The amount of charge-offs (recoveries) of loans held for sale.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of net recoveries (charge-offs) during the period on delinquent and non-performing loans during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Proceeds from the sales of delinquent and non-performing loans sold during the period.

+ References

No definition available.

+ Details

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

- Definition

Delinquent and non-performing loans sold during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Net gain (loss) on delinquent and non-performing loans during the period.

+ References

No definition available.

+ Details

Name:	ffic_DelinquentAndNonperformingLoansNetGainLoss
Namespace Prefix:	ffic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of gain (loss) realized from the sale of loans held for sale.

+ References

No definition available.

+ Details

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

- Definition

The number of loans sold during the period that were held for sale.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3337-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3461-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

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- Details

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Note 6 - Loans Held for Sale - Delinquent and Non-performing Loans Sold During the Period Indicated (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)
Nonperforming Financial Instruments [Member]
Loans sold	2	1	6	6
Proceeds	$ 2,065	$ 335	$ 4,529	$ 2,125
Net gain (loss)	$ 28		$ (235)
Loans sold	9		9
Proceeds	$ 5,671		$ 5,671
Net gain (loss)	$ 393		$ 393
Net (charge-offs) recoveries		$ (4)		$ (37)
Performing Financial Instruments [Member]
Loans sold		11		14
Proceeds		$ 16,050		$ 19,450
Net gain (loss)		34		216
Net (charge-offs) recoveries
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold	2		3
Proceeds	$ 2,065		$ 3,565
Net gain (loss)	$ 28		$ (235)
Commercial Real Estate Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Loans sold				1
Proceeds				$ 335
Net gain (loss)
Loans sold		5		5
Proceeds		$ 8,451		$ 8,451
Net gain (loss)		(21)		(21)
Net (charge-offs) recoveries				(4)
Net (charge-offs) recoveries
Commercial Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold		1
Proceeds		$ 335
Net gain (loss)
Net (charge-offs) recoveries		$ (4)
Multi-family Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold			3
Proceeds			$ 964
Net gain (loss)
Multi-family Residential Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Loans sold		2		2
Proceeds		$ 6,080		$ 6,080
Net gain (loss)		(14)		(14)
Net (charge-offs) recoveries
One-To-Four Family - Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold				5
Proceeds				$ 1,790
Net gain (loss)
Net (charge-offs) recoveries				$ (33)
Small Business Administration Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold	9		9
Proceeds	$ 5,671		$ 5,671
Net gain (loss)	$ 393		$ 393
Small Business Administration Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Loans sold		4		7
Proceeds		$ 1,519		$ 4,919
Net gain (loss)		69		250
Net (charge-offs) recoveries