Borrowed Funds - Terms of the Securities Issued by the Trusts (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)
Flushing Financial Capital Trust II \| Capital Securities
Issue Date	Jun. 20, 2007
Initial Rate	7.14%
First Reset Date	Sep. 01, 2012
Spread Adjustment	0.26%
Maturity Date	Sep. 01, 2037
Flushing Financial Capital Trust II \| Capital Securities \| SOFR
Spread over 3-month SOFR	1.41%
Flushing Financial Capital Trust III \| Capital Securities
Issue Date	Jun. 21, 2007
Initial Rate	6.89%
First Reset Date	Jun. 15, 2012
Spread Adjustment	0.26%
Maturity Date	Sep. 15, 2037
Flushing Financial Capital Trust III \| Capital Securities \| SOFR
Spread over 3-month SOFR	1.44%
Flushing Financial Capital Trust IV \| Capital Securities
Issue Date	Jul. 03, 2007
Initial Rate	6.85%
First Reset Date	Jul. 30, 2012
Spread Adjustment	0.26%
Maturity Date	Jul. 30, 2037
Flushing Financial Capital Trust IV \| Capital Securities \| SOFR
Spread over 3-month SOFR	1.42%
$1,25,000 subordinate debentures due December 01, 2031
Amount	$ 125,000
Issue Date	Nov. 22, 2021
Initial Rate	3.125%
First Reset Date	Dec. 01, 2026
First Call Date	Dec. 01, 2026
Maturity Date	Dec. 01, 2031
$1,25,000 subordinate debentures due December 01, 2031 \| SOFR
Spread over 3-month SOFR	2.035%
$65,000 Subordinated debentures due September 1, 2032
Amount	$ 65,000
Issue Date	Aug. 24, 2022
Initial Rate	6.00%
First Reset Date	Sep. 01, 2027
First Call Date	Sep. 01, 2027
Maturity Date	Sep. 01, 2032
$65,000 Subordinated debentures due September 1, 2032 \| SOFR
Spread over 3-month SOFR	3.13%

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

No definition available.

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- Definition

Spread adjustment percentage on debt instrument.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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 YYYY-MM-DD format.

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- Definition

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

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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

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

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