Leases - Supplemental consolidated balance sheet information (Details) - USD ($) $ in Thousands |
Jun. 27, 2026 |
Dec. 27, 2025 |
|---|---|---|
| Operating Leases | ||
| Operating lease right-of-use assets | $ 1,267 | $ 541 |
| Other current liabilities | $ 492 | 619 |
| Other current liabilities - extensible list | Other Liabilities, Current | |
| Operating lease liabilities | $ 800 | 23 |
| Total operating lease liabilities | 1,292 | 642 |
| Finance Leases | ||
| Property and equipment, at cost | 488 | 488 |
| Accumulated depreciation | (419) | (380) |
| Property and equipment, net | $ 69 | 108 |
| Property and equipment, net - extensible list | Property and equipment, net | |
| Other current liabilities | 3 | |
| Other liabilities | $ 0 | 0 |
| Other liabilities - extensible list | Other liabilities | |
| Total finance lease liabilities | $ 3 | |
| Total finance lease liabilities - extensible list | us-gaap:AccruedLiabilitiesCurrent, Other liabilities |
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- Definition Finance Leases [Abstract] No definition available.
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- Definition Operating Lease [Abstract] No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates line item in statement of financial position that includes noncurrent finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates line item in statement of financial position that includes finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after accumulated amortization, of right-of-use asset from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated amortization of right-of-use asset from finance lease. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before accumulated amortization, of right-of-use asset from finance lease. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Indicates line item in statement of financial position that includes finance lease right-of-use asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates line item in statement of financial position that includes current operating lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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