The amount outstanding of advances from FHLB and Letters of Credit.

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Represents the percentage of advances outstanding which must be collateralized pursuant to the collateral agreement.

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No definition available.

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The percentage of average cost to debt.

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The extended maturity on advances as a result of modification without incurring a prepayment penalty.

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The prepayment penalty on securities sold under agreements to repurchase.

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Face (par) amount of debt instrument at time of issuance.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Gross amount of debt extinguished.

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No definition available.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of repayments and penalties incurred in the satisfaction or roll-over of Federal Home Loan Bank (FHLB) advance.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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No definition available.

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The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

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Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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Stated interest rate of the subordinated debt.

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No definition available.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Note 9 - Borrowed Funds (Details Textual) - USD ($) $ in Thousands				12 Months Ended
	Jul. 03, 2007	Jun. 21, 2007	Jun. 20, 2007	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 30, 2015
Prepayment Penalty on Advances				$ 10,400		$ 5,200
Advances from Federal Home Loan Banks and Letters of Credit				$ 1,506,400
Advances Outstanding, Collateral Agreement, Collateralized Percentage				110.00%
Proceeds from Issuance of Subordinated Long-term Debt				$ 73,402	$ 0	0
Subordinated Borrowing, Interest Rate				5.25%
Subordinated Debt				$ 73,414	0
Secured Debt, Repurchase Agreements				0	116,000
Capital Securities [Member] \| Flushing Financial Capital Trust III [Member]
Proceeds from Issuance of Debt		$ 20,600
Capital Securities [Member] \| Flushing Financial Capital Trust II [Member]
Proceeds from Issuance of Debt			$ 20,600
Capital Securities [Member] \| Flushing Financial Capital Trust IV [Member]
Proceeds from Issuance of Debt	$ 20,600
Unsecured Line of Credit [Member]
Long-term Line of Credit				100,000
Securities Sold under Agreements to Repurchase [Member]
Extinguishment of Debt, Amount				$ 78,000		$ 30,000
Debt, Average Cost, Percentage				3.80%		4.98%
Federal Home Loan Bank of New York [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Repayment and Penalties				$ 130,000	$ 80,000	$ 66,900
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate				2.82%	3.46%	2.98%	4.41%
Extended Average Maturity Without Prepayment Penalty				2 years 109 days
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available				$ 2,703,100
Federal Home Loan Bank Advances [Member] \| Minimum [Member] \| Federal Home Loan Bank of New York [Member]
Debt Instrument, Term				1 day
Federal Home Loan Bank Advances [Member] \| Maximum [Member] \| Federal Home Loan Bank of New York [Member]
Debt Instrument, Term				5 years
Subordinated Debt [Member]
Debt Instrument, Face Amount				$ 75,000
Debt Issuance Costs, Net				$ 1,600