Intangible Assets - Components of Purchased Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019
Components of purchased intangible assets
Annual Amortization	$ 16	$ 16
Gross Carrying Value	840	840
Accumulated Amortization	772	756
Net Carrying Value	$ 68	$ 84
Customer Relations
Components of purchased intangible assets
Useful Lives	15 years	15 years
Useful Lives Remaining	4 years 3 months	5 years 3 months
Annual Amortization	$ 16	$ 16
Gross Carrying Value	240	240
Accumulated Amortization	172	156
Net Carrying Value	68	84
Patents
Components of purchased intangible assets
Gross Carrying Value	600	600
Accumulated Amortization	$ 600	$ 600

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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