Total deferred revenue and customer advances.

No definition available.

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- Definition

Deferred revenue and customer advances maintenance and training.

+ References

No definition available.

+ Details

Name:	ter_DeferredRevenueAndCustomerAdvancesMaintenanceAndTraining
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- Definition

Deferred revenue and customer advances undelivered elements and other.

+ References

No definition available.

+ Details

Name:	ter_DeferredRevenueAndCustomerAdvancesUndeliveredElementsAndOther
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Data Type:	xbrli:monetaryItemType
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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.

+ Details

Name:	us-gaap_DeferredRevenueArrangementLineItems
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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

+ Details

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Deferred Revenue and Customer Advances (Detail) - USD ($) $ in Thousands	Sep. 29, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Dec. 31, 2017
Deferred Revenue Arrangement
Maintenance and training	$ 61,048		$ 58,362
Extended warranty	29,937	$ 28,716	27,422	$ 27,617	$ 25,971	$ 24,438
Customer advances, undelivered performance obligations and other	47,543		24,677
Total deferred revenue and customer advances	$ 138,528		$ 110,461