Litigation Settlement, Number of Quarterly Installments

No definition available.

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Namespace Prefix:	atec_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Note receivable from shareholders for settlement payment.

+ References

No definition available.

+ Details

Name:	atec_NoteReceivableFromShareholdersForSettlementPayment
Namespace Prefix:	atec_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amounts due from owners or owners with a beneficial interest of more than 10 percent of the voting interests or officers of the company, which are usually due within 1 year (or 1 business cycle).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39599-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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

- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585

+ Details

Name:	us-gaap_PaymentsForLegalSettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Details

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- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=atec_OrthotecLLCLitigationSettlementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=atec_HealthpointCapitalMember
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Related Party Transactions - Additional Information (Details) $ in Thousands				1 Months Ended				9 Months Ended
	Oct. 01, 2020 USD ($)	Jul. 01, 2016 USD ($)	Aug. 13, 2014 USD ($) installment	Oct. 31, 2020 USD ($) installment	Sep. 30, 2014 USD ($)	Apr. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Sep. 30, 2020 USD ($) installment	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Settlement amount to be contributed								$ 5,000	$ 5,000
Withholding tax receivable from officer								934
Restricted Stock Units
Related Party Transaction [Line Items]
Withholding tax receivable from officer								900
Subsequent Event \| Restricted Stock Units
Related Party Transaction [Line Items]
Payment was remitted to settle the tax liability	$ 600
Orthotec LLC, litigation settlement
Related Party Transaction [Line Items]
Payments of settlement						$ 15,750	$ 1,750	$ 43,900
Judgment assessed by court for (against) company			$ (49,000)
Number of quarterly installments \| installment			28					5
Orthotec LLC, litigation settlement \| HealthpointCapital, LLC
Related Party Transaction [Line Items]
Payments of settlement		$ 1,000						$ 1,100
Judgment assessed by court for (against) company					$ (5,000)
Settlement amount to be contributed								$ 5,000
Orthotec LLC, litigation settlement \| Subsequent Event \| HealthpointCapital, LLC
Related Party Transaction [Line Items]
Judgment assessed by court for (against) company				$ (5,000)
Number of quarterly installments \| installment				5