Debt instrument capitalized non cash costs.

No definition available.

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

- Definition

Repayment of accrued interest.

+ References

No definition available.

+ Details

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Namespace Prefix:	atec_
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Balance Type:	credit
Period Type:	duration

- Definition

Repayment of outstanding principal.

+ References

No definition available.

+ Details

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Namespace Prefix:	atec_
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Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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Period Type:	duration

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Balance Type:	credit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- 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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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

+ Details

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- Details

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Debt - Squadron Medical Credit Agreement (Details) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Aug. 10, 2021	Dec. 16, 2020	Nov. 06, 2018	Dec. 31, 2021	Dec. 31, 2020
Line Of Credit Facility [Line Items]
Issuance of common stock				99,627,000	82,294,000
Gain (loss) on debt extinguishment				$ (7,434)	$ (7,612)
Number of warrants outstanding				20,184,000
Squadron Medical Term Loan
Line Of Credit Facility [Line Items]
Issuance of common stock		2,700,270
Common stock price per share		$ 11.11
Additional debt issuance costs		$ 3,800
New debt issuance costs		30,000
Gain (loss) on debt extinguishment			$ (6,100)	$ (11,700)
Debt instrument capitalized non-cash costs			$ 3,800
Repaid of outstanding principal	$ 45,000
Accrued interest	$ 200
Squadron Medical Term Loan \| Common Stock \| Participant Lender
Line Of Credit Facility [Line Items]
Number of warrants outstanding				6,759,530
Squadron Medical Term Loan \| Term Loan
Line Of Credit Facility [Line Items]
Additional line of credit		$ 15,000
Debt instrument, maturity date		Jun. 30, 2026
Secured debt agreement		$ 30,000