Leases - Lease term and discount rates information (Details) - Hman Group holdings Inc and subsidiaries	Mar. 27, 2021	Dec. 26, 2020	Dec. 28, 2019
Lessee, Lease, Description [Line Items]
Operating Lease Weighted average remaining lease term	7 years 1 month 24 days	7 years 2 months 9 days	7 years 10 months 17 days
Operating Lease Weighted average discount rate	8.70%	8.28%	7.81%
Finance lease Weighted average remaining lease term	2 years 5 months 9 days	2 years 7 months 10 days	3 years 5 months 16 days
Finance lease Weighted average discount rate	7.14%	7.14%	6.49%

Weighted average discount rate for finance lease calculated at point in time.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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- Definition

Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

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- 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.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

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