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Stockholders' Equity - Common stock (Details) - USD ($) |  |  |  |  | 3 Months Ended | 4 Months Ended | 9 Months Ended | 12 Months Ended | 13 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 09, 2022 | Aug. 02, 2022 | May 16, 2022 | Jan. 14, 2022 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2020 | Dec. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2023 | Aug. 18, 2023 | Aug. 17, 2022 | Jul. 14, 2022
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of common stock, net |  |  |  |  | $ 2,956,000 | $ 1,328,000 | $ 895,000 | $ 6,815,000 | $ 152,000 | $ 7,742,000 |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  | 100,000,000 |  |  |  |  |  | 100,000,000 | 100,000,000 | 100,000,000 |  |  | 100,000,000 |  | 100,000,000 |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,180,000 | $ 14,558,000 |  |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of common stock, net |  |  |  |  | $ 2,000 | $ 1,000 |  | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  | 1,589,655 | 472,674 | 168,164 | 673,421 | 18,070 | 445,840 |  |  |  |  |  |  |  |  |  |  |
2022 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  | 57,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2022 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum value of shares to be issued under agreement |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  |  |  | 266,666 |  | 410,500 |  |  |  |  |  |  |  |
Period exercisable from the date of issuance |  |  |  |  |  |  |  |  |  |  |  |  | 36 months |  |  |  |  |  |  |  |
Number of maximum common shares can be resale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 633,333 |
Initial commitment shares |  | 32,846 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 32,846
Initial commitment fee paid in cash |  | $ 125,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate gross proceeds from sales of common stock |  | $ 25,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  | $ 3,200,000 |  | $ 1,000,000 |  |  |  |  |  |  |  |
2022 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage issuance of common stock |  |  | 19.99% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2022 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of maximum common shares can be resale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,500,000 |  |
Number of shares reserved for issuance and sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 600,486 |
2020 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 377,666 | $ 379,012 |  |  |  |
Maximum value of shares to be issued under agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25,000,000.0 |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 527,166 |  |  |
Period exercisable from the date of issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 36 months |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,000,000 | $ 12,500,000 |  |  |  |
Remaining common stock issued and sold (in shares) |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  | 0 |  |  |  |  |
September 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | At The Market Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reimburse of fee and disbursements expenses | $ 50,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
September 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] | At The Market Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  |  |  |  | 68,758 | 1,819,993 |  |  |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  | $ 600,000 | $ 4,300,000 |  |  |  |  |  |  |  |
September 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] | Maximum [Member] | At The Market Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of common stock, net | $ 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of commission on gross proceeds from sale of common stock | 3.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
January 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 460,151 |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,800,000 |  |  |  |  |
January 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] | At The Market Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining availability under financing facility |  |  |  | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
January 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] | Maximum [Member] | At The Market Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  | $ 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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