Maximum length of time until the line of credit matures.

No definition available.

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Namespace Prefix:	ffic_
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Balance Type:	na
Period Type:	duration

- Definition

Loan commitments expiration period.

+ References

No definition available.

+ Details

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

- Definition

Reflects the amount of cash required to fully fund agreements to provide credit to borrowers.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Reflects the weighted average interest rate on commitments to advance to borrowers and lessees at interest rates that increase or decrease depending on certain facts or circumstances.

+ References

No definition available.

+ Details

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- Definition

Reflects the weighted average interest rate associated with agreements to provide advances to borrowers and lessees at stated interest rates.

+ References

No definition available.

+ Details

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- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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Balance Type:	debit
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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

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- Definition

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at interest rates that increase or decrease depending on certain facts or circumstances.

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
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Note 15 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Jul. 31, 2007	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans and Leases Receivable, Commitments, Fixed Rates		$ 26,600
Loans and Leases Receivable, Commitments, Weighted Average Rate of Interest		4.80%
Loans and Leases Receivable, Commitments, Variable Rates		$ 286,900
Loans and Leases Receivable, Commitments, Variable Rates, Weighted Average Rate		5.45%
Loan Commitments, Expiration		90 days
Line of Credit, Maturity, Max		1 year 180 days
Operating Leases, Rent Expense, Total		$ 6,100	$ 6,300	$ 5,800
Operating Leases, Future Minimum Payments Due, Total		60,234
Other Equipment and Cars [Member] \| Equipment Leases [Member]
Operating Leases, Future Minimum Payments Due, Total		500
Home Equity Line of Credit [Member]
Loans and Leases Receivable, Commitments, Credit		$ 248,700
Line of Credit, Maturity, Max		10 years
Letter of Credit Pledged as Collateral [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments		$ 659,600	$ 402,100
Capital Securities [Member] \| Flushing Financial's Capital Trusts [Member]
Proceeds from Issuance of Debt	$ 61,900
Mortgages [Member]
Loans and Leases Receivable, Commitments, Credit		$ 64,900