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Nature of Business, Basis of Presentation and Significant Accounting Policies - Additional Information (Details) $ / shares in Units, $ in Millions |  |  |  |  | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2020 USD ($) $ / shares shares | Dec. 07, 2020 USD ($) | Jun. 14, 2019 USD ($) | May 08, 2019 shares | Oct. 31, 2020 USD ($) shares | Oct. 31, 2019 USD ($) shares | Oct. 31, 2018 USD ($) shares | Dec. 17, 2020 USD ($) | Dec. 17, 2020 CAD ($) | Dec. 04, 2020 shares | May 11, 2020 shares | Nov. 01, 2019 USD ($) | May 07, 2019 shares | Oct. 31, 2017 shares
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reverse stock split |  |  |  | 1-for-12 reverse stock split |  |  |  |  |  |  |  |  |  |
Reverse stock split, conversion ratio |  |  |  | 0.084 |  |  |  |  |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  |  | 15,284,269 | 294,706,758 | 193,608,684 |  |  |  |  |  |  | 183,411,230 |
Common stock, shares authorized | shares |  |  |  | 225,000,000 | 337,500,000 | 225,000,000 |  |  |  |  | 112,500,000 |  |  |
Preferred stock, shares authorized | shares |  |  |  | 250,000 |  | 250,000 |  |  |  |  |  |  |  |
Cash and cash equivalents, unrestricted |  |  |  |  | $ 149,867,000 | $ 9,434,000 |  |  |  |  |  |  |  |
Unrestricted cash |  |  |  |  | 47,500,000 |  |  |  |  |  |  |  |  |
Impairment charges |  |  |  |  | $ 0 | 0 | $ 0 |  |  |  |  |  |  |
Milestone-based payments |  |  | $ 10,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Project represented value of contract |  |  |  |  |  | 10,000,000.0 |  |  |  |  |  |  |  |
Extended Product Warranty Description |  |  |  |  | We warranty our products for a specific period of time against manufacturing or performance defects. Our U.S. warranty is generally limited to a term of 15 months after shipment or 12 months after acceptance of our products. |  |  |  |  |  |  |  |  |
Foreign Currency Transaction Gains (Losses), Net |  |  |  |  | $ 200,000 | $ (100,000) | $ 300,000 |  |  |  |  |  |  |
Operating lease liability |  |  |  |  | 10,756,000 |  |  |  |  |  |  | $ 10,100,000 |  |
Operating lease right-of-use assets, net |  |  |  |  | 10,098,000 |  |  |  |  |  |  | $ 10,300,000 |  |
ASC 842 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease liability |  |  |  |  | 10,300,000 |  |  |  |  |  |  |  |  |
Operating lease right-of-use assets, net |  |  |  |  | $ 10,100,000 |  |  |  |  |  |  |  |  |
Sales Revenue Net [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant customer revenue percentage |  |  |  |  | 86.00% | 81.00% | 88.00% |  |  |  |  |  |  |
Joint Development Agreement II [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from license fees received |  |  |  |  | $ 4,000,000.0 |  |  |  |  |  |  |  |  |
Specific Upgrades [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  | 0 | $ 0 |  |  |  |  |  |  |  |
Unspecific Upgrades [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  | $ 800,000 | $ 1,100,000 |  |  |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  |  |  | 294,706,758 | 193,608,684 | 7,972,686 |  |  |  |  |  |  | 5,791,068
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  |  |  |  |  |  |  |  | 319,706,758 |  |  |  |
Underwritten Offering Shares | $ / shares | $ 25,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from underwriting shares after deducting underwriting discounts and commissions | $ 156,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares reserved for issuance | shares | 5,185,674 |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares available for issuance | shares | 15,093,242 |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Enbridge Inc. [Member] | Series 1 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction, Due from (to) Related Party |  |  |  |  |  |  |  | $ 21,500,000 | $ 27.4 |  |  |  |  |
Subsequent Event [Member] | Sr. Secured Debt [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of outstanding principal payment and interest |  | $ 87,300,000 |  |  |  |  |  |  |  |  |  |  |  |
Unrestricted cash |  | $ 11,200,000 |  |  |  |  |  |  |  |  |  |  |  |

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