Subsequent Event	3 Months Ended
Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Event	14. Subsequent Event Salary-to-Equity Conversion Program Effective April 5, 2020, the Company implemented a voluntary salary-to-equity conversion program for certain employees whose annual payroll costs exceed $100,000, including the Company’s executive officers. The program permits each participant to make a voluntary election to reduce the participant’s compensation rate through July 11, 2020 from 10% to 75%. In exchange for the compensation reduction, each participant will be granted a restricted stock unit equal to the dollar amount of compensation reduction divided by the 30-day volume weighted average price of the Company’s common stock as of close of market on April 3, 2020. The restricted stock units granted under the program will fully vest on July 10, 2020. The restricted stock units will also vest upon a change in control of the Company and will be subject to certain accelerated vesting in the event of the participant’s death or disability. The temporary reduction in compensation to the participants shall not be treated as a reduction in base annual salary rate for purposes of any other benefits plans in which the participants are enrolled or eligible to participate, including in any bonus plans of the Company. Paycheck Protection Program Loan On April 23, 2020, the Company received the proceeds from a loan in the amount of approximately $4.3 million (the “PPP Loan”) from Silicon Valley Bank, as lender, pursuant to the Paycheck Protection Program (“PPP”) of the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”). The PPP Loan matures on April 21, 2022 and bears interest at a rate of 1.0% per annum. Commencing November 21, 2020, the Company is required to pay the lender equal monthly payments of principal and interest as required to fully amortize by April 21, 2022 the principal amount outstanding on the PPP Loan as of October 21, 2020. The PPP Loan is evidenced by a promissory note dated April 21, 2020, which contains customary events of default relating to, among other things, payment defaults and breaches of representations and warranties. The PPP Loan may be prepaid by the Company at any time prior to maturity with no prepayment penalties. All or a portion of the PPP Loan may be forgiven by the U.S. Small Business Administration (“SBA”) upon application by the Company beginning 60 days but not later than 120 days after loan approval and upon documentation of expenditures in accordance with the SBA requirements. Under the CARES Act, loan forgiveness is available for the sum of documented payroll costs, covered rent payments, covered mortgage interest and covered utilities during the eight-week period beginning on the date of loan approval. For purposes of the CARES Act, payroll costs exclude compensation of an individual employee in excess of $100,000, prorated annually. Not more than 25% of the forgiven amount may be for non-payroll costs. Forgiveness is reduced if full-time headcount declines, or if salaries and wages for employees with salaries of $100,000 or less annually are reduced by more than 25%. In the event the PPP Loan, or any portion thereof, is forgiven pursuant to the PPP, the amount forgiven is applied to outstanding principal. No assurance is provided that the Company will apply for and obtain forgiveness of the PPP Loan in whole or in part. The Company intends to use all proceeds from the PPP Loan to retain employees and maintain payroll. Termination of Tender Offer Agreement and Commitment Letter On April 27, 2020, the Company announced that it has terminated the Tender Offer Agreement with EOS Imaging S.A., or EOS. This decision follows the Company’s consideration and analysis of the expected ongoing market effects of the COVID-19 pandemic, including the magnitude and duration of its impact on capital equipment priorities and purchases in significant EOS markets, including the United States. Based upon its assessment, the Company concluded that a “Material Adverse Effect” (as defined in the Tender Offer Agreement) has occurred, resulting in circumstances that are no longer conducive to completion of the transaction described in the Tender Offer Agreement. The Company notified EOS of its termination decision, as required by the Tender Offer Agreement, in a letter dated April 24, 2020. On April 27, 2020, the Company also announced that, in connection with the termination of the Tender Offer Agreement, the Company and Perceptive Credit Holdings III, LP have agreed to terminate the debt refinancing commitment letter, including the exclusivity obligations thereunder, entered into in connection with the EOS transaction. Expanded Credit Facility With Squadron Capital On May 9, 2020, the Company executed a commitment letter for $35 million in additional secured financing from Squadron. This capital will be made available under the same material terms and conditions as the existing term loan with Squadron, subject to customary closing conditions. Under the terms of the amended facility, the maturity date on the entire term loan will be extended to May 2025. A portion of the proceeds from the expanded facility will be used to retire the Company’s outstanding obligation under its working capital revolver with MidCap. In connection with the additional commitment, the Company will issue warrants to purchase 1.076 million shares of ATEC common stock at an exercise price of $4.88 per share. ATEC expects this transaction to close before the end of May 2020.

Subsequent Event

3 Months Ended

Mar. 31, 2020

14. Subsequent Event

Salary-to-Equity Conversion Program

Effective April 5, 2020, the Company implemented a voluntary salary-to-equity conversion program for certain employees whose annual payroll costs exceed $100,000, including the Company’s executive officers. The program permits each participant to make a voluntary election to reduce the participant’s compensation rate through July 11, 2020 from 10% to 75%. In exchange for the compensation reduction, each participant will be granted a restricted stock unit equal to the dollar amount of compensation reduction divided by the 30-day volume weighted average price of the Company’s common stock as of close of market on April 3, 2020. The restricted stock units granted under the program will fully vest on July 10, 2020. The restricted stock units will also vest upon a change in control of the Company and will be subject to certain accelerated vesting in the event of the participant’s death or disability. The temporary reduction in compensation to the participants shall not be treated as a reduction in base annual salary rate for purposes of any other benefits plans in which the participants are enrolled or eligible to participate, including in any bonus plans of the Company.

Paycheck Protection Program Loan

On April 23, 2020, the Company received the proceeds from a loan in the amount of approximately $4.3 million (the “PPP Loan”) from Silicon Valley Bank, as lender, pursuant to the Paycheck Protection Program (“PPP”) of the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”). The PPP Loan matures on April 21, 2022 and bears interest at a rate of 1.0% per annum. Commencing November 21, 2020, the Company is required to pay the lender equal monthly payments of principal and interest as required to fully amortize by April 21, 2022 the principal amount outstanding on the PPP Loan as of October 21, 2020. The PPP Loan is evidenced by a promissory note dated April 21, 2020, which contains customary events of default relating to, among other things, payment defaults and breaches of representations and warranties. The PPP Loan may be prepaid by the Company at any time prior to maturity with no prepayment penalties.

All or a portion of the PPP Loan may be forgiven by the U.S. Small Business Administration (“SBA”) upon application by the Company beginning 60 days but not later than 120 days after loan approval and upon documentation of expenditures in accordance with the SBA requirements. Under the CARES Act, loan forgiveness is available for the sum of documented payroll costs, covered rent payments, covered mortgage interest and covered utilities during the eight-week period beginning on the date of loan approval. For purposes of the CARES Act, payroll costs exclude compensation of an individual employee in excess of $100,000, prorated annually. Not more than 25% of the forgiven amount may be for non-payroll costs. Forgiveness is reduced if full-time headcount declines, or if salaries and wages for employees with salaries of $100,000 or less annually are reduced by more than 25%. In the event the PPP Loan, or any portion thereof, is forgiven pursuant to the PPP, the amount forgiven is applied to outstanding principal. No assurance is provided that the Company will apply for and obtain forgiveness of the PPP Loan in whole or in part.

The Company intends to use all proceeds from the PPP Loan to retain employees and maintain payroll.

Termination of Tender Offer Agreement and Commitment Letter

On April 27, 2020, the Company announced that it has terminated the Tender Offer Agreement with EOS Imaging S.A., or EOS. This decision follows the Company’s consideration and analysis of the expected ongoing market effects of the COVID-19 pandemic, including the magnitude and duration of its impact on capital equipment priorities and purchases in significant EOS markets, including the United States. Based upon its assessment, the Company concluded that a “Material Adverse Effect” (as defined in the Tender Offer Agreement) has occurred, resulting in circumstances that are no longer conducive to completion of the transaction described in the Tender Offer Agreement. The Company notified EOS of its termination decision, as required by the Tender Offer Agreement, in a letter dated April 24, 2020.

On April 27, 2020, the Company also announced that, in connection with the termination of the Tender Offer Agreement, the Company and Perceptive Credit Holdings III, LP have agreed to terminate the debt refinancing commitment letter, including the exclusivity obligations thereunder, entered into in connection with the EOS transaction.

Expanded Credit Facility With Squadron Capital

On May 9, 2020, the Company executed a commitment letter for $35 million in additional secured financing from Squadron. This capital will be made available under the same material terms and conditions as the existing term loan with Squadron, subject to customary closing conditions. Under the terms of the amended facility, the maturity date on the entire term loan will be extended to May 2025. A portion of the proceeds from the expanded facility will be used to retire the Company’s outstanding obligation under its working capital revolver with MidCap. In connection with the additional commitment, the Company will issue warrants to purchase 1.076 million shares of ATEC common stock at an exercise price of $4.88 per share. ATEC expects this transaction to close before the end of May 2020.