Commitments and Contingencies - Activity in Warranty Provisions Account (Detail) - USD ($) $ in Thousands	12 Months Ended
Jan. 01, 2022	Jan. 02, 2021
Commitments and Contingencies Disclosure [Abstract]
Beginning balance	$ 480	$ 1,022
Expenditures incurred under warranties	(622)	(493)
Expenditures incurred under warranties included in discontinued operations	(89)	(19)
Accruals for product warranties	502	237
Accruals for product warranties included in discontinued operations	122	43
Adjustments to previously existing warranty accruals	31	(306)
Adjustments to previously existing warranty accruals included in discontinued operations	(31)	(4)
Sale of Photonics division	(47)
Ending balance	$ 346	$ 480

Accruals For Product Warranties Included In Discontinued Operations.

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- Definition

Adjustments To Previously Existing Warranty Accruals Included In Discontinued Operations.

+ References

No definition available.

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- Definition

Expenditures Incurred Under Warranties Included In Discontinued Operations.

+ References

No definition available.

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- Definition

Sale Of Photonics Division.

+ References

No definition available.

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- References

No definition available.

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- Definition

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3,4))
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1),(c)(5)
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

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- Definition

Amount of increase (decrease) in the standard product warranty accrual from changes in estimates attributable to preexisting product warranties. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(4))
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

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- Definition

Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3))
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

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