FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS (Details) $ in Thousands	Feb. 01, 2020 USD ($)
Fair Value Disclosures [Abstract]
Effect of One Percent Increase on Fair Value of Interest Rate Fair Value Hedging Instruments	$ 60,200
Effect of One Percent Decrease on Fair Value of Interest Rate Fair Value Hedging Instruments	$ 62,900

Effect of One Percent Increase on Fair Value of Interest Rate Fair Value Hedging Instruments

No definition available.

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Namespace Prefix:	unfi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant