Deferred Revenue and Customer Advances (Detail) - USD ($) $ in Thousands	Apr. 04, 2021	Dec. 31, 2020	Mar. 29, 2020	Dec. 31, 2019
Deferred Revenue Arrangement
Maintenance, service and training	$ 78,321	$ 77,654
Customer advances, undelivered elements and other	67,721	63,438
Extended warranty	53,908	51,929	$ 33,503	$ 30,677
Total deferred revenue and customer advances	$ 199,950	$ 193,021

Total deferred revenue and customer advances.

No definition available.

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- Definition

Deferred revenue and customer advances maintenance service and training.

+ References

No definition available.

+ Details

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- Definition

Deferred revenue and customer advances undelivered elements and other.

+ References

No definition available.

+ Details

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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

Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard 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=68068213&loc=d3e12565-110249

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