Name:	ter_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentTax
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The tax effect from the total of net (gain) loss, prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

No definition available.

Name:	ter_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansTax
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The tax effect from accumulated adjustment, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains (losses).

No definition available.

Name:	ter_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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.

No definition available.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65896914&loc=d3e39076-109324

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Name:	us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65896914&loc=d3e39076-109324

Name:	us-gaap_OtherComprehensiveIncomeLossTax
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).