Business Combination, Consideration Transferred, Exchange Offer In Shares, Option One

No definition available.

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- Definition

Business Combination, Consideration Transferred, Exchange Offer In Shares, Option Two

+ References

No definition available.

+ Details

Name:	prmw_BusinessCombinationConsiderationTransferredExchangeOfferInSharesOptionTwo
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- Definition

Payments To Acquire Businesses, Price Per Share, Option One

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
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Period Type:	instant

- Definition

Payments To Acquire Businesses, Price Per Share, Option Two

+ References

No definition available.

+ Details

Name:	prmw_PaymentsToAcquireBusinessesPricePerShareOptionTwo
Namespace Prefix:	prmw_
Data Type:	num:perShareItemType
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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

Name:	us-gaap_BusinessAcquisitionLineItems
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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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- Definition

The number of countries in which the entity operates as of balance sheet date.

+ References

No definition available.

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Name:	us-gaap_BusinessAcquisitionAxis=prmw_LegacyPrimoAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions - Additional Information (Details) $ / shares in Units, $ in Millions	3 Months Ended	4 Months Ended	6 Months Ended
	Jun. 27, 2020 USD ($) country	Jun. 27, 2020 USD ($) country	Jun. 27, 2020 USD ($) country	Mar. 02, 2020 country $ / shares
Business Acquisition [Line Items]
Number of countries, country footprint \| country	21	21	21
Legacy Primo Acquisition
Business Acquisition [Line Items]
Number of countries, country footprint \| country				21
Cash per share, election option one (in dollars per share) \| $ / shares				$ 14.00
Share exchange offer one (in shares)				1.0229
Cash per share, election option two (in dollars per share) \| $ / shares				$ 5.04
Share exchange offer two (in shares)				0.6549
Business combination revenue, since acquisition date		$ 116.4
Business combination, net income, since acquisition date		$ 1.4
Acquisition-related costs	$ 2.9		$ 21.7