Note 5 - Loans (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($)	Mar. 31, 2016	Dec. 31, 2016 USD ($)
Fair Value of Collateral Dependent Loans as a Percentage of Appraised or Estimated Value of Collateral	85.00%
Collateral Dependent Impaired Loans Measured by Third Party Appraisals	$ 44,300
Collateral Dependent Impaired Loans Measured by Third Party Appraisals Percentage	82.30%
Collateral Dependent Impaired Loans Measured Internally	$ 9,500
Collateral Dependent Impaired Loans Measured Internally Percentage	17.70%
Commitments and Contingencies
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 0
Financing Receivable, Modifications, Number of Contracts	0	0
TDR Loans Transferred to Non-performing, Number of Contracts	0	0
Extension of Credit [Member]
Commitments and Contingencies	$ 63,200
Extension of Lines of Credit [Member]
Commitments and Contingencies	$ 241,800

The amount of collateral dependent impaired loans that are measured by third party appraisals.

No definition available.

Name:	ffic_CollateralDependentImpairedLoansMeasuredByThirdPartyAppraisals
Namespace Prefix:	ffic_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of collateral dependent impaired loans that are measured by third party appraisals. That is expressed as a percentage.

+ References

No definition available.

+ Details

Name:	ffic_CollateralDependentImpairedLoansMeasuredByThirdPartyAppraisalsPercentage
Namespace Prefix:	ffic_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of collateral dependent impaired loans that are measured internally.

+ References

No definition available.

+ Details

Name:	ffic_CollateralDependentImpairedLoansMeasuredInternally
Namespace Prefix:	ffic_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of collateral dependent impaired loans that are measured internally and expressed as a percentage.

+ References

No definition available.

+ Details

Name:	ffic_CollateralDependentImpairedLoansMeasuredInternallyPercentage
Namespace Prefix:	ffic_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The fair value of a collateral dependent loan expressed as a percentage of appraised or estimated value of collateral.

+ References

No definition available.

+ Details

Name:	ffic_FairvalueOfCollateralDependentLoansAsAPercentageOfAppraisedOrEstimatedValueOfCollateral
Namespace Prefix:	ffic_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of TDR loans transferred to non-performing loans during the period.

+ References

No definition available.

+ Details

Name:	ffic_TDRLoansTransferredToNonPerformingNumberOfContracts
Namespace Prefix:	ffic_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),19)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.17)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommitmentsAndContingencies
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554

+ Details

Name:	us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_SupplyCommitmentAxis=ffic_ExtensionOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SupplyCommitmentAxis=ffic_ExtensionOfLinesOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: