Amortized cost excluding accrued interest, of financing receivable 12 months after modification for debtor experiencing financial difficulty.

No definition available.

+ Details

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Namespace Prefix:	ffic_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

No definition available.

+ Details

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

- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

No definition available.

+ Details

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Namespace Prefix:	ffic_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Loans - Loans Modifications Made to Borrowers and Payment Status (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($) contract	Sep. 30, 2022 contract	Sep. 30, 2023 USD ($) contract	Sep. 30, 2022 contract	Dec. 31, 2022 contract
Number of TDR loan modifications \| contract		1		6
Nonperforming Financial Instruments [Member]
Number of TDR loan modifications \| contract					2
Payment Deferral
Number of TDR loan modifications \| contract	3		3
Amortized Cost Basis	$ 1,638		$ 1,638
Payment Deferral \| Current
Total modified payment status of borrowers	1,638		1,638
Payment Deferral \| 30-89 Days Past Due
Total modified payment status of borrowers	1,494		1,494
Payment Deferral \| Total Past Due
Total modified payment status of borrowers	$ 3,132		$ 3,132
Other Than Insignificant Payment Delay
Number of TDR loan modifications \| contract			1
Amortized Cost Basis			$ 1,494
Commercial Business and Other
Number of TDR loan modifications \| contract		1		5
Commercial Business and Other \| Payment Deferral
Number of TDR loan modifications \| contract	3		3
Amortized Cost Basis	$ 1,638		$ 1,638
Total Class of Financing Receivables, percentage	0.10%		0.10%
Commercial Business and Other \| Payment Deferral \| Current
Total modified payment status of borrowers	$ 1,638		$ 1,638
Commercial Business and Other \| Payment Deferral \| Total Past Due
Total modified payment status of borrowers	1,638		1,638
Small Business Administration
Number of TDR loan modifications \| contract				1
Small Business Administration \| Payment Deferral \| 30-89 Days Past Due
Total modified payment status of borrowers	1,494		1,494
Small Business Administration \| Payment Deferral \| Total Past Due
Total modified payment status of borrowers	$ 1,494		$ 1,494
Small Business Administration \| Other Than Insignificant Payment Delay
Number of TDR loan modifications \| contract			1
Amortized Cost Basis			$ 1,494
Total Class of Financing Receivables, percentage			6.80%