseDirectorsFees	290000
CY2023	us-gaap	Other Noninterest Expense OtherNoninterestExpense	7373000
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	6733000
CY2023	us-gaap	Noninterest Expense NoninterestExpense	43638000
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	29646000
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	21666000
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8092000
CY2022	us-gaap	Net Income Loss NetIncomeLoss	15884000
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.42
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.05
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.41
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.04
CY2023	us-gaap	Net Income Loss NetIncomeLoss	21554000
CY2022	us-gaap	Net Income Loss NetIncomeLoss	15884000
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CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-43617000
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CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-44000
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-80000
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CY2023	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-100000
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-443000
CY2023	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-238000
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1112000
CY2023	fnrn	Other Comprehensive Income Loss Directors Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossDirectorsPensionAndOtherPostretirementBenefitPlansTax	-28000
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-42331000
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	34355000
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CY2022	us-gaap	Net Income Loss NetIncomeLoss	15884000
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CY2022	fnrn	Dividends Common Stock Adjustments DividendsCommonStockAdjustments	0
CY2022	fnrn	Common Stock Dividend CommonStockDividend	0
CY2022	fnrn	Cash Paid In Lieu Of Fractional Shares CashPaidInLieuOfFractionalShares	8000
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CY2023	us-gaap	Net Income Loss NetIncomeLoss	21554000
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CY2023	fnrn	Dividends Common Stock Adjustments DividendsCommonStockAdjustments	0
CY2023	fnrn	Common Stock Dividend CommonStockDividend	0
CY2023	fnrn	Cash Paid In Lieu Of Fractional Shares CashPaidInLieuOfFractionalShares	7000
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CY2023	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	0
CY2023	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	143000
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	159245000
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CY2022	us-gaap	Net Income Loss NetIncomeLoss	15884000
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	820000
CY2023	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	752000
CY2022	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	-2062000
CY2023	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	1077000
CY2022	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	1102000
CY2023	fnrn	Increase Decrease In Accrued Interest Receivable And Other Assets IncreaseDecreaseInAccruedInterestReceivableAndOtherAssets	961000
CY2022	fnrn	Increase Decrease In Accrued Interest Receivable And Other Assets IncreaseDecreaseInAccruedInterestReceivableAndOtherAssets	981000
CY2023	fnrn	Increase Decrease In Interest Payable And Other Liabilities IncreaseDecreaseInInterestPayableAndOtherLiabilities	883000
CY2022	fnrn	Increase Decrease In Interest Payable And Other Liabilities IncreaseDecreaseInInterestPayableAndOtherLiabilities	937000
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	27300000
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	21780000
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	62765000
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	22100000
CY2023	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	18067000
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	6348000
CY2023	fnrn	Proceeds From Principal Repayments Of Available For Sale Securities ProceedsFromPrincipalRepaymentsOfAvailableForSaleSecurities	71909000
CY2022	fnrn	Proceeds From Principal Repayments Of Available For Sale Securities ProceedsFromPrincipalRepaymentsOfAvailableForSaleSecurities	96308000
CY2022	fnrn	Proceeds From Maturities Of Certificates Of Deposit ProceedsFromMaturitiesOfCertificatesOfDeposit	5151000
CY2023	fnrn	Proceeds From Sales Of Certificates Of Deposit ProceedsFromSalesOfCertificatesOfDeposit	0
CY2022	fnrn	Proceeds From Sales Of Certificates Of Deposit ProceedsFromSalesOfCertificatesOfDeposit	493000
CY2023	fnrn	Proceeds From Payments For Federal Home Loan Bank Stock And Other Equity Securities ProceedsFromPaymentsForFederalHomeLoanBankStockAndOtherEquitySecurities	-1078000
CY2022	fnrn	Proceeds From Payments For Federal Home Loan Bank Stock And Other Equity Securities ProceedsFromPaymentsForFederalHomeLoanBankStockAndOtherEquitySecurities	-2343000
CY2023	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	80173000
CY2022	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	116259000
CY2023	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1221000
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	344000
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-178785000
CY2023	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-149060000
CY2022	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-1428000
CY2023	fnrn	Cash Dividends Paid In Lieu Of Fractional Shares CashDividendsPaidInLieuOfFractionalShares	7000
CY2022	fnrn	Cash Dividends Paid In Lieu Of Fractional Shares CashDividendsPaidInLieuOfFractionalShares	8000
CY2023	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	96000
CY2022	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	116000
CY2023	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	143000
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	187000
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-149114000
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1507000
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-38206000
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-158512000
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	187417000
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	345929000
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	149211000
CY2023	dei	Amendment Flag AmendmentFlag	false
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0001114927
CY2022Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#InterestReceivableAndOtherAssets
CY2023Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#InterestReceivableAndOtherAssets
CY2023Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List FinancingReceivableAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#InterestReceivableAndOtherAssets
CY2022Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List FinancingReceivableAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#InterestReceivableAndOtherAssets
CY2023	us-gaap	Contractually Specified Servicing Fee Income Statement Of Income Or Comprehensive Income Extensible Enumeration ContractuallySpecifiedServicingFeeIncomeStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#NoninterestIncomeOtherOperatingIncome
CY2022	us-gaap	Contractually Specified Servicing Fee Income Statement Of Income Or Comprehensive Income Extensible Enumeration ContractuallySpecifiedServicingFeeIncomeStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#NoninterestIncomeOtherOperatingIncome
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#InterestReceivableAndOtherAssets
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#InterestReceivableAndOtherAssets
CY2022Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://thatsmybank.com/20231231#InterestPayableAndOtherLiabilities
CY2023Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://thatsmybank.com/20231231#InterestPayableAndOtherLiabilities
CY2023	dei	Auditor Firm AuditorFirmId	659
CY2023	dei	Document Type DocumentType	10-K
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Document Period End Date DocumentPeriodEndDate	2023-12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	000-30707
CY2023	dei	Entity Registrant Name EntityRegistrantName	First Northern Community Bancorp
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	CA
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	68-0450397
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	195 N. First St.
CY2023	dei	Entity Address City Or Town EntityAddressCityOrTown	Dixon
CY2023	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
CY2023	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	95620
CY2023	dei	City Area Code CityAreaCode	707
CY2023	dei	Local Phone Number LocalPhoneNumber	678-3041
CY2023	dei	Security12g Title Security12gTitle	Common Stock, no par value
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2023	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2023	dei	Entity Filer Category EntityFilerCategory	Non-accelerated Filer
CY2023	dei	Entity Small Business EntitySmallBusiness	true
CY2023	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	false
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
CY2023Q2	dei	Entity Public Float EntityPublicFloat	92326010
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	14827366
CY2023	dei	Auditor Name AuditorName	MOSS ADAMS LLP
CY2023	dei	Auditor Location AuditorLocation	Sacramento, California
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	149211000
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	187417000
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0
CY2022Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	620314000
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	683784000
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	10518000
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6122000
CY2023Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	4141000
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	0
CY2022Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	977000
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	159245000
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	125040000
CY2022	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	8296000
CY2022	us-gaap	Interest Expense Other Domestic Deposits InterestExpenseOtherDomesticDeposits	1151000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Provision And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossProvisionAndReserveForUnfundedCommitments	1100000
CY2022	fnrn	Financing Receivable Allowance For Credit Loss Provision And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossProvisionAndReserveForUnfundedCommitments	900000
CY2023	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	1405000
CY2022	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	0
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	829000
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	0
CY2022	us-gaap	Noninterest Expense NoninterestExpense	39063000
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	5782000
CY2023	us-gaap	Net Income Loss NetIncomeLoss	21554000
CY2023	fnrn	Stock Issued During Period Value Restricted Stock Award And Employee Stock Purchase Plan Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardAndEmployeeStockPurchasePlanNetOfForfeitures	96000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Provision And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossProvisionAndReserveForUnfundedCommitments	1100000
CY2022	fnrn	Financing Receivable Allowance For Credit Loss Provision And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossProvisionAndReserveForUnfundedCommitments	900000
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	829000
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	0
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	655000
CY2023	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	1002000
CY2022	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	774000
CY2023	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1941000
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-4319000
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-112000
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-152000
CY2023	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	1405000
CY2022	us-gaap	Business Combination Bargain Purchase Gain Recognized Amount BusinessCombinationBargainPurchaseGainRecognizedAmount	0
CY2023	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	91324000
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	176919000
CY2023	fnrn	Proceeds From Maturities Of Certificates Of Deposit ProceedsFromMaturitiesOfCertificatesOfDeposit	5169000
CY2023	fnrn	Payments To Acquire Certificates Of Deposits PaymentsToAcquireCertificatesOfDeposits	3931000
CY2022	fnrn	Payments To Acquire Certificates Of Deposits PaymentsToAcquireCertificatesOfDeposits	13320000
CY2023	us-gaap	Cash Acquired From Acquisition CashAcquiredFromAcquisition	103425000
CY2022	us-gaap	Cash Acquired From Acquisition CashAcquiredFromAcquisition	0
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	83608000
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	187417000
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	984100000
CY2022Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	8176000
CY2023	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	1626000
CY2023Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	2096000
CY2022Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	2151000
CY2023	fnrn	Contractually Past Due Period After Which Accrual Of Interest On Loans Is Discontinued ContractuallyPastDuePeriodAfterWhichAccrualOfInterestOnLoansIsDiscontinued	P90D
CY2023Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	4713000
CY2022Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	3594000
CY2023Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	0
CY2022Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	0
CY2023	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.0609
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.0755
CY2023	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.105
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.095
CY2023	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P7Y11M26D
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P7Y2M12D
CY2022	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	51000
CY2023	us-gaap	Advertising Expense AdvertisingExpense	474000
CY2022	us-gaap	Advertising Expense AdvertisingExpense	496000
CY2023Q4	us-gaap	Goodwill Goodwill	0
CY2022Q4	us-gaap	Cash Reserve Deposit Required And Made CashReserveDepositRequiredAndMade	0
CY2023Q4	us-gaap	Cash Reserve Deposit Required And Made CashReserveDepositRequiredAndMade	0
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	620314000
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	733000
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	48690000
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	572357000
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	683784000
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	102000
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	65794000
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	618092000
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	96000
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	0
CY2023	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	208000
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	152000
CY2023Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1068983000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	78883000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	77408000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	131352000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	124600000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	29523000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	27427000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	26631000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	24503000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	266389000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	253938000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	353925000
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	318419000
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	620314000
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	572357000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	32025000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	188000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	470459000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	48502000
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	502484000
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	48690000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	31
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	32025000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	188000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	454
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	470459000
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	48502000
CY2023Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	275604000
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	14760000
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	327817000
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	51034000
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	603421000
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	65794000
CY2023Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	3998000
CY2022Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	8176000
CY2023Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1068983000
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	984100000
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	16596000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	14792000
CY2023Q4	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	78000
CY2022Q4	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	830000
CY2023Q4	us-gaap	Notes Receivable Net NotesReceivableNet	1052465000
CY2022Q4	us-gaap	Notes Receivable Net NotesReceivableNet	970138000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	14792000
CY2023	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	2949000
CY2023	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	2803000
CY2023	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	1150000
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	16596000
CY2022Q4	fnrn	Financing Receivable Allowance For Credit Loss And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossAndReserveForUnfundedCommitments	15492000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Charge Off And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossChargeOffAndReserveForUnfundedCommitments	-2949000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Recoveries And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossRecoveriesAndReserveForUnfundedCommitments	2803000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Provision And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossProvisionAndReserveForUnfundedCommitments	1100000
CY2023Q4	fnrn	Financing Receivable Allowance For Credit Loss And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossAndReserveForUnfundedCommitments	17746000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Provision And Reserve For Unfunded Commitments FinancingReceivableAllowanceForCreditLossProvisionAndReserveForUnfundedCommitments	1100000
CY2022	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	900000
CY2022	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	345000
CY2022	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	285000
CY2022	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	60000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	14792000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	77000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	14715000
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	14792000
CY2022Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	8739000
CY2022Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	975361000
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	984100000
CY2023Q4	fnrn	Collateral Dependent Loans Amortized Cost CollateralDependentLoansAmortizedCost	3998000
CY2022Q4	fnrn	Collateral Dependent Loans Amortized Cost CollateralDependentLoansAmortizedCost	8176000
CY2023Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	3998000
CY2022Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	11527000
CY2022Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	8176000
CY2022Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	563000
CY2022Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	8739000
CY2022Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	77000
CY2022	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	9895000
CY2022	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	75000
CY2022	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	0
CY2023	us-gaap	Financing Receivable Modification To Total Financing Receivables Percent FinancingReceivableModificationToTotalFinancingReceivablesPercent	0.0092
CY2023Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	0
CY2023	us-gaap	Financing Receivable Modified Weighted Average Interest Rate Decrease From Modification FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification	0.0027
CY2023	us-gaap	Financing Receivable Modified Weighted Average Term Increase From Modification FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification	P3M
CY2022Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	8399000
CY2022Q4	fnrn	Financing Receivable Specific Reserves For Modified Recorded Investment FinancingReceivableSpecificReservesForModifiedRecordedInvestment	77000
CY2022Q4	fnrn	Financing Receivable Modifications Loans In Compliance FinancingReceivableModificationsLoansInCompliance	8399000
CY2022	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	1
CY2022	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	75000
CY2022	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	75000
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0
CY2023Q4	us-gaap	Financing Receivable Revolving Converted To Term Loan FinancingReceivableRevolvingConvertedToTermLoan	881000
CY2023Q4	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	167123000
CY2023Q4	us-gaap	Financing Receivable Originated In Fiscal Year Before Latest Fiscal Year FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear	242030000
CY2023Q4	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	274834000
CY2023Q4	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	81433000
CY2023Q4	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	79344000
CY2023Q4	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	145005000
CY2023Q4	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	79214000
CY2023Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	1068983000
CY2023	us-gaap	Financing Receivable Year One Originated Current Fiscal Year Writeoff FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff	1885000
CY2023	us-gaap	Financing Receivable Year Two Originated Fiscal Year Before Current Fiscal Year Writeoff FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff	196000
CY2023	us-gaap	Financing Receivable Year Three Originated Two Years Before Current Fiscal Year Writeoff FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff	36000
CY2023	us-gaap	Financing Receivable Year Four Originated Three Years Before Current Fiscal Year Writeoff FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff	0
CY2023	us-gaap	Financing Receivable Year Five Originated Four Years Before Current Fiscal Year Writeoff FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff	87000
CY2023	us-gaap	Financing Receivable Originated More Than Five Years Before Current Fiscal Year Writeoff FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff	3000
CY2023	us-gaap	Financing Receivable Revolving Writeoff FinancingReceivableRevolvingWriteoff	742000
CY2023	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	2949000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Year One Originated Current Fiscal Year Year To Date Recoveries FinancingReceivableAllowanceForCreditLossYearOneOriginatedCurrentFiscalYearYearToDateRecoveries	1825000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Year Two Originated Fiscal Year Before Current Fiscal Year Year To Date Recoveries FinancingReceivableAllowanceForCreditLossYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearYearToDateRecoveries	0
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Year Three Originated Two Years Before Current Fiscal Year Year To Date Recoveries FinancingReceivableAllowanceForCreditLossYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearYearToDateRecoveries	0
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Year Four Originated Three Years Before Current Fiscal Year Year To Date Recoveries FinancingReceivableAllowanceForCreditLossYearFourOriginatedThreeYearsBeforeCurrentFiscalYearYearToDateRecoveries	0
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Year Five Originated Four Years Before Current Fiscal Year Year To Date Recoveries FinancingReceivableAllowanceForCreditLossYearFiveOriginatedFourYearsBeforeCurrentFiscalYearYearToDateRecoveries	87000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Originated More Than Five Years Before Current Fiscal Year Year To Date Recoveries FinancingReceivableAllowanceForCreditLossOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearYearToDateRecoveries	149000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Revolving Recovery FinancingReceivableAllowanceForCreditLossRevolvingRecovery	742000
CY2023	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	2803000
CY2023	fnrn	Financing Receivable Year One Originated Current Fiscal Year Net Write Offs FinancingReceivableYearOneOriginatedCurrentFiscalYearNetWriteOffs	60000
CY2023	fnrn	Financing Receivable Year Two Originated Fiscal Year Before Current Fiscal Year Net Write Offs FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearNetWriteOffs	196000
CY2023	fnrn	Financing Receivable Year Three Originated Two Years Before Current Fiscal Year Net Write Offs FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearNetWriteOffs	36000
CY2023	fnrn	Financing Receivable Year Four Originated Three Years Before Current Fiscal Year Net Write Offs FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearNetWriteOffs	0
CY2023	fnrn	Financing Receivable Year Five Originated Four Years Before Current Fiscal Year Net Write Offs FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearNetWriteOffs	0
CY2023	fnrn	Financing Receivable Originated More Than Five Years Before Current Fiscal Year Net Write Offs FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearNetWriteOffs	-146000
CY2023	fnrn	Financing Receivable Allowance For Credit Loss Revolving Write Off After Recovery FinancingReceivableAllowanceForCreditLossRevolvingWriteOffAfterRecovery	0
CY2023	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	146000
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	984100000
CY2023Q4	fnrn	Mortgage Loans On Real Estate Serviced For Others MortgageLoansOnRealEstateServicedForOthers	184288000
CY2022Q4	fnrn	Mortgage Loans On Real Estate Serviced For Others MortgageLoansOnRealEstateServicedForOthers	194818000
CY2022Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1650000
CY2023	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	67000
CY2023	us-gaap	Servicing Asset At Amortized Value Disposals ServicingAssetAtAmortizedValueDisposals	235000
CY2023Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1482000
CY2022Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2023	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisions	0
CY2023	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRecoveries	0
CY2023Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2022Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Beginning Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceBeginningBalance	1650000
CY2023	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Additions ServicingAssetAtAmortizedCostNetOfValuationAllowanceAdditions	67000
CY2023	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Reductions ServicingAssetAtAmortizedCostNetOfValuationAllowanceReductions	235000
CY2023Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Ending Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceEndingBalance	1482000
CY2021Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1807000
CY2022	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	129000
CY2022	us-gaap	Servicing Asset At Amortized Value Disposals ServicingAssetAtAmortizedValueDisposals	286000
CY2022Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	1650000
CY2021Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	276000
CY2022	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Provisions ValuationAllowanceForImpairmentOfRecognizedServicingAssetsProvisions	0
CY2022	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Recoveries ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRecoveries	276000
CY2022Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0
CY2021Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Beginning Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceBeginningBalance	1531000
CY2022	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Additions ServicingAssetAtAmortizedCostNetOfValuationAllowanceAdditions	129000
CY2022	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Reductions ServicingAssetAtAmortizedCostNetOfValuationAllowanceReductions	10000
CY2022Q4	fnrn	Servicing Asset At Amortized Cost Net Of Valuation Allowance Balance Ending Balance ServicingAssetAtAmortizedCostNetOfValuationAllowanceBalanceEndingBalance	1650000
CY2023Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	2094000
CY2022Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	2101000
CY2023	us-gaap	Contractually Specified Servicing Fees Amount ContractuallySpecifiedServicingFeesAmount	473000
CY2022	us-gaap	Contractually Specified Servicing Fees Amount ContractuallySpecifiedServicingFeesAmount	509000
CY2023Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	29135000
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	24370000
CY2023Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	19173000
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	18248000
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	9962000
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6122000
CY2023	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	1002000
CY2022	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	774000
CY2023Q4	us-gaap	Interest Receivable InterestReceivable	6810000
CY2022Q4	us-gaap	Interest Receivable InterestReceivable	5745000
CY2023Q4	us-gaap	Servicing Asset ServicingAsset	1482000
CY2022Q4	us-gaap	Servicing Asset ServicingAsset	1650000
CY2023Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	15638000
CY2022Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	15599000
CY2023Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	19594000
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	24175000
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	4073000
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	4905000
CY2023Q4	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	5871000
CY2022Q4	us-gaap	Prepaid Expense And Other Assets PrepaidExpenseAndOtherAssets	7130000
CY2023Q4	us-gaap	Interest Receivable And Other Assets InterestReceivableAndOtherAssets	53468000
CY2022Q4	us-gaap	Interest Receivable And Other Assets InterestReceivableAndOtherAssets	59204000
CY2023	fnrn	Lessee Operating Lease Number Of Branch And Administrative Locations LesseeOperatingLeaseNumberOfBranchAndAdministrativeLocations	11
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	4073000
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	4905000
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	4585000
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	5422000
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	4917000
CY2023Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	19594000
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	1217000
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	1154000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	1040000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	1052000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	672000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	610000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	625000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	895000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	4894000
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	309000
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	4585000
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	1207000
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	1251000
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	245000
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	869000
CY2023Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y5M4D
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y1M20D
CY2023Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0242
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0237
CY2023Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	188652000
CY2022Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	207540000
	fnrn	Financing Receivable Repurchased Number FinancingReceivableRepurchasedNumber	1
	fnrn	Financing Receivable Repurchased Amount FinancingReceivableRepurchasedAmount	420000
CY2023Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	113436000
CY2023Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	18453000
CY2023Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	2057000
CY2023Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	1288000
CY2023Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	220000
CY2023Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	242000
CY2023Q4	us-gaap	Time Deposits TimeDeposits	135696000
CY2023	us-gaap	Net Income Loss NetIncomeLoss	21554000
CY2022	us-gaap	Net Income Loss NetIncomeLoss	15884000
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15185852
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15089635
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.42
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.05
CY2023	us-gaap	Net Income Loss NetIncomeLoss	21554000
CY2022	us-gaap	Net Income Loss NetIncomeLoss	15884000
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15185852
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15089635
CY2023	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	143633
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	165789
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15329485
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15255424
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.41
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.04
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	5349000
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	4141000
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	3147000
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	2328000
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	8496000
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6469000
CY2023	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-400000
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-599000
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-4000
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-88000
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-404000
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-687000
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8092000
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	5782000
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	5246000
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	4580000
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	64000
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	82000
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	1617000
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	1635000
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	453000
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	379000
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	0
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CY2023	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	1.42
CY2022	us-gaap	Business Acquisition Pro Forma Earnings Per Share Basic BusinessAcquisitionProFormaEarningsPerShareBasic	1.04
CY2023	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	1.41
CY2022	us-gaap	Business Acquisition Pro Forma Earnings Per Share Diluted BusinessAcquisitionProFormaEarningsPerShareDiluted	1.03
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CY2023Q4	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false

Files In Submission

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$FNRN
FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn

2024 Q1 Form 10-K Financial Statement

#000114036124012415 Filed on March 11, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$FNRN FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn

2024 Q1 Form 10-K Financial Statement

#000114036124012415 Filed on March 11, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$FNRN
FIRST NORTHERN COMMUNITY BANCORP Stock $fnrn