v3.25.1

Document And Entity Information	Apr. 30, 2025
Document Information [Line Items]
Entity, Registrant Name	The First of Long Island Corporation
Document, Type	8-K/A
Document, Period End Date	Apr. 30, 2025
Entity, Incorporation, State or Country Code	NY
Entity, File Number	001-32964
Entity, Tax Identification Number	11-2672906
Entity, Address, Address Line One	275 Broadhollow Road
Entity, Address, City or Town	Melville
Entity, Address, State or Province	NY
Entity, Address, Postal Zip Code	11747
City Area Code	516
Local Phone Number	671-4900
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Title of 12(b) Security	Common stock, $0.10 par value per share
Trading Symbol	FLIC
Security Exchange Name	NASDAQ
Entity, Emerging Growth Company	false
Amendment Description	Form 8-K/A Earnings Release as of 4-30-2025
Amendment Flag	true
Entity, Central Index Key	0000740663

Description of changes contained within amended document.

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Area code of city

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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Code for the postal or zip code

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Name of the state or province.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Indicate if registrant meets the emerging growth company criteria.

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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Two-character EDGAR code representing the state or country of incorporation.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Name of the Exchange on which a security is registered.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Trading symbol of an instrument as listed on an exchange.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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FIRST OF LONG ISLAND CORP 8-K/A