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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Per share increase in conversion price of convertible common stock. Excludes change due to standard antidilution provision.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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No definition available.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

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The price per share of the conversion feature embedded in the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Increase for accrued, but unpaid interest on the debt instrument for the period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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

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Description of debt redemption features under terms of the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The effective interest rate during the reporting period.

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cash inflow from a borrowing supported by a written promise to pay an obligation.

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Debt (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended				3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 02, 2020	Mar. 13, 2020	Nov. 12, 2019	Jul. 02, 2019	Apr. 30, 2020	Mar. 19, 2020	May 30, 2019	Sep. 19, 2018	Aug. 31, 2018	Jun. 28, 2019	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2019	Apr. 23, 2019	Jun. 30, 2016
Debt Instrument [Line Items]
Proceeds from advance notes									$ 900
Percentage of accrued interest									7.00%
Intrinsic value of this beneficial conversion feature												$ 143
Proceeds from convertible debt											$ 467	1,275
Advance Notes [Member]
Debt Instrument [Line Items]
Conversion price							$ 2.25
Issuance of common stock upon note conversions shares							435,924
2019 Bridge Notes [Member]
Debt Instrument [Line Items]
Term loan interest rate											7.00%
Debt instrument amount										$ 1,700
Proceeds from advance notes				$ 750
Interest expense debt											$ 66
2019 Bridge Notes [Member] \| Bona fide financing [Member]
Debt Instrument [Line Items]
Proceeds from advance notes					$ 10,000						3,000
2019 Bridge Notes [Member] \| November Bridge Notes [Member]
Debt Instrument [Line Items]
Interest rate			7.00%		7.00%
Debt instrument amount			$ 350		$ 350
Maturity Date			Dec. 31, 2020		Dec. 31, 2020
2019 Bridge Notes [Member] \| November Bridge Notes [Member] \| Cheval Holdings [Member]
Debt Instrument [Line Items]
Debt instrument amount			$ 250
2019 Bridge Notes [Member] \| Cameron Durrant [Member] \| November Bridge Notes [Member]
Debt Instrument [Line Items]
Debt instrument amount			$ 100
2019 Bridge Notes [Member] \| Cheval [Member] \| November Bridge Notes [Member]
Debt Instrument [Line Items]
Debt instrument amount					$ 100
2019 Bridge Notes [Member] \| Nomis Bay [Member] \| November Bridge Notes [Member]
Debt Instrument [Line Items]
Debt instrument amount					$ 250
2019 Bridge Notes [Member] \| Advance Notes [Member]
Debt Instrument [Line Items]
Proceeds from advance notes										950
2019 Bridge Notes [Member] \| Nomis Bay LTD [Member]
Debt Instrument [Line Items]
Debt instrument amount										750
2019 Bridge Notes [Member] \| Cameron Durrant [Member]
Debt Instrument [Line Items]
Debt instrument amount										750
2019 Bridge Notes [Member] \| Chief Executive Officer [Member]
Debt Instrument [Line Items]
Debt instrument amount										$ 200
2019 Bridge Notes [Member] \| Bona Fide Financing Transaction [Member]
Debt Instrument [Line Items]
Proceeds from advance notes											$ 3,000
2018 Convertible Notes Payable [Member] \| Advance Notes [Member]
Debt Instrument [Line Items]
Common stock conversion price											$ 2.25
Intrinsic value of this beneficial conversion feature											$ 1,800
Debt discount amortization											785
2018 Convertible Notes Payable [Member] \| Non Qualified Financing [Member]
Debt Instrument [Line Items]
Proceeds from convertible debt											$ 10,000
Conversion price											$ 2.25
Black Horse Capital LP [Member] \| Convertible Promissory Note [Member]
Debt Instrument [Line Items]
Term loan interest rate								7.00%
Debt instrument amount								$ 2,500
2019 Convertible Notes Payable [Member]
Debt Instrument [Line Items]
Accrued interest												100
Term loan interest rate											7.50%
Debt instrument amount														$ 1,300
Interest expense debt												219
Proceeds from convertible debt	$ 4,300
Issuance of common stock upon note conversions shares	2,397,915
2019 Convertible Notes Payable [Member] \| Cheval. Dr. Dale Chappell [Member]
Debt Instrument [Line Items]
Issuance of common stock upon note conversions shares	316,666
2019 Convertible Notes Payable [Member] \| Advance Notes [Member]
Debt Instrument [Line Items]
Common stock conversion price											$ 6.25
Intrinsic value of this beneficial conversion feature											$ 1,800
Debt discount amortization											785
2019 Convertible Notes Payable [Member] \| Non Qualified Financing [Member]
Debt Instrument [Line Items]
Proceeds from convertible debt											$ 10,000
Conversion price											$ 6.25
2020 Convertible Redeemable Notes [Member]
Debt Instrument [Line Items]
Notes payable to vendors						$ 518,333
Term loan interest rate						7.00%
Debt discount amortization											$ 52
Interest expense debt											$ 165
Debt instrument redemption description											The notes could be redeemed by the Company at any time before the 270th day following issuance, at a redemption price equal to the principal and accrued but unpaid interest on the notes to the date of redemption, plus a premium that increases on day 61 and day 121 from the issuance date. Accordingly, the notes were repaid in June 2020 with proceeds from the Private Placement, and the notes were extinguished.
Fair value of convertible notes											$ 0
2020 Convertible Redeemable Notes [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Maturity Date		Mar. 13, 2021
Debt issue discount		$ 33,000
2020 Convertible Redeemable Notes [Member] \| Tranche Two [Member]
Debt Instrument [Line Items]
Maturity Date						Mar. 19, 2021
Debt issue discount						$ 18,833
Notes Payable To Vendors [Member]
Debt Instrument [Line Items]
Interest rate															10.00%
Notes payable to vendors															$ 1,200
Accrued interest												300
Notes Payable To Vendors [Member] \| 2019 Bridge Notes [Member]
Debt Instrument [Line Items]
Accrued interest												1,100
Debt instrument amount													$ 500
Notes Payable To Vendors [Member] \| 2018 Convertible Notes Payable [Member]
Debt Instrument [Line Items]
Accrued interest												200
Interest expense debt												$ 817