Contract Liabilities: Performance Obligations (Details)	Dec. 26, 2020 USD ($)
Future estimated revenue to be recognized related to performance obligations
Revenue, remaining performance obligation	$ 8,708,300
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-12-27
Future estimated revenue to be recognized related to performance obligations
Duration of expected recognition period for remaining performance obligation	1 year
Revenue, remaining performance obligation	$ 1,657,400
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-12-26
Future estimated revenue to be recognized related to performance obligations
Duration of expected recognition period for remaining performance obligation	1 year
Revenue, remaining performance obligation	$ 1,512,500
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Future estimated revenue to be recognized related to performance obligations
Duration of expected recognition period for remaining performance obligation	1 year
Revenue, remaining performance obligation	$ 1,341,200
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-12-31
Future estimated revenue to be recognized related to performance obligations
Duration of expected recognition period for remaining performance obligation	1 year
Revenue, remaining performance obligation	$ 1,143,500
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-12-29
Future estimated revenue to be recognized related to performance obligations
Duration of expected recognition period for remaining performance obligation	1 year
Revenue, remaining performance obligation	$ 927,100
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-12-28
Future estimated revenue to be recognized related to performance obligations
Duration of expected recognition period for remaining performance obligation
Revenue, remaining performance obligation	$ 2,126,600

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

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- Definition

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+ References

No definition available.

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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, 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 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

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