Derivative Financial Instruments - Additional Information (Detail) - USD ($)	4 Months Ended
Apr. 19, 2025	Apr. 20, 2024	Dec. 28, 2024
Derivatives, Fair Value [Line Items]
Cash settlement net receipt	$ 4,200,000
Hedge ineffectiveness	0	$ 0
Derivative instrument, asset	3,496,000		$ 4,046,000
Derivative instrument, liability	3,400,000		2,100,000
Interest derivatives	1,066,000		(567,000)
Interest Rate Risk
Derivatives, Fair Value [Line Items]
Interest derivatives	$ 0		$ 7,686,000

Derivative cash settlement net receipt of closed interest rate swaps.

No definition available.

Name:	flo_DerivativeCashSettlementNetReceipt
Namespace Prefix:	flo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 13
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-13

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 20
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-20

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483466/210-20-50-3

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4C

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Fair value as of the balance sheet date of all price risk derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 10
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480463/815-10-45-5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: