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Computation of Basic and Diluted Net Income Per Common Share (Parenthetical) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified | 12 Months Ended
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Dec. 31, 2014
Convertible Notes |
Net Income Loss Per Common Share |
Initial debt conversion price | $ 5.48 us-gaap_DebtInstrumentConvertibleConversionPrice1 / us-gaap_DebtInstrumentAxis = ter_ConvertibleNoteMember
Shares that would be issued upon conversion | 34.7 ter_AntidilutionAdjustmentsOfConvertibleNoteHedges / us-gaap_DebtInstrumentAxis = ter_ConvertibleNoteMember
Convertible Notes Hedge Warrant |
Net Income Loss Per Common Share |
Initial debt conversion price | $ 7.67 us-gaap_DebtInstrumentConvertibleConversionPrice1 / us-gaap_DebtInstrumentAxis = ter_ConvertibleNotesHedgeAndWarrantMember
Shares that would be issued upon conversion | 34.7 ter_AntidilutionAdjustmentsOfConvertibleNoteHedges / us-gaap_DebtInstrumentAxis = ter_ConvertibleNotesHedgeAndWarrantMember

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- Definition Antidilution adjustments of convertible note hedges. + References No definition available. + Details
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Balance Type: | na
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- Details
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Namespace Prefix: | ter_
Data Type: | xbrli:stringItemType
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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
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- Details
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- Details
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Balance Type: |
Period Type: |