2.2.0.7 false Consolidated Statements of Cash Flows (Unaudited) (USD $) 0150 - Statement - Consolidated Statements of Cash Flows (Unaudited) true false In Thousands false false 1 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ 3 Cash flows from operating activities: 1 us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities include all transactions and events that are not defined as investing or financing activities. Operating activities generally involve producing and delivering goods and providing services. Cash flows from operating activities are generally the cash effects of transactions and other events that enter into the determination of net income. false 4 Net income 2 us-gaap_NetIncomeLoss us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 true true false false 48902000 48902 false false false 2 true true false false 39542000 39542 false false false xbrli:monetaryItemType monetary The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph d Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A7 -Appendix A Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 10, 15 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28, 29, 30 false 5 Adjustments to reconcile net income to net cash provided by operating activities: 2 us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 6 (Accretion) amortization of fees and discounts, net 3 fnfg_AmortizationOfFeesAndDiscounts fnfg false debit duration Includes (1) The net increase in interest income during the period representing the systematic and rational allocation of... false false false false false false false false false false false verboselabel false 1 false true false false -6227000 -6227 false false false 2 false true false false 7606000 7606 false false false xbrli:monetaryItemType monetary Includes (1) The net increase in interest income during the period representing the systematic and rational allocation of deferred loan origination fees less deferred loan origination costs over the term of the debt arrangement to which they pertain. (2) The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by (used in) operations using the indirect method. (3) The component of interest expense representing the noncash expenses charged against earnings in the period to allocate debt discount and premium, and the costs to issue debt and obtain financing over the related debt instruments. No authoritative reference available. false 7 Provision for credit losses 3 us-gaap_ProvisionForLoanAndLeaseLosses us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 24131000 24131 false false false 2 false true false false 17650000 17650 false false false xbrli:monetaryItemType monetary The sum of the periodic provision charged to operations, based on an assessment of the uncollectibility of the loan and lease portfolio, the offset to which is either added to or deducted from the allowance account for the purpose of reducing loan receivable and leases to an amount that approximates their net realizable value (the amount expected to be collected). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 5 -Paragraph 168, 169, 170 -IssueDate 2006-05-01 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 false 8 Depreciation of premises and equipment 3 us-gaap_DepreciationPremisesAndEquipment us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 9805000 9805 false false false 2 false true false false 6190000 6190 false false false xbrli:monetaryItemType monetary The amount of expense charged against earnings in the period to allocate the cost, net of salvage value, of premises and equipment over their remaining estimated productive lives. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 9 Amortization of intangibles 3 us-gaap_AmortizationOfIntangibleAssets us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 8558000 8558 false false false 2 false true false false 3738000 3738 false false false xbrli:monetaryItemType monetary The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by (used in) operations using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -Subparagraph a(2) false 10 Originations of loans held for sale 3 us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -253523000 -253523 false false false 2 false true false false -242621000 -242621 false false false xbrli:monetaryItemType monetary The amount of cash paid for the origination of mortgages that are held for sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 27 false 11 Proceeds from sales of loans held for sale 3 us-gaap_ProceedsFromSaleOfLoansHeldForSale us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 209820000 209820 false false false 2 false true false false 207905000 207905 false false false xbrli:monetaryItemType monetary The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 102 -Paragraph 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 3, 15, 16, 17, 22, 23, 147, 148, 149 false 12 ESOP and stock-based compensation expense 3 fnfg_EsopAndShareBasedCompensation fnfg false credit duration The amount of compensation cost related to employee stock ownership plan (ESOP) and the aggregate amount of noncash,... false false false false false false false false false false true negated false 1 false true false false 4132000 4132 false false false 2 false true false false 3661000 3661 false false false xbrli:monetaryItemType monetary The amount of compensation cost related to employee stock ownership plan (ESOP) and the aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options and amortization of restricted stock. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. No authoritative reference available. false 13 Deferred income tax expense 3 us-gaap_DeferredIncomeTaxExpenseBenefit us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 20262000 20262 false false false 2 false true false false 1281000 1281 false false false xbrli:monetaryItemType monetary The component of income tax expense for the period representing the net change in the entity's deferred tax assets and liabilities pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section I -Subsection 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 289 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 false 14 Income from bank owned life insurance 3 us-gaap_BankOwnedLifeInsuranceIncome us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -3200000 -3200 false false false 2 false true false false -2630000 -2630 false false false xbrli:monetaryItemType monetary Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies. No authoritative reference available. false 15 Other, net 3 us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet us-gaap true credit duration No definition available. false false false false false false false false false false true negatedtotal false 1 false true false false 14053000 14053 false false false 2 false true false false -7111000 -7111 false false false xbrli:monetaryItemType monetary For entities with classified balance sheets, the net change during the reporting period in the value of other assets or liabilities used in operating activities, that are not otherwise defined in the taxonomy. For entities with unclassified balance sheets, the net change during the reporting period in the value of all other assets or liabilities used in operating activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 true 16 Net cash provided by operating activities 2 us-gaap_NetCashProvidedByUsedInOperatingActivities us-gaap true na duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 76713000 76713 false false false 2 false true false false 35211000 35211 false false false xbrli:monetaryItemType monetary The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities generally involve producing and delivering goods and providing services. Operating activity cash flows include transactions, adjustments, and changes in value that are not defined as investing or financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 true 17 Cash flows from investing activities: 1 us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 18 Proceeds from maturities of securities available for sale 2 fnfg_ProceedsFromMaturitiesOfAvailableForSaleSecurities fnfg false debit duration The cash inflow associated with maturities (principal being due) on securities not classified as either held-to-maturity... false false false false false false false false false false false verboselabel false 1 false true false false 314431000 314431 false false false 2 false true false false 129308000 129308 false false false xbrli:monetaryItemType monetary The cash inflow associated with maturities (principal being due) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities. No authoritative reference available. false 19 Proceeds from sale of securities available for sale 2 us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 121524000 121524 false false false 2 false true false false 995000 995 false false false xbrli:monetaryItemType monetary The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph a Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 18 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph b false 20 Principal payments received on securities available for sale 2 fnfg_ProceedsFromPrepaymentsAndCallsOfAvailableForSaleSecurities fnfg false debit duration The cash inflow associated with prepayments and calls (requests of early payments) on securities not classified as either... false false false false false false false false false false false verboselabel false 1 false true false false 409737000 409737 false false false 2 false true false false 237576000 237576 false false false xbrli:monetaryItemType monetary The cash inflow associated with prepayments and calls (requests of early payments) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities. No authoritative reference available. false 21 Purchases of securities available for sale 2 us-gaap_PaymentsToAcquireAvailableForSaleSecurities us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -2420695000 -2420695 false false false 2 false true false false -2024463000 -2024463 false false false xbrli:monetaryItemType monetary The cash outflow to acquire debt and equity securities not classified as either held-to-maturity securities or trading securities which would be classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 17 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 18 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 17 -Subparagraph a false 22 Principal payments received on securities held to maturity 2 us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 100396000 100396 false false false 2 false true false false 1648000 1648 false false false xbrli:monetaryItemType monetary The cash inflow associated with the maturity, prepayments and calls (requests for early payments) of debt securities designated as held-to-maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph a false 23 Purchases of securities held to maturity 2 us-gaap_PaymentsToAcquireHeldToMaturitySecurities us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -51752000 -51752 false false false 2 false true false false -400062000 -400062 false false false xbrli:monetaryItemType monetary The cash outflow to acquire a debt financial instrument for which the entity has the ability and intent to hold until maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 17 -Subparagraph a false 24 Net (increase) decrease in loans and leases 2 us-gaap_PaymentsForProceedsFromLoansAndLeases us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -46442000 -46442 false false false 2 false true false false 31494000 31494 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) for the net change in the beginning and end of period of loan and lease balances which are not originated or purchased specifically for resale. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15, 16, 17 false 25 Acquisitions, net of cash and cash equivalents 2 us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false 1148646000 1148646 false false false 2 false true false false -237000 -237 false false false xbrli:monetaryItemType monetary The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15, 17 false 26 Other, net 2 us-gaap_PaymentsForProceedsFromOtherInvestingActivities us-gaap true credit duration No definition available. false false false false false false false false false false true negatedtotal false 1 false true false false -62805000 -62805 false false false 2 false true false false -39530000 -39530 false false false xbrli:monetaryItemType monetary The net cash outflow (inflow) from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 true 27 Net cash used in investing activities 2 us-gaap_NetCashProvidedByUsedInInvestingActivities us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false -486960000 -486960 false false false 2 false true false false -2063271000 -2063271 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) from investing activity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 true 28 Cash flows from financing activities: 1 us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 29 Net increase in deposits 2 us-gaap_IncreaseDecreaseInDeposits us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 101190000 101190 false false false 2 false true false false 296415000 296415 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) for the net change in the beginning and end of period deposits balances. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 13 -IssueDate 2006-05-01 false 30 (Repayments of) proceeds from short-term borrowings, net 2 us-gaap_ProceedsFromRepaymentsOfShortTermDebt us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false -338307000 -338307 false false false 2 false true false false 1658454000 1658454 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) for borrowing having initial term of repayment within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 false 31 Proceeds from long-term borrowings 2 us-gaap_ProceedsFromIssuanceOfLongTermDebt us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 946534000 946534 false false false 2 false false false false 0 0 false false false xbrli:monetaryItemType monetary The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph b false 32 Repayments of long-term borrowings 2 us-gaap_RepaymentsOfLongTermDebt us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -150000000 -150000 false false false 2 false true false false -4821000 -4821 false false false xbrli:monetaryItemType monetary The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph b false 33 Proceeds from exercise of stock options 2 us-gaap_ProceedsFromStockOptionsExercised us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 1216000 1216 false false false 2 false true false false 51000 51 false false false xbrli:monetaryItemType monetary The cash inflow associated with the amount received from holders exercising their stock options. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph i Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph a false 34 Excess tax benefit (expense) from stock-based compensation 2 us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 892000 892 false false false 2 false true false false -82000 -82 false false false xbrli:monetaryItemType monetary Reductions in the entity's income taxes that arise when compensation cost (from non-qualified share-based compensation) recognized on the entity's tax return exceeds compensation cost from share-based compensation recognized in financial statements. This element represents the cash inflow reported in the enterprise's financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph i Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 00-15 -Paragraph 3 false 35 Issuance of common stock in follow-on stock offering, net 2 us-gaap_ProceedsFromIssuanceOfCommonStock us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false true false false 360731000 360731 false false false xbrli:monetaryItemType monetary The cash inflow from the additional capital contribution to the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph a false 36 Repurchase of common stock warrant 2 us-gaap_PaymentsForRepurchaseOfWarrants us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false false false false 0 0 false false false 2 false true false false -2700000 -2700 false false false xbrli:monetaryItemType monetary The aggregate amount paid by the entity to reacquire the right to purchase equity shares at predetermined price, usually issued together with corporate debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a false 37 Redemption of preferred stock 2 us-gaap_PaymentsForRepurchaseOfRedeemablePreferredStock us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false false false false 0 0 false false false 2 false true false false -184011000 -184011 false false false xbrli:monetaryItemType monetary The cash outflow for reacquisition of callable preferred stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a false 38 Dividends paid on cumulative preferred stock 2 us-gaap_PaymentsOfDividendsPreferredStockAndPreferenceStock us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false false false false 0 0 false false false 2 false true false false -4754000 -4754 false false false xbrli:monetaryItemType monetary The cash outflow for the return on capital for preferred shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a false 39 Dividends paid on common stock 2 us-gaap_PaymentsOfDividendsCommonStock us-gaap true credit duration No definition available. false false false false false false false false false false true negatedtotal false 1 false true false false -54841000 -54841 false false false 2 false true false false -36702000 -36702 false false false xbrli:monetaryItemType monetary The cash outflow from the distribution of an entity's earnings in the form of dividends to common shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a true 40 Net cash provided by financing activities 2 us-gaap_NetCashProvidedByUsedInFinancingActivities us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 506684000 506684 false false false 2 false true false false 2082581000 2082581 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) from financing activity for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 true 41 Net (decrease) increase in cash and cash equivalents 1 us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 96437000 96437 false false false 2 false true false false 54521000 54521 false false false xbrli:monetaryItemType monetary The net change between the beginning and ending balance of cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 false 42 Cash and cash equivalents at beginning of period 1 fnfg_CashAndCashEquivalentsAndRestrictedCashAtCarryingValue fnfg false debit instant Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of... false false false false false false false false true false false periodstartlabel false 1 false true false false 236268000 236268 false false false 2 false true false false 114551000 114551 false false false xbrli:monetaryItemType monetary Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents. Also includes the carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. No authoritative reference available. false 43 Cash and cash equivalents at end of period 1 fnfg_CashAndCashEquivalentsAndRestrictedCashAtCarryingValue fnfg false debit instant Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of... false false false false false false false false false true false periodendlabel false 1 false true false false 332705000 332705 false false false 2 false true false false 169072000 169072 false false false xbrli:monetaryItemType monetary Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents. Also includes the carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. No authoritative reference available. false 44 Cash paid during the period for: 1 us-gaap_SupplementalCashFlowInformationAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 45 Income taxes 2 us-gaap_IncomeTaxesPaidNet us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 30078000 30078 false false false 2 false true false false 22663000 22663 false false false xbrli:monetaryItemType monetary The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 29 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 27 -Subparagraph f false 46 Interest expense 2 us-gaap_InterestPaidNet us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 64301000 64301 false false false 2 false true false false 64792000 64792 false false false xbrli:monetaryItemType monetary The amount of cash paid during the current period for interest owed on money borrowed, net of interest capitalized. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 29 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 27 -Subparagraph e false 47 Acquisition of noncash assets and liabilities: 1 fnfg_AcquisitionOfNoncashAssetsAndLiabilitiesAbstract fnfg false na duration Acquisition of noncash assets and liabilities. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string Acquisition of noncash assets and liabilities. false 48 Assets acquired 2 us-gaap_FairValueOfAssetsAcquired us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 4146768000 4146768 false false false 2 false true false false 237000 237 false false false xbrli:monetaryItemType monetary The fair value of assets acquired in noncash investing or financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 false 49 Liabilities assumed 2 us-gaap_LiabilitiesAssumed us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 4995993000 4995993 false false false 2 false false false false 0 0 false false false xbrli:monetaryItemType monetary The fair value of liabilities assumed in Noncash investing or financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 false 50 Loans transferred to other real estate owned 1 us-gaap_TransferOtherRealEstate us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 4009000 4009 false false false 2 false true false false 4606000 4606 false false false xbrli:monetaryItemType monetary Value of real estate transferred in noncash transactions during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 false 51 Securities available for sale purchased not settled 1 fnfg_SecuritiesAvailableForSalePurchasedNotSettled fnfg false debit duration Securities available for sale purchased not settled. false false false false false false false false false false false verboselabel false 1 false true false false 40394000 40394 false false false 2 false true false false 86903000 86903 false false false xbrli:monetaryItemType monetary Securities available for sale purchased not settled. No authoritative reference available. false 52 Capital lease obligation 1 us-gaap_CapitalLeaseObligationsIncurred us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 true true false false 11928000 11928 false false false xbrli:monetaryItemType monetary The increase during the period in capital lease obligations due to entering into new capital leases. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 false 2 50 false Thousands UnKnown UnKnown false true