v3.25.3

Cover	Nov. 05, 2025
Document Information [Line Items]
Document Type	8-K
Document Period End Date	Nov. 05, 2025
Entity Registrant Name	FAT Brands Inc.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-38250
Entity Tax Identification Number	82-1302696
Entity Address, Address Line One	9720 Wilshire Blvd.
Entity Address, Address Line Two	Suite 500
Entity Address, City or Town	Beverly Hills
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	90212
City Area Code	310
Local Phone Number	319-1850
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Entity Central Index Key	0001705012
Amendment Flag	false
Class A Common Stock
Document Information [Line Items]
Title of 12(b) Security	Class A Common Stock, par value $0.0001 per share
Trading Symbol	FAT
Security Exchange Name	NASDAQ
Class B Common Stock
Document Information [Line Items]
Title of 12(b) Security	Class B Common Stock, par value $0.0001 per share
Trading Symbol	FATBB
Security Exchange Name	NASDAQ
Series B Cumulative Preferred Stock
Document Information [Line Items]
Title of 12(b) Security	Series B Cumulative Preferred Stock, par value $0.0001 per share
Trading Symbol	FATBP
Security Exchange Name	NASDAQ

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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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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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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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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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fat Brands, Inc 8-K