Select Balance Sheet Details - Accrued Expense (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Balance Sheet Related Disclosures [Abstract]
Legal	$ 572atec_AccruedLegalCurrent	$ 967atec_AccruedLegalCurrent
Accounting	856atec_AccruedAccountingCurrent	1,262atec_AccruedAccountingCurrent
Severance	114atec_AccruedSeverance	318atec_AccruedSeverance
Restructuring	336us-gaap_RestructuringReserve	531us-gaap_RestructuringReserve
Sales milestones	118atec_AccruedSalesMilestones	107atec_AccruedSalesMilestones
Accrued taxes	906us-gaap_AccruedIncomeTaxesCurrent	1,344us-gaap_AccruedIncomeTaxesCurrent
Deferred rent	681us-gaap_DeferredRentCreditCurrent	785us-gaap_DeferredRentCreditCurrent
Royalties	2,094	2,129
Commissions	4,390us-gaap_AccruedSalesCommissionCurrent	6,152us-gaap_AccruedSalesCommissionCurrent
Payroll and related	6,454	8,291
Litigation settlements	6,397us-gaap_LitigationReserveCurrent	7,393us-gaap_LitigationReserveCurrent
Accrued interest	997	946
Other	6,465us-gaap_OtherAccruedLiabilitiesCurrent	5,168us-gaap_OtherAccruedLiabilitiesCurrent
Total accrued expenses	$ 30,380us-gaap_AccruedLiabilitiesCurrent	$ 35,393us-gaap_AccruedLiabilitiesCurrent

Accrued Accounting, Current

No definition available.

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- Definition

Accrued Legal, Current

+ References

No definition available.

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- Definition

Accrued Sales Milestones

+ References

No definition available.

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- Definition

Accrued Severance

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.15(a))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph a

-Article 7

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6911-107765

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- Definition

For a classified balance sheet, the cumulative difference as of the balance sheet date between the payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, within one year of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 2

-Subparagraph (a)

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- Definition

Amount of accrued but unpaid interest on deposit liabilities.

+ References

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 25

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 55

-Paragraph 11

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Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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