Subsequent Events	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Events The Company has completed an evaluation of all subsequent events after the audited balance sheet date of December 31, 2021 through the filing date of this Annual Report on Form 10-K with the SEC, to ensure that these consolidated financial statements include appropriate disclosure of events both recognized in the consolidated financial statements as of December 31, 2021, and events which occurred subsequently but were not recognized in the consolidated financial statements. The Company has concluded that no subsequent events have occurred that require disclosure, except as disclosed within these consolidated financial statements and as described below. In January 2022 the Company announced the deprioritization of AVR-RD-01, its investigational gene therapy program for Fabry disease. This decision was made due to several factors, including new clinical data showing variable engraftment patterns from the five most recently dosed patients in the Company’s Phase 2 clinical trial of AVR-RD-01 for the treatment of Fabry disease, which the Company refers to as the FAB-GT clinical trial. The emergence of such new data would have significantly extended the program’s development timeline. That development, coupled with an increasingly challenging market and regulatory environment for Fabry disease, were among the primary factors leading to the Company’s deprioritization of its Fabry program. As a result of the deprioritization, the Company has stopped enrollment of its Phase 2 FAB-GT clinical trial and will focus on its other pipeline programs. In connection with the deprioritization of AVR-RD-01 noted above, in January, 2022, the Company approved changes to the Company’s organization as well as a broader operational cost reduction plan. As part of this plan, the Company approved a reduction in the Company’s workforce by approximately 23% across different areas and functions in the Company (the “Workforce Reduction”). The Workforce Reduction is expected to be substantially complete in the first quarter of 2022. Affected employees were offered separation benefits, including severance payments. The Company estimates that the severance and termination-related costs will total approximately $2.5 million in the aggregate and expects to record these charges in the first quarter of 2022. The Company expects that payments of these costs will be substantially complete through the end of the first quarter of 2022.

Subsequent Events

12 Months Ended

Dec. 31, 2019

14. Subsequent Events

The Company has completed an evaluation of all subsequent events after the audited balance sheet date of December 31, 2021 through the filing date of this Annual Report on Form 10-K with the SEC, to ensure that these consolidated financial statements include appropriate disclosure of events both recognized in the consolidated financial statements as of December 31, 2021, and events which occurred subsequently but were not recognized in the consolidated financial statements. The Company has concluded that no subsequent events have occurred that require disclosure, except as disclosed within these consolidated financial statements and as described below.

In January 2022 the Company announced the deprioritization of AVR-RD-01, its investigational gene therapy program for Fabry disease. This decision was made due to several factors, including new clinical data showing variable engraftment patterns from the five most recently dosed patients in the Company’s Phase 2 clinical trial of AVR-RD-01 for the treatment of Fabry disease, which the Company refers to as the FAB-GT clinical trial. The emergence of such new data would have significantly extended the program’s development timeline. That development, coupled with an increasingly challenging market and regulatory environment for Fabry disease, were among the primary factors leading to the Company’s deprioritization of its Fabry program. As a result of the deprioritization, the Company has stopped enrollment of its Phase 2 FAB-GT clinical trial and will focus on its other pipeline programs.

In connection with the deprioritization of AVR-RD-01 noted above, in January, 2022, the Company approved changes to the Company’s organization as well as a broader operational cost reduction plan. As part of this plan, the Company approved a reduction in the Company’s workforce by approximately 23% across different areas and functions in the Company (the “Workforce Reduction”). The Workforce Reduction is expected to be substantially complete in the first quarter of 2022.

Affected employees were offered separation benefits, including severance payments. The Company estimates that the severance and termination-related costs will total approximately $2.5 million in the aggregate and expects to record these charges in the first quarter of 2022. The Company expects that payments of these costs will be substantially complete through the end of the first quarter of 2022.