Stockholder's Equity - Warrants (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding (in shares)	2,051,033
Fair value of warrants	$ 4.5
Warrants granted (in shares)	0	0	0
Warrants exercised (in shares)	0	0	0
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of warrants (in dollars per share)	$ 2.38
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of warrants (in dollars per share)	$ 3.42

Class Of Warrant Or Right, Exercised

No definition available.

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- Definition

Class Of Warrant Or Right, Granted

+ References

No definition available.

+ Details

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

+ Details

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of warrants not settleable in cash classified as equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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