Additional aggregate principal amount.

No definition available.

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- Definition

Class Of Warrant Or Right Exercise Price Of Warrants Or Rights Issued

+ References

No definition available.

+ Details

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- Definition

Class Of Warrant Or Right Number Of Securities Called By Warrants

+ References

No definition available.

+ Details

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- Definition

Common Shares Attributable To Conversion Of Debt Instrument

+ References

No definition available.

+ Details

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Namespace Prefix:	ter_
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- Definition

Common Stock Shares Excluding Subject To Conversion

+ References

No definition available.

+ Details

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- Definition

Number Of Trading Period Consider For Weight Average Price Of Common Stock.

+ References

No definition available.

+ Details

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

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-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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Period Type:	duration

- Definition

Price of the entity's common stock which would be required to be attained for the conversion feature embedded in the debt instrument to become effective.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Number 210

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

+ References

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-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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Balance Type:	credit
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- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

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-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

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-Number 210

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-Paragraph 1

-Subparagraph (SX 210.12-29.6)

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Paragraph 15

-Subparagraph (b)

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-Glossary Financing Activities

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- Definition

Number of shares that have been repurchased and retired during the period.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Number 210

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Article 5

-Subsection 19, 20, 22

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Debt - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		12 Months Ended			0 Months Ended
Debt - Additional Information (Detail) (USD $)	Mar. 31, 2009	Mar. 30, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 13, 2014	Apr. 01, 2009
Debt Instrument
Borrowings from local bank	$ 10,000,000us-gaap_LoansPayableToBank
Term of loan, years	5 years
Debt instrument, interest rate, stated percentage	0.80%
Loan collateralized by real estate mortgage	6,000,000us-gaap_MortgageLoansOnRealEstate
Unsecured loan	4,000,000us-gaap_UnsecuredDebt
Semiannual principal payments of loan		1,000,000	1,000,000
Aggregate principal amount					189,998,000us-gaap_DebtInstrumentFaceAmount
Payments of long-term debt				190,972,000us-gaap_RepaymentsOfLongTermDebt	2,534,000us-gaap_RepaymentsOfLongTermDebt	2,533,000us-gaap_RepaymentsOfLongTermDebt
Common stock shares were issued for warrants exercised				21,200,000
Strike price per share of warrant				$ 7.6348
4.50% Convertible Senior Notes Due March 15, 2014
Debt Instrument
Debt instrument, interest rate, stated percentage	4.50%
Aggregate principal amount	175,000,000							190,000,000
Additional aggregate principal amount	1,000							15,000,000
Senior notes maturity date	Mar. 15, 2014							Mar. 15, 2014
Conversion rate in number of shares	182.65			131.95
Number of shares excluded for conversion rate calculation				50.7
Trading days used to determine average price per share				25 days
Average trading price of common shares				$ 19.74
Payments of long-term debt				$ 190,000,000
Stock issued in conversion of notes				25,100,000
Stock received and retired							25,100,000