Stockholders' Equity (Common Stock Reserved for Future Issuance) (Details) shares in Thousands	Sep. 30, 2022 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock options outstanding (in shares)	1,386
Total common shares reserved for future issuance (in shares)	13,884
Common stock available for future grant under the 2019 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for future grant (in shares)	365
Common stock available for future grant under the 2021 Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for future grant (in shares)	160
2022 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for future grant (in shares)	129
RSUs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs outstanding (in shares)	85
2019 PIPE Initial Closing warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding (in shares)	1,278
2019 PIPE Milestone Closing warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding (in shares)	3,059
2020 PIPE warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding (in shares)	1,849
Class A-1 convertible preferred stock outstanding (as-converted)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares outstanding (in shares)	257
Class A-2 convertible preferred stock outstanding (as-converted)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares outstanding (in shares)	1,331
Class A-3 convertible preferred stock outstanding (as-converted)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares outstanding (in shares)	259
Class A-4 convertible preferred stock outstanding (as-converted)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares outstanding (in shares)	3,726

Number of warrants or rights outstanding.

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Aggregate number of common shares reserved for future issuance.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Number of options outstanding, including both vested and non-vested options.

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