Note 5 - Loans - Summary of Interest Foregone on Non-accrual Loans and Loans Classified as TDR (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest income that would have been recognized had the loans performed in accordance with their original terms	$ 415	$ 390	$ 809	$ 798
Less: Interest income included in the results of operations	123	156	241	315
Total foregone interest	$ 292	$ 234	$ 568	$ 483

The gross interest income that would have been recorded in the period on troubled debt restructurings and nonaccrual loans, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

No definition available.

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