Income taxes - Narrative (Details) - USD ($) $ in Millions	Dec. 28, 2024	Dec. 30, 2023
Income Tax Contingency [Line Items]
Operating loss carryforwards, valuation allowance	$ 2.9	$ 2.9
Domestic Tax Jurisdiction
Income Tax Contingency [Line Items]
Operating loss carryforwards	19.5
State and Local Jurisdiction
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 11.8

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No definition available.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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- Definition

The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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