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v3.22.2.2

Stockholders' Equity - Common stock (Details) - USD ($) |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |
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Sep. 09, 2022 | Aug. 02, 2022 | May 16, 2022 | Jan. 14, 2022 | Jun. 16, 2020 | Oct. 20, 2022 | Sep. 30, 2022 | Sep. 30, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2021 | Aug. 17, 2022 | Aug. 15, 2022 | Jul. 14, 2022 | Oct. 23, 2020
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of common stock, net |  |  |  |  |  |  |  |  | $ 6,815,000 | $ 152,000 | $ 7,742,000 | $ 6,354,000 | $ 5,094,000 | $ 7,078,000 |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  | 100,000,000 | 100,000,000 | 100,000,000 |  |  |  |  |  | 100,000,000 |  |  | 100,000,000 |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 14,558,000 | $ 18,665,000 |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of common stock, net |  |  |  |  |  |  |  |  | $ 10,000 |  | $ 6,000 | $ 3,000 | $ 2,000 | $ 2,000 |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  | 10,101,320 | 271,047 | 6,687,610 | 3,272,500 | 1,907,000 | 2,534,879 |  |  |  |  |  |  |  |
Number of stock repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |
Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Authorized amount of repurchase of stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,000,000.0 |  |
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 |  | $ 50,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  | 4,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Period exercisable from the date of issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 36 months |  |  |  |  |  |  |
Number of maximum common shares can be resale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,500,000 |  |  |
Initial commitment shares |  | 492,698 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 492,698 |
Initial commitment fee paid in cash |  | $ 125,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate gross proceeds from sales of common stock |  | $ 25,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  | $ 3,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
2022 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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 shares reserved for issuance and sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,007,302 |  |  |
2020 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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25,000,000.0 |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,665,000 |  |  | 5,685,186 |  |  |  |
Period exercisable from the date of issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 36 months |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,000,000.0 |  |  | $ 12,500,000 |  |  |  |
Remaining common stock issued and sold (in shares) |  |  |  |  |  |  | 0 | 0 | 0 |  |  |  |  |  | 0 |  |  |  |  |  |  |
2020 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% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Purchase Agreement [Member] | Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  | 23,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales 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
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) |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
September 2022 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] | At The Market Offering Program [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  | $ 600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,902,279 |  |  |  |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,500,000 |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Distribution Agreement [Member] | Canaccord Genuity LLC [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,179,193 |  |  |  |
Proceeds from sale of common stock, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,300,000 |  |  |  |

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