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Common Stock - Issued and Outstanding Shares - Additional Information (Detail) - USD ($) |  |  |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended |
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May 27, 2021 | Dec. 07, 2020 | Aug. 06, 2020 | Jul. 01, 2020 | Apr. 28, 2020 | Mar. 12, 2020 | May 22, 2018 | Sep. 14, 2017 | Nov. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Aug. 03, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par value |  |  |  |  |  |  |  |  |  | $ 0.001 | $ 0.001 | $ 0.001 |  |
Common stock, shares issued |  |  |  |  |  |  |  |  |  | 17,897,029 | 17,897,029 | 9,453,542 |  |
Proceeds from exercise of warrants |  |  |  |  |  |  |  |  |  | $ 24,000 |  | $ 338,000 | $ 3,231,000 |
Stock option exercises, Shares |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  |
Restricted stock unit settlements |  |  |  |  |  |  |  |  |  | 26,625 |  | 231 |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  |  |  |  |  |  |  | 3,584 |  | 5,114 |  |
Restricted stock unit settlements |  |  |  |  |  |  |  |  |  | 26,625 |  | 145 | 128 |
November 2022 Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  |  | 280,782 |  |  |  |  |  |  |  |  |
Warrants to purchase shares of common stock |  |  |  |  | 0.75 |  |  |  |  |  |  |  |  |
Warrants to purchase shares of common stock, offering price per share |  |  |  |  | $ 6.60 |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  | $ 1,900,000 |  |  |  |  |  |  |  |  |
Proceeds from exercise of warrants |  |  |  |  | $ 1,600,000 |  |  |  |  |  |  |  |  |
Percentage of exercise price exceeds in measurement period |  |  |  |  | 300.00% |  |  |  |  |  |  |  |  |
Average daily trading volume for measurement period |  |  |  |  | $ 500,000 |  |  |  |  |  |  |  |  |
Number of required consecutive days weighted average trading price for cancelation or recall of warrants |  |  |  |  | 30 days |  |  |  |  |  |  |  |  |
November 2022 Private Placement [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  |  |  |  |  |  |  | 8,186,282 |  |  | 280,782 |
November 2022 Private Placement [Member] | Placement Agent [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per unit of warrant |  |  |  |  | $ 7.59 |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  | 25,270 |  |  |  |  |  |  |  |  |
July 2020 Registered Direct Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  | $ 6,000,000.0 |  |  |  |  |  |  |  |  |  |
Placement agent fees and offering expenses |  |  |  | 700,000 |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  |  | $ 5,300,000 |  |  |  |  |  |  |  |  |  |
July 2020 Registered Direct Offering [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  | 731,707 |  |  |  |  |  |  |  |  | 731,707 |
Common stock, price per share |  |  |  | $ 8.20 |  |  |  |  |  |  |  |  |  |
August 2020 Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  | $ 7,500,000 |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  | 6,800,000 |  |  |  |  |  |  |  |  |  | $ 6,822,000 |
Underwriting discounts and commissions and offering expenses |  |  | $ 700,000 |  |  |  |  |  |  |  |  |  |  |
August 2020 Public Offering [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  | 569,043 |  |  |  |  |  |  |  |  |  | 569,043 |
Common stock, price per share |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10.50
Underwriters Over-Allotment Option Exercise [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | 428,571 | 322,500 | 92,856 |  |  |  |  |  |  |  |  |  |  |
December 2020 Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,789,000 |
December 2020 Public Offering [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  | 2,472,500 |  |  |  |  |  |  |  |  |  |  | 2,472,500 |
Common stock, price per share |  | $ 7.00 |  |  |  |  |  |  |  |  |  |  |  |
December 2019 Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Offering expenses |  |  |  |  |  |  |  |  |  |  |  |  | $ 34,000 |
Gross proceeds from issuance of common stock |  | $ 17,300,000 |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  | 15,800,000 |  |  |  |  |  |  |  |  |  |  |  |
Underwriting discounts and commissions and offering expenses |  | $ 1,500,000 |  |  |  |  |  |  |  |  |  |  |  |
December 2019 Public Offering [Member] | Representative's Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  | 50,000 |  |  |  |  |  |  |  |  |  |  |  |
Common stock, price per share |  | $ 8.75 |  |  |  |  |  |  |  |  |  |  |  |
Adjustments to additional paid in capital |  | $ 300,000 |  |  |  |  |  |  |  |  |  |  |  |
Warrant exercisable term |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |
May 2021 Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock | $ 23,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock | 21,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Underwriting discounts and commissions and offering expenses | $ 1,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |
May 2021 Public Offering [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | 3,285,714 |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, price per share | $ 7.00 |  |  |  |  |  |  |  |  |  |  |  |  |
At-the-Market Sales Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  |  |  |  |  |  |  | 200,000 | 200,000 |  |  |
Gross proceeds |  |  |  |  |  |  |  |  |  | $ 1,500,000 | $ 1,500,000 |  |  |
Common stock aggregate maximum offering amount |  |  |  |  |  |  |  |  |  |  |  | $ 25,000,000 |  |
Common stock available for sale under offering |  |  |  |  |  |  |  |  |  | $ 23,500,000 | $ 23,500,000 |  |  |
Subscription Agreements Executed on April 27, 2020 [Member] | November 2022 Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per unit of warrant |  |  |  |  | $ 7.24 |  |  |  |  |  |  |  |  |
Subscription Agreements Executed on April 28, 2020 [Member] | November 2022 Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per unit of warrant |  |  |  |  | $ 7.32 |  |  |  |  |  |  |  |  |
Subscription Agreement Executed in November 2022 [Member] | November 2022 Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per unit of warrant |  |  |  |  |  |  |  |  | $ 4.50 |  |  |  |  |
Percentage of exercise price exceeds in measurement period |  |  |  |  |  |  |  |  | 300.00% |  |  |  |  |
Average daily trading volume for measurement period |  |  |  |  |  |  |  |  | $ 500,000 |  |  |  |  |
Number of required consecutive days weighted average trading price for cancelation or recall of warrants |  |  |  |  |  |  |  |  | 30 days |  |  |  |  |
Number of units issued in financing |  |  |  |  |  |  |  |  | 4,093,141 |  |  |  |  |
Common stock, price per unit |  |  |  |  |  |  |  |  | $ 4.625 |  |  |  |  |
Description of stock units issued |  |  |  |  |  |  |  |  |  | each unit consisting of two shares of common stock and a common stock purchase warrant to purchase one share of common stock, or the November 2022 Warrants |  |  |  |
Maximum beneficial ownership percentage of outstanding common stock for warrant holders |  |  |  |  |  |  |  |  | 19.99% |  |  |  |  |
Proceeds from financing |  |  |  |  |  |  |  |  | $ 17,900,000 |  |  |  |  |
Pre Funded Warrants | August 2020 Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  | 142,857 |  |  |  |  |  |  |  |  |  |  |
Pre-funded warrant, offering price per share |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.499
Pre Funded Warrants | August 2020 Public Offering [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per unit of warrant |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.001
Number of days of prior notice to achieve not in excess percentage of common stock shares owned by warrant holder |  |  | 61 days |  |  |  |  |  |  |  |  |  |  |
Pre Funded Warrants | August 2020 Public Offering [Member] | Common Stock [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of shares of common stock owned by warrant holder |  |  | 9.99% |  |  |  |  |  |  |  |  |  |  |
Pre Funded Warrants | August 2020 Public Offering [Member] | Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of shares of common stock owned by warrant holder |  |  | 19.99% |  |  |  |  |  |  |  |  |  |  |
LPC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock value right to sell, maximum |  |  |  |  |  | $ 11,000,000.0 |  |  |  |  |  |  |  |
Common stock, par value |  |  |  |  |  | $ 0.001 |  |  |  |  |  |  |  |
Minimum percentage of common stock shares outstanding authorized to sell |  |  |  |  |  |  | 20.00% |  |  |  |  |  |  |
Initial purchase of common stock |  |  |  |  |  |  |  | 1,644 |  |  |  |  |  |
Common stock, shares issued |  |  |  |  |  |  |  | 617 |  |  |  |  |  |
Payments related to expense reimbursement |  |  |  |  |  | $ 100,000 |  |  |  |  |  |  |  |
Common stock, shares issued |  |  |  |  |  |  |  | 27,868 |  | 0 |  |  |  |
Gross proceeds |  |  |  |  |  |  |  | $ 4,400,000 |  |  |  |  |  |
Offering expenses |  |  |  |  |  |  |  | $ 500,000 |  |  |  |  |  |
Purchase agreement expired date |  |  |  |  |  |  |  | Mar. 14, 2022 |  |  |  |  |  |
LPC [Member] | Purchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, purchase price |  |  |  |  |  |  |  | $ 1.00 |  |  |  |  |  |
Additional common stock value right to sell, maximum |  |  |  |  |  |  |  | $ 10,000,000.0 |  |  |  |  |  |
Additional purchase of common stock, maximum |  |  |  |  |  |  |  | 7,500 |  |  |  |  |  |
Offering expenses |  |  |  |  |  |  |  |  |  |  |  |  | $ 14,000 |
LPC [Member] | Units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial purchase of common stock |  |  |  |  |  |  |  | 1,644 |  |  |  |  |  |
Common stock, purchase price |  |  |  |  |  |  |  | $ 608 |  |  |  |  |  |
Purchase agreement, description |  |  |  |  |  |  |  |  |  | Unit consisting of (a) one share of our common stock and (b) one warrant to purchase one-quarter of a share of common stock at an exercise price of $699.20 per share, or LPC Warrant. Each LPC Warrant became exercisable six months following the issuance date until the date that is five years and six months after the issuance date and is subject to customary adjustments. |  |  |  |
Exercise price per unit of warrant |  |  |  |  |  |  |  | $ 699.20 |  |  |  |  |  |
Initial purchase of units consisting of common stock and warrants issued |  |  |  |  |  |  |  | $ 1,000,000.0 |  |  |  |  |  |
LPC [Member] | Other Units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of warrants issued |  |  |  |  |  |  |  | 0 |  |  |  |  |  |

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