Regulatory Capital (Details)	Mar. 31, 2024	Dec. 31, 2023
Savings Bank [Member]
Capital Conservation Buffer	5.08%	4.81%
Holding Company
Capital Conservation Buffer	5.02%	4.93%

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