$NFBK
Northfield Bancorp, Inc. Stock $nfbk

$nfbk Overview Financials Valuation SEC Filings Company Website

2021 Q1 Form 10-Q Financial Statement

#000149322521000066 Filed on May 10, 2021

Income Statement

Concept	2021 Q1	2020 Q1
Revenue	$45.07M	$42.73M
YoY Change	5.46%	8.28%
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	$1.020M	$860.0K
YoY Change	18.6%	2.38%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$4.891M	$12.80M
YoY Change	-61.79%	5.46%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$25.62M	$6.176M
YoY Change	314.88%	-45.73%
Income Tax	$6.946M	$1.625M
% Of Pretax Income	27.11%	26.31%
Net Earnings	$18.68M	$4.551M
YoY Change	310.39%	-48.11%
Net Earnings / Revenue	41.44%	10.65%
Basic Earnings Per Share	$0.38	$0.10
Diluted Earnings Per Share	$0.38	$0.10
COMMON SHARES
Basic Shares Outstanding	49.53M shares	46.79M shares
Diluted Shares Outstanding	49.63M shares	46.98M shares

Balance Sheet

Concept	2021 Q1	2020 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$127.6M	$114.7M
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	$27.51M	$25.67M
YoY Change	7.16%	1.82%
Goodwill	$41.32M	$38.41M
YoY Change	7.57%	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$5.577B	$4.997B
YoY Change	11.61%	9.69%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$24.00M	$22.40M
YoY Change	7.14%	8.21%
Accrued Expenses	$70.40M	$70.10M
YoY Change	0.43%	-0.99%
Deferred Revenue
YoY Change
Short-Term Debt	$75.00M	$75.00M
YoY Change	0.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$94.40M	$92.50M
YoY Change	2.05%	1.09%
LONG-TERM LIABILITIES
Long-Term Debt	$517.2M	$641.4M
YoY Change	-19.36%	56.74%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$517.2M	$641.4M
YoY Change	-19.36%	56.74%
TOTAL LIABILITIES
Total Short-Term Liabilities	$94.40M	$92.50M
Total Long-Term Liabilities	$517.2M	$641.4M
Total Liabilities	$4.822B	$4.294B
YoY Change	12.29%	10.8%
SHAREHOLDERS EQUITY
Retained Earnings	$348.2M	$322.0M
YoY Change	8.15%	5.02%
Common Stock	$648.0K	$609.0K
YoY Change	6.4%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$177.5M	$159.2M
YoY Change	11.5%	5.47%
Treasury Stock Shares	13.10M shares	11.64M shares
Shareholders Equity	$754.6M	$702.3M
YoY Change
Total Liabilities & Shareholders Equity	$5.577B	$4.997B
YoY Change	11.61%	9.69%

Cashflow Statement

Concept	2021 Q1	2020 Q1
OPERATING ACTIVITIES
Net Income	$18.68M	$4.551M
YoY Change	310.39%	-48.11%
Depreciation, Depletion And Amortization	$1.020M	$860.0K
YoY Change	18.6%	2.38%
Cash From Operating Activities	$20.20M	$11.95M
YoY Change	69.04%	24.09%
INVESTING ACTIVITIES
Capital Expenditures	$293.0K	$806.0K
YoY Change	-63.65%	113.79%
Acquisitions
YoY Change
Other Investing Activities	-$29.01M	$21.65M
YoY Change	-234.0%	-124.27%
Cash From Investing Activities	-$29.30M	$20.84M
YoY Change	-240.57%	-123.26%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net	$10.13M	$0.00
YoY Change
Debt Paid & Issued, Net	$0.00	$361.0M
YoY Change	-100.0%	1344.0%
Cash From Financing Activities	$49.13M	-$65.91M
YoY Change	-174.54%	-174.87%
NET CHANGE
Cash From Operating Activities	$20.20M	$11.95M
Cash From Investing Activities	-$29.30M	$20.84M
Cash From Financing Activities	$49.13M	-$65.91M
Net Change In Cash	$40.03M	-$33.12M
YoY Change	-220.86%	-510.75%
FREE CASH FLOW
Cash From Operating Activities	$20.20M	$11.95M
Capital Expenditures	$293.0K	$806.0K
Free Cash Flow	$19.91M	$11.14M
YoY Change	78.63%	20.44%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021Q1	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021Q1	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021Q1	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q1
CY2021Q1	dei	Amendment Flag AmendmentFlag	false
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CY2021Q1	dei	Document Period End Date DocumentPeriodEndDate	2021-03-31
CY2021Q1	dei	Document Transition Report DocumentTransitionReport	false
CY2021Q1	dei	Entity File Number EntityFileNumber	001-35791
CY2021Q1	dei	Entity Registrant Name EntityRegistrantName	Northfield Bancorp, Inc.
CY2021Q1	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021Q1	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	80-0882592
CY2021Q1	dei	Entity Address Address Line1 EntityAddressAddressLine1	581 Main Street,
CY2021Q1	dei	Entity Address City Or Town EntityAddressCityOrTown	Woodbridge,
CY2021Q1	dei	Entity Address State Or Province EntityAddressStateOrProvince	NJ
CY2021Q1	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	07095
CY2021Q1	dei	City Area Code CityAreaCode	732
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CY2020Q1	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	8323000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-321000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	2326000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	27000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-3000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-893000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	5994000	USD
CY2021Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	17784000	USD
CY2020Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	10545000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	695853000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	4551000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	5994000	USD
CY2020Q1	us-gaap	Amortization Of Esop Award AmortizationOfESOPAward	446000	USD
CY2020Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	448000	USD
CY2020Q1	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2020Q1	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	175000	USD
CY2020Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.11
CY2020Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.11
CY2020Q1	us-gaap	Dividends Common Stock DividendsCommonStock	5151000	USD
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	702316000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	753981000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	18677000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-893000	USD
CY2021Q1	us-gaap	Amortization Of Esop Award AmortizationOfESOPAward	412000	USD
CY2021Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	244000	USD
CY2021Q1	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2021Q1	us-gaap	Restricted Stock Award Forfeitures RestrictedStockAwardForfeitures	0	USD
CY2021Q1	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	808000	USD
CY2021Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.11
CY2021Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.11
CY2021Q1	us-gaap	Dividends Common Stock DividendsCommonStock	5447000	USD
CY2021Q1	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	13.64
CY2021Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	10130000	USD
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	754565000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	18677000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	4551000	USD
CY2021Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-2374000	USD
CY2020Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	8183000	USD
CY2021Q1	us-gaap	Share Based Compensation ShareBasedCompensation	656000	USD
CY2020Q1	us-gaap	Share Based Compensation ShareBasedCompensation	894000	USD
CY2021Q1	us-gaap	Depreciation Nonproduction DepreciationNonproduction	972000	USD
CY2020Q1	us-gaap	Depreciation Nonproduction DepreciationNonproduction	795000	USD
CY2021Q1	nfbk	Amortization Of Premiums And Deferred Loan Costs AmortizationOfPremiumsAndDeferredLoanCosts	564000	USD
CY2020Q1	nfbk	Amortization Of Premiums And Deferred Loan Costs AmortizationOfPremiumsAndDeferredLoanCosts	1065000	USD
CY2021Q1	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	50000	USD
CY2020Q1	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	55000	USD
CY2021Q1	nfbk	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	1079000	USD
CY2020Q1	nfbk	Operating Lease Right Of Use Asset Amortization OperatingLeaseRightOfUseAssetAmortization	1059000	USD
CY2021Q1	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	848000	USD
CY2020Q1	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	876000	USD
CY2021Q1	us-gaap	Gain Loss On Sale Of Notes Receivable GainLossOnSaleOfNotesReceivable	39000	USD
CY2020Q1	us-gaap	Gain Loss On Sale Of Notes Receivable GainLossOnSaleOfNotesReceivable	0	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Gain Loss DebtSecuritiesAvailableForSaleGainLoss	97000	USD
CY2020Q1	us-gaap	Debt Securities Available For Sale Gain Loss DebtSecuritiesAvailableForSaleGainLoss	-13000	USD
CY2021Q1	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	364000	USD
CY2020Q1	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-1992000	USD
CY2021Q1	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-513000	USD
CY2020Q1	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-842000	USD
CY2021Q1	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	63000	USD
CY2020Q1	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-311000	USD
CY2021Q1	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-2905000	USD
CY2020Q1	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	1023000	USD
CY2021Q1	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-1433000	USD
CY2020Q1	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-5912000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	20198000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	11949000	USD
CY2021Q1	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	107720000	USD
CY2020Q1	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	72609000	USD
CY2021Q1	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	23537000	USD
CY2020Q1	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	0	USD
CY2021Q1	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	0	USD
CY2020Q1	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	7515000	USD
CY2021Q1	nfbk	Redemptions Of Federal Home Loan Bank Stock RedemptionsOfFederalHomeLoanBankStock	0	USD
CY2020Q1	nfbk	Redemptions Of Federal Home Loan Bank Stock RedemptionsOfFederalHomeLoanBankStock	17235000	USD
CY2021Q1	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	103743000	USD
CY2020Q1	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	26320000	USD
CY2021Q1	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	220000	USD
CY2020Q1	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	142000	USD
CY2021Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	152892000	USD
CY2020Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	110946000	USD
CY2021Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	306000	USD
CY2020Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	52000	USD
CY2021Q1	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	5942000	USD
CY2020Q1	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	USD
CY2021Q1	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
CY2020Q1	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2000	USD
CY2021Q1	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	293000	USD
CY2020Q1	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	806000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-29299000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	20843000	USD
CY2021Q1	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	59165000	USD
CY2020Q1	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	77313000	USD
CY2021Q1	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	5447000	USD
CY2020Q1	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	5151000	USD
CY2021Q1	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	808000	USD
CY2020Q1	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	175000	USD
CY2021Q1	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	10130000	USD
CY2020Q1	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2021Q1	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	4350000	USD
CY2020Q1	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	2399000	USD
CY2021Q1	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	381000	USD
CY2020Q1	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	220353000	USD
CY2021Q1	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2020Q1	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	361000000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	49127000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-65911000	USD
CY2021Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	40026000	USD
CY2020Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-33119000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	87544000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	147818000	USD
CY2021Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	127570000	USD
CY2020Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	114699000	USD
CY2021Q1	us-gaap	Interest Paid Net InterestPaidNet	5042000	USD
CY2020Q1	us-gaap	Interest Paid Net InterestPaidNet	13003000	USD
CY2021Q1	us-gaap	Income Taxes Paid IncomeTaxesPaid	496000	USD
CY2020Q1	us-gaap	Income Taxes Paid IncomeTaxesPaid	550000	USD
CY2021Q1	us-gaap	Allowance For Loan And Lease Losses Writeoffs Net AllowanceForLoanAndLeaseLossesWriteoffsNet	2389000	USD
CY2020Q1	us-gaap	Allowance For Loan And Lease Losses Writeoffs Net AllowanceForLoanAndLeaseLossesWriteoffsNet	90000	USD
CY2021Q1	us-gaap	Financing Receivable Reclassification To Held For Sale FinancingReceivableReclassificationToHeldForSale	5215000	USD
CY2020Q1	us-gaap	Financing Receivable Reclassification To Held For Sale FinancingReceivableReclassificationToHeldForSale	0	USD
CY2021Q1	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	1612000	USD
CY2020Q1	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	USD
CY2021Q1	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	100000	USD
CY2020Q1	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	0	USD
CY2021Q1	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2020Q1	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	3028000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1190347000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	17820000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	929000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1207238000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1246673000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	18862000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	730000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1264805000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	587200000	USD
CY2021Q1	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	5900000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	97000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	0	USD
CY2020Q1	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	USD
CY2020Q1	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	0	USD
CY2020Q1	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	13000	USD
CY2021Q1	us-gaap	Debt Securities Trading Realized Gain Loss DebtSecuritiesTradingRealizedGainLoss	364000	USD
CY2020Q1	us-gaap	Debt Securities Trading Realized Gain Loss DebtSecuritiesTradingRealizedGainLoss	-2000000.0	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	924000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	128847000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	5000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	254000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	929000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	129101000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	719000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	242146000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	11000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	459000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	730000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	242605000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	1500000	USD
CY2021Q1	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	6913000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	328000	USD
CY2021Q1	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	7241000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	7234000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	340000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	7574000	USD
CY2021Q1	us-gaap	Debt Securities Held To Maturity Sold Amount DebtSecuritiesHeldToMaturitySoldAmount	0	USD
CY2020Q1	us-gaap	Debt Securities Held To Maturity Sold Amount DebtSecuritiesHeldToMaturitySoldAmount	0	USD
CY2021Q1	us-gaap	Held To Maturity Securities Restricted HeldToMaturitySecuritiesRestricted	5900000	USD
CY2020Q4	nfbk	Debt Securities Held To Maturity Unrealized Loss Position Number Of Positions DebtSecuritiesHeldToMaturityUnrealizedLossPositionNumberOfPositions	0	security
CY2021Q1	nfbk	Debt Securities Held To Maturity Unrealized Loss Position Number Of Positions DebtSecuritiesHeldToMaturityUnrealizedLossPositionNumberOfPositions	0	security
CY2021Q1	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss	20800	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni And Without Readily Determinable Fair Value EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue	473000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni And Without Readily Determinable Fair Value EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue	253000	USD
CY2021Q1	nfbk	Delinquent Status Classification Criteria Days Minimum DelinquentStatusClassificationCriteriaDaysMinimum	P90D
CY2021Q1	nfbk	Delinquent Status Classification Criteria Days Minimum DelinquentStatusClassificationCriteriaDaysMinimum	P90D
CY2021Q1	us-gaap	Notes Receivable Gross NotesReceivableGross	3933015000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3823238000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	43197000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37607000	USD
CY2021Q1	us-gaap	Notes Receivable Net NotesReceivableNet	3889818000	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	3785631000	USD
CY2021Q1	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	0	USD
CY2020Q4	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	19900000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	8400000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	8500000	USD
CY2021Q1	nfbk	Principal Balance Threshold For Non Accrual Status PrincipalBalanceThresholdForNonAccrualStatus	500000	USD
CY2021Q1	nfbk	Loans Deemed To Be Impaired Non Accrual Amount LoansDeemedToBeImpairedNonAccrualAmount	5400000	USD
CY2020Q4	nfbk	Loans Deemed To Be Impaired Non Accrual Amount LoansDeemedToBeImpairedNonAccrualAmount	5500000	USD
CY2021Q1	nfbk	Principal Balance Threshold For Non Accrual Status PrincipalBalanceThresholdForNonAccrualStatus	500000	USD
CY2021Q1	nfbk	Loans On Non Accrual Status With Principal Balances Below Threshold Definition Of Impaired Loan LoansOnNonAccrualStatusWithPrincipalBalancesBelowThresholdDefinitionOfImpairedLoan	3000000.0	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	7800000	USD
CY2020Q4	nfbk	Loans On Non Accrual Status With Principal Balances Below Threshold Definition Of Impaired Loan LoansOnNonAccrualStatusWithPrincipalBalancesBelowThresholdDefinitionOfImpairedLoan	3000000.0	USD
	nfbk	Delinquent Status Classification Criteria Days Minimum DelinquentStatusClassificationCriteriaDaysMinimum	P90D
CY2021Q1	nfbk	Delinquent Status Classification Criteria Days Minimum DelinquentStatusClassificationCriteriaDaysMinimum	P90D
CY2021Q1	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	1600000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	1100000	USD
CY2021Q1	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	0	USD
CY2020Q4	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	19900000	USD
	nfbk	Delinquent Status Classification Criteria Days Minimum DelinquentStatusClassificationCriteriaDaysMinimum	P90D
CY2021Q1	nfbk	Delinquent Status Classification Criteria Days Minimum DelinquentStatusClassificationCriteriaDaysMinimum	P90D
CY2021Q1	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	8446000	USD
CY2021Q1	nfbk	Financing Receivable Nonaccrual Unpaid Principal Balance FinancingReceivableNonaccrualUnpaidPrincipalBalance	9439000	USD
CY2021Q1	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	4654000	USD
CY2021Q1	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	243000	USD
CY2021Q1	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	49000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	13242000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	15512000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	73000	USD
CY2020Q1	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	20738000	USD
CY2020Q1	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	159000	USD
CY2021Q1	nfbk	Financing Receivable Impaired Secured By Collateral FinancingReceivableImpairedSecuredByCollateral	9800000	USD
CY2020Q4	nfbk	Financing Receivable Impaired Secured By Collateral FinancingReceivableImpairedSecuredByCollateral	10000000.0	USD
CY2021Q1	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	0	loan
CY2020Q1	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	0	loan
CY2021Q1	nfbk	Trouble Debt Restructuring Amount TroubleDebtRestructuringAmount	11700000	USD
CY2020Q4	nfbk	Trouble Debt Restructuring Amount TroubleDebtRestructuringAmount	12100000	USD
CY2021Q1	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	contract
CY2020Q1	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	27000	contract
CY2021Q1	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	13200000	USD
CY2020Q1	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	448000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	43197000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	28707000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	470000	USD
CY2021Q1	nfbk	Financing Receivable Threshold Individually Evaluated For Impairment FinancingReceivableThresholdIndividuallyEvaluatedForImpairment	500000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	77000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	73000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	808000	USD
CY2021Q1	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	157000	USD
CY2021Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1702000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37607000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	2432000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	43000	USD
CY2021Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-2374000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	380000	USD
CY2020Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	8183000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	36800000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	77000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	43120000	USD
CY2021Q1	us-gaap	Notes Receivable Gross NotesReceivableGross	3933015000	USD
CY2021Q1	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	12684000	USD
CY2021Q1	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	3752457000	USD
CY2021Q1	nfbk	Financing Receivable Not Evaluated For Impairment FinancingReceivableNotEvaluatedForImpairment	167874000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	73000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	37534000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3823238000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	13242000	USD
CY2020Q4	nfbk	Financing Receivable Not Evaluated For Impairment FinancingReceivableNotEvaluatedForImpairment	126535000	USD
CY2021Q1	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	771432000	USD
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	695831000	USD
CY2021Q1	us-gaap	Deposits Negotiable Order Of Withdrawal Now DepositsNegotiableOrderOfWithdrawalNOW	918367000	USD
CY2020Q4	us-gaap	Deposits Negotiable Order Of Withdrawal Now DepositsNegotiableOrderOfWithdrawalNOW	905208000	USD
CY2021Q1	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	1815727000	USD
CY2020Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	1953885000	USD
CY2021Q1	us-gaap	Time Deposits TimeDeposits	630190000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	521627000	USD
CY2021Q1	us-gaap	Deposits Deposits	4135716000	USD
CY2020Q4	us-gaap	Deposits Deposits	4076551000	USD
CY2021Q1	us-gaap	Interest Expense Domestic Deposit Liabilities Demand InterestExpenseDomesticDepositLiabilitiesDemand	932000	USD
CY2020Q1	us-gaap	Interest Expense Domestic Deposit Liabilities Demand InterestExpenseDomesticDepositLiabilitiesDemand	4073000	USD
CY2021Q1	us-gaap	Interest Expense Domestic Deposit Liabilities Certificates Of Deposit InterestExpenseDomesticDepositLiabilitiesCertificatesOfDeposit	938000	USD
CY2020Q1	us-gaap	Interest Expense Domestic Deposit Liabilities Certificates Of Deposit InterestExpenseDomesticDepositLiabilitiesCertificatesOfDeposit	5206000	USD
CY2021Q1	us-gaap	Interest Expense Deposits InterestExpenseDeposits	1870000	USD
CY2020Q1	us-gaap	Interest Expense Deposits InterestExpenseDeposits	9279000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2214193	shares
CY2020Q4	nfbk	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue	4.01
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	13.94
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P3Y11M15D
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	41090	shares
CY2021Q1	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Weighted Average Grant Date Fair Value SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue	3.96
CY2021Q1	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	13.62
CY2021Q1	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	54990	shares
CY2021Q1	nfbk	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageGrantDateFairValue	4.06
CY2021Q1	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	14.69
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2118113	shares
CY2021Q1	nfbk	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue	4.01
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	13.92
CY2021Q1	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P3Y8M15D
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	2101034	shares
CY2021Q1	nfbk	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageGrantDateFairValue	4.00
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	13.91
CY2021Q1	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P3Y8M12D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	104010	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	15.91
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	176930	shares
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	12.59
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod	38470	shares
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue	15.81
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	4022	shares
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue	15.81
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	238448	shares
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue	13.46
CY2021Q1	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	4466000	USD
CY2020Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	5325000	USD
CY2021Q1	nfbk	Other Real Estate Owned Fair Value Disclosure OtherRealEstateOwnedFairValueDisclosure	100000	USD
CY2020Q4	nfbk	Other Real Estate Owned Fair Value Disclosure OtherRealEstateOwnedFairValueDisclosure	0	USD
CY2021Q1	nfbk	Principal Amount Outstanding Of Impaired Loans Heldfor Investment Heldfor Sale PrincipalAmountOutstandingOfImpairedLoansHeldforInvestmentHeldforSale	6500000	USD
CY2020Q4	nfbk	Principal Amount Outstanding Of Impaired Loans Heldfor Investment Heldfor Sale PrincipalAmountOutstandingOfImpairedLoansHeldforInvestmentHeldforSale	7400000	USD
CY2021Q1	nfbk	Estimated Fair Value Of Impaired Loans Held For Investment EstimatedFairValueOfImpairedLoansHeldForInvestment	4500000	USD
CY2020Q4	nfbk	Estimated Fair Value Of Impaired Loans Held For Investment EstimatedFairValueOfImpairedLoansHeldForInvestment	5300000	USD
CY2021Q1	nfbk	Impaired Financing Receivable Reserve Increase Decrease ImpairedFinancingReceivableReserveIncreaseDecrease	3000	USD
CY2020Q1	nfbk	Impaired Financing Receivable Reserve Increase Decrease ImpairedFinancingReceivableReserveIncreaseDecrease	-79000	USD
CY2021Q1	nfbk	Impaired Financing Receivables Charge Off ImpairedFinancingReceivablesChargeOff	2400000	USD
CY2020Q1	nfbk	Impaired Financing Receivables Charge Off ImpairedFinancingReceivablesChargeOff	90000	USD
CY2021Q1	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	100000	USD
CY2020Q4	us-gaap	Loans Held For Sale Fair Value Disclosure LoansHeldForSaleFairValueDisclosure	19895000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	18677000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	4551000	USD
CY2021Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	49528419	shares
CY2020Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46791768	shares
CY2021Q1	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	105225	shares
CY2020Q1	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	191698	shares
CY2021Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49633644	shares
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	42700000	USD
CY2020Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46983466	shares
CY2021Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.38
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.10
CY2021Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.38
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.10
CY2021Q1	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1002377	shares
CY2020Q1	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1001828	shares
CY2021Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	35700000	USD
CY2021Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	42100000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	36700000	USD
CY2021Q1	us-gaap	Operating Lease Cost OperatingLeaseCost	1455000	USD
CY2020Q1	us-gaap	Operating Lease Cost OperatingLeaseCost	1439000	USD
CY2021Q1	us-gaap	Variable Lease Cost VariableLeaseCost	1235000	USD
CY2020Q1	us-gaap	Variable Lease Cost VariableLeaseCost	544000	USD
CY2021Q1	us-gaap	Lease Cost LeaseCost	2690000	USD
CY2020Q1	us-gaap	Lease Cost LeaseCost	1983000	USD
CY2021Q1	us-gaap	Operating Lease Payments OperatingLeasePayments	1708000	USD
CY2020Q1	us-gaap	Operating Lease Payments OperatingLeasePayments	1545000	USD
CY2021Q1	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2020Q1	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	3028000	USD
CY2021Q1	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P12Y3M3D
CY2020Q1	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P12Y8M15D
CY2021Q1	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0360
CY2020Q1	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0359
CY2021Q1	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	4669000	USD
CY2021Q1	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	5550000	USD
CY2021Q1	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	5504000	USD
CY2021Q1	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5067000	USD
CY2021Q1	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4710000	USD
CY2021Q1	nfbk	Lessee Operating Lease Liability Payments Due After Year Four LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour	28196000	USD
CY2021Q1	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	53696000	USD
CY2021Q1	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	11629000	USD
CY2021Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	42067000	USD
CY2021Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1197000	USD
CY2020Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1120000	USD
CY2021Q1	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	848000	USD
CY2020Q1	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	876000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Gain Loss DebtSecuritiesAvailableForSaleGainLoss	97000	USD
CY2020Q1	us-gaap	Debt Securities Available For Sale Gain Loss DebtSecuritiesAvailableForSaleGainLoss	-13000	USD
CY2021Q1	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	364000	USD
CY2020Q1	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-1992000	USD
CY2021Q1	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	0	USD
CY2020Q1	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	76000	USD
CY2021Q1	us-gaap	Revenue Not From Contract With Customer Other RevenueNotFromContractWithCustomerOther	130000	USD
CY2020Q1	us-gaap	Revenue Not From Contract With Customer Other RevenueNotFromContractWithCustomerOther	41000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	2636000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	108000	USD
CY2021Q1	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	0	USD
CY2020Q1	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	76000	USD

Files In Submission

Name	View Source	Status
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$NFBK
Northfield Bancorp, Inc. Stock $nfbk

2021 Q1 Form 10-Q Financial Statement

#000149322521000066 Filed on May 10, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NFBK Northfield Bancorp, Inc. Stock $nfbk

2021 Q1 Form 10-Q Financial Statement

#000149322521000066 Filed on May 10, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NFBK
Northfield Bancorp, Inc. Stock $nfbk