XML 116 R101.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Pension and Other Postretirement Benefit Plans - Assets that are Carried at Fair Value, and the Method Used to Determine Fair Value (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Long Corporate Bond Fund [Member] |  |  |
Pooled Separate Accounts |  |  |
Average duration of bonds | 3 months |  |
Retirement Plan [Member] |  |  |
Pooled Separate Accounts |  |  |
Plan Investments | $ 19,220 | $ 19,065 | $ 26,059
Retirement Plan [Member] | Long Duration Bond Fund [Member] |  |  |
Pooled Separate Accounts |  |  |
Plan Investments | 4,842 | 4,596 |
Retirement Plan [Member] | Long Corporate Bond Fund [Member] |  |  |
Pooled Separate Accounts |  |  |
Plan Investments | 3,907 | 3,754 |
Retirement Plan [Member] | Prudential Short-term [Member] |  |  |
Pooled Separate Accounts |  |  |
Plan Investments | 363 | 262 |
Retirement Plan [Member] | Investment Grade Bond Fund [Member] |  |  |
Pooled Separate Accounts |  |  |
Plan Investments | $ 10,108 | $ 10,453 |

X
- Definition Average duration of bonds compared to benchmark. + References No definition available. + Details
Name: | ffic_DefinedBenefitPlanAverageDurationOfBondsComparedToBenchmark
Namespace Prefix: | ffic_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | ffic_PooledSeparateAccountsAbstract
Namespace Prefix: | ffic_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ffic_LongCorporateBondFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=ffic_RetirementPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ffic_LongDurationBondFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ffic_PrudentialShortTermMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ffic_InvestmentGradeBondFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |