Aggregate offering price of securities.

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The percentage of gross proceeds on sales of stock that makes up the commission.

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The amount of upfront fee paid in cash.

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The amount of upfront payment in the form of shares.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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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.

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Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended					2 Months Ended	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Aug. 20, 2019	Jun. 30, 2022	Mar. 31, 2022	Feb. 28, 2022	Jun. 30, 2021	Feb. 28, 2021	Mar. 31, 2021	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Sale Of Stock [Line Items]
Common stock, shares authorized	100,000,000		100,000,000						100,000,000				100,000,000		100,000,000
Common stock, par value	$ 0.001		$ 0.001						$ 0.001				$ 0.001		$ 0.001
Preferred stock, shares authorized	5,000,000		5,000,000						5,000,000				5,000,000		5,000,000
Preferred stock, par value	$ 0.001		$ 0.001						$ 0.001				$ 0.001		$ 0.001
Common stock, shares outstanding	53,710,300		53,710,300						53,710,300				53,710,300		53,480,812
Common stock, shares issued	53,710,300		53,710,300						53,710,300				53,710,300		53,480,812
Preferred stock, shares issued	0		0						0				0		0
Preferred Stock Shares Outstanding	0		0						0				0		0
Non-Exclusive License Agreement \| Enteris Biopharma, Inc. [Member]
Sale Of Stock [Line Items]
Upfront fee payment, cash		$ 4,000
Upfront fee payment, stock		$ 4,000
Maximum [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities				$ 300,000						$ 300,000
Unsold Securities Under Shelf Registration Statement dated April 4, 2019 [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities				154,525						154,525
Open Market Sales Agreement [Member] \| Jeffries LLC [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities				$ 80,000						$ 80,000
Stock Sale Commission Percentage				3.00%
Common Stock
Sale Of Stock [Line Items]
Restricted stock units vested shares									89,075	109,943	36,000	109,419
Restricted Stock Units [Member] \| General and Administrative [Member]
Sale Of Stock [Line Items]
Compensation expense									$ 517		$ 206		$ 1,969	$ 1,027
Restricted Stock Units [Member] \| General and Administrative [Member] \| Director [Member]
Sale Of Stock [Line Items]
Compensation expense									$ 238		$ 142		$ 377	$ 281
Restricted Stock Units [Member] \| Common Stock \| Board of Directors Chairman [Member] \| June 2022 [Member]
Sale Of Stock [Line Items]
Restricted stock units vested shares			11,876
Restricted Stock Units [Member] \| Common Stock \| Director [Member] \| June 2022 [Member]
Sale Of Stock [Line Items]
Vesting period of awards granted			1 year
Restricted stock units, vested			43,200
Restricted Stock Units [Member] \| Common Stock \| Director [Member] \| June 2021 [Member]
Sale Of Stock [Line Items]
Vesting period of awards granted						1 year
Restricted stock units vested shares						36,000
Restricted Stock Units [Member] \| Common Stock \| Former Chief Executive Officer [Member] \| June 2022 [Member]
Sale Of Stock [Line Items]
Restricted stock units vested shares	33,999
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| March 2022 [Member]
Sale Of Stock [Line Items]
Vesting period of awards granted				3 years
Restricted stock units, vested				37,999
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February and March 2021 [Member]
Sale Of Stock [Line Items]
Restricted stock units vested shares								76,750
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| March 2022 [Member]
Sale Of Stock [Line Items]
Restricted stock units vested shares				39,278
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2022 [Member]
Sale Of Stock [Line Items]
Vesting period of awards granted					3 years
Restricted stock units vested shares					32,666
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2021 [Member]
Sale Of Stock [Line Items]
Vesting period of awards granted							3 years
Restricted stock units vested shares							32,669