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Business process improvement cost.

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Additional information about the entity or its reportable segments that may contribute to an understanding of the enterprise.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of investment in equity security without readily determinable fair value.

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Basis of Presentation - Additional Information (Detail) $ in Thousands	3 Months Ended	4 Months Ended		12 Months Ended
	Dec. 30, 2023 USD ($)	Apr. 19, 2025 USD ($) Segment	Apr. 20, 2024 USD ($)	Dec. 28, 2024 USD ($)	Oct. 05, 2024 USD ($)	Jul. 15, 2023 USD ($)	Jul. 16, 2022 USD ($)
Basis of Presentation [Line Items]
Number of operating segments \| Segment		1
Segment reporting, description		The company has identified two operating segments based on how business activities are managed and evaluated, legacy Flowers Foods and Simple Mills. Simple Mills qualifies as an operating segment as it meets the criteria of being a business and has discrete financial information available that is regularly reviewed by the chief executive officer (the "CEO"), who is the chief operating decision maker (the "CODM"), to assess the performance and allocate resources. As Simple Mills shares similar economic characteristics with legacy Flowers Foods, we aggregate Simple Mills and legacy Flowers Foods as one operating segment for the purposes of determining our one reportable segment.
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]		srt:ChiefExecutiveOfficerMember
Number of reportable segments \| Segment		1
Investment in unconsolidated affiliate		$ 1,481		$ 1,481
Fair value of investment in unconsolidated affiliate			$ 1,500		$ 1,500
Asset impairment charges and equipment relocation costs		5,495	4,000
Recovery related to the sale of equipment		14	60
Investment impairment loss	$ 5,500		4,000
Business Process Improvement Cost		891	$ 3,683
Bailey Street Bakery
Basis of Presentation [Line Items]
Severance costs		1,300
Asset impairment charges and equipment relocation costs		$ 6,100
Outstanding Trade Receivables \| Wal-Mart/Sam's Club \| Customer Concentration Risk
Basis of Presentation [Line Items]
Concentration risk percentage		19.90%		22.40%
Initial Investment
Basis of Presentation [Line Items]
Fair value of investment in unconsolidated affiliate							$ 9,000
Second Investment
Basis of Presentation [Line Items]
Fair value of investment in unconsolidated affiliate						$ 2,000