Name:	ter_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice
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Period Type:	duration

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

No definition available.