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Equity-based Compensation and Equity Incentive Plans - Additional Information (Detail) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2021 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted average grant date fair value per share of options granted to employees |  | $ 2.42 | $ 1.27 |
Total fair value of awards vested |  | $ 2,800,000 | $ 3,400,000 |
Employee unrecognized compensation expense |  | $ 5,200,000 |  |
Employee unrecognized compensation cost, period of recognition |  | 2 years 7 months 6 days |  |
Equity-based compensation expense |  | $ 3,361,000 | 3,907,000 |
Restricted Common Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Total fair value of awards vested |  | 800,000 | $ 300,000 |
Employee unrecognized compensation expense |  | $ 700,000 |  |
Employee unrecognized compensation cost, period of recognition |  | 3 years |  |
Granted |  | 242,454 | 226,335 |
Equity-based compensation expense |  | $ 334,000 | $ 680,000 |
Common Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Issuance of common stock under employee stock purchase plan, Shares |  | 42,653 | 29,857 |
ESPP |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Increase in number of shares available for issuance (in shares) | 381,832 |  |  |
Percentage of discount for employees under ESPP |  | 15.00% |  |
Purchase price as a percentage of fair value under ESPP |  | 85.00% |  |
Equity-based compensation expense |  | $ 58,000 | $ 27,000 |
ESPP | Common Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Issuance of common stock under employee stock purchase plan, Shares |  | 42,653 |  |
Plan 2015 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Percentage of shares outstanding |  |  |  | 5.00%
Increase in number of shares available for issuance (in shares) | 1,909,163 |  |  |

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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount of cost to be recognized for option under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount of noncash expense for share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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- Definition Discount rate from fair value on offering date that participants pay for shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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