Warrants for Common Stock and Preferred and Common Units - Summary of warrants (Detail) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Class of Warrant or Right [Line Items]
Number of Shares of Common Stock Issuable	99,986	99,986
Common Stock [Member] \| August 14, 2015
Class of Warrant or Right [Line Items]
Contractual Term	10 years	10 years
Number of Shares of Common Stock Issuable	74,622	74,622
Exercise Price	$ 24.05	$ 24.05
Common Stock [Member] \| October 9, 2015
Class of Warrant or Right [Line Items]
Contractual Term	10 years	10 years
Number of Shares of Common Stock Issuable	7,798	7,798
Exercise Price	$ 24.05	$ 24.05
Common Stock [Member] \| June 14, 2018
Class of Warrant or Right [Line Items]
Contractual Term	10 years	10 years
Number of Shares of Common Stock Issuable	2,152	2,152
Exercise Price	$ 30.13	$ 30.13
Common Stock [Member] \| December 20, 2019
Class of Warrant or Right [Line Items]
Contractual Term	10 years	10 years
Number of Shares of Common Stock Issuable	15,414	15,414
Exercise Price	$ 18.98	$ 18.98

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

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

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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.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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