Regulatory Capital (Details)	Sep. 30, 2023	Dec. 31, 2022
Savings Bank [Member]
Capital Conservation Buffer	6.02%	6.37%
Holding Company
Capital Conservation Buffer	4.83%	5.25%

Represents the capital conservation buffer, above the regulatory minimum capital ratios.

No definition available.

Name:	ffic_CapitalConservationBuffer
Namespace Prefix:	ffic_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant