Note 9 - Borrowed Funds - Terms of the Securities Issued by the Trusts (Details)	12 Months Ended
Dec. 31, 2016
Flushing Financial Capital Trust II [Member] \| Capital Securities [Member]
Issue Date	Jun. 20, 2007
Initial Rate	7.14%
First Reset Date	Sep. 01, 2012
Spread over 3-month LIBOR	1.41%
Maturity Date	Sep. 01, 2037
Flushing Financial Capital Trust III [Member] \| Capital Securities [Member]
Issue Date	Jun. 21, 2007
Initial Rate	6.89%
First Reset Date	Jun. 15, 2012
Spread over 3-month LIBOR	1.44%
Maturity Date	Sep. 15, 2037
Flushing Financial Capital Trust IV [Member] \| Capital Securities [Member]
Issue Date	Jul. 03, 2007
Initial Rate	6.85%
First Reset Date	Jul. 30, 2012
Spread over 3-month LIBOR	1.42%
Maturity Date	Jul. 30, 2037
Subordinated Debt [Member]
Issue Date	Dec. 12, 2016
Initial Rate	5.25%
First Reset Date	Dec. 15, 2021
First Call Date	Dec. 15, 2021
Maturity Date	Dec. 15, 2026
Subordinated Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Spread over 3-month LIBOR	3.44%

First reset date for the interest rate on the debt instrument.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

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- Definition

Earliest date before maturity when the issuer can call the outstanding debt instrument for repayment or conversion to equity, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
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-Paragraph 3
-Subparagraph (e)
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Contractual interest rate for funds borrowed, under the debt agreement.

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Date the debt instrument was issued, in CCYY-MM-DD format.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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