Aggregate offering price of securities.

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- Definition

The number of votes that each common stock receives.

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- Definition

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

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Face amount or stated value per share of common stock.

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- Definition

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

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- Definition

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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- Definition

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

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- Definition

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

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- Definition

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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- Definition

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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- Definition

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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- Definition

The cash inflow from the additional capital contribution to the entity.

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- Definition

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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- Definition

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

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- Definition

Number of new stock issued during the period.

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- Definition

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

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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.

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No definition available.

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Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands			1 Months Ended																		2 Months Ended	12 Months Ended
	Dec. 17, 2021	Jun. 04, 2020	Oct. 31, 2023 shares	Aug. 31, 2023 shares	Jul. 31, 2023 shares	Jun. 30, 2023 shares	Apr. 30, 2023 shares	Mar. 31, 2023 shares	Feb. 28, 2023 shares	Jan. 31, 2023 shares	Dec. 31, 2022 $ / shares shares	Oct. 31, 2022 shares	Sep. 30, 2022 shares	Jun. 30, 2022 shares	Mar. 31, 2022 USD ($) shares	Feb. 28, 2022 shares	Oct. 31, 2021 shares	Aug. 31, 2021 shares	Jun. 30, 2021 shares	Feb. 28, 2021 shares	Mar. 31, 2021 shares	Dec. 31, 2023 USD ($) item $ / shares shares	Dec. 31, 2022 $ / shares shares	Dec. 31, 2021 shares
Sale Of Stock [Line Items]
Common stock, shares authorized											100,000,000											100,000,000	100,000,000
Common stock, par value \| $ / shares											$ 0.001											$ 0.001	$ 0.001
Preferred stock, shares authorized											5,000,000											5,000,000	5,000,000
Preferred stock, par value \| $ / shares											$ 0.001											$ 0.001	$ 0.001
Common stock, shares issued											53,797,341											54,480,704	53,797,341
Common stock, shares outstanding											53,797,341											54,480,704	53,797,341
Preferred stock, shares issued											0											0	0
Preferred stock, shares outstanding											0											0	0
Number of votes for each share of common stock \| item																						1
Proceeds from the sale of common stock \| $																						$ 1,117
Regulatory Milestones [Member] \| Vifor International Ltd. [Member]
Sale Of Stock [Line Items]
Common stock, shares issued																	3,282,391
Unsold Securities Under Shelf Registration Statement dated April 4, 2019 [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities \| $															$ 154,525
Open Market Sales Agreement [Member] \| Jeffries LLC [Member]
Sale Of Stock [Line Items]
Stock Sale Commission Percentage															3.00%
Common stock, shares issued																						386,881
Proceeds from the sale of common stock \| $																						$ 1,117
Open Market Sales Agreement [Member] \| Jeffries LLC [Member] \| Maximum [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities \| $															$ 80,000
2022 Shelf Registration Statement [Member] \| Maximum [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities \| $															$ 300,000
Common Stock
Sale Of Stock [Line Items]
Restricted stock units vested shares																						203,264	268,222	189,421
Common stock, shares issued																						386,881
Restricted Stock Units [Member] \| 2014 Equity Incentive Plan [Member] \| Director [Member] \| June 2020
Sale Of Stock [Line Items]
Vesting period of awards granted		1 year
Restricted Stock Units [Member] \| Common Stock \| Board of Directors Chairman [Member] \| June 2022
Sale Of Stock [Line Items]
Restricted stock units vested shares														11,876
Restricted Stock Units [Member] \| Common Stock \| Director [Member] \| June 2022
Sale Of Stock [Line Items]
Restricted stock units, vested														43,200
Vesting period of awards granted														1 year
Restricted Stock Units [Member] \| Common Stock \| Director [Member] \| June 2021
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
Sale Of Stock [Line Items]
Restricted stock units vested shares														33,999
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| December 2022
Sale Of Stock [Line Items]
Restricted stock units, vested											26,204
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| March 2022
Sale Of Stock [Line Items]
Restricted stock units, vested															37,999
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| August 2021
Sale Of Stock [Line Items]
Restricted stock units, vested																		44,002
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February and March 2021
Sale Of Stock [Line Items]
Restricted stock units vested shares																					76,750
Time-based Restricted Stock Units [Member] \| 2014 Equity Incentive Plan [Member] \| Executive Officers [Member] \| December 2021
Sale Of Stock [Line Items]
Restricted stock units, vested											26,204											0
Vesting period of awards granted	18 months
Time-based Restricted Stock Units [Member] \| 2014 Equity Incentive Plan [Member] \| Executive Officers [Member] \| March 2021
Sale Of Stock [Line Items]
Restricted stock units, vested								15,999
Time-based Restricted Stock Units [Member] \| 2014 Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| October 2021
Sale Of Stock [Line Items]
Restricted stock units, vested												35,500										35,500
Time-based Restricted Stock Units [Member] \| 2014 Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| October 2022
Sale Of Stock [Line Items]
Restricted stock units, vested												35,500
Time-based Restricted Stock Units [Member] \| Common Stock \| Director [Member] \| June 2022
Sale Of Stock [Line Items]
Restricted stock units, vested						59,380
Vesting period of awards granted						1 year
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2022
Sale Of Stock [Line Items]
Restricted stock units, vested									42,920
Vesting period of awards granted									3 years							3 years
Restricted stock units vested shares																32,666
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| March 2022
Sale Of Stock [Line Items]
Vesting period of awards granted															3 years
Restricted stock units vested shares															39,278
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2021
Sale Of Stock [Line Items]
Vesting period of awards granted																				3 years
Restricted stock units vested shares																				32,669
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2020
Sale Of Stock [Line Items]
Restricted stock units, vested									15,999
Vesting period of awards granted									3 years
Time-based Restricted Stock Units [Member] \| Common Stock \| Interim Principal Financial and Accounting Officer [Member] \| September 2022
Sale Of Stock [Line Items]
Restricted stock units, vested													7,500
Time-based Restricted Stock Units [Member] \| Common Stock \| Chief Executive Officer [Member] \| October 2021
Sale Of Stock [Line Items]
Restricted stock units, vested			8,875		8,875		8,875			8,875
Time-based Restricted Stock Units [Member] \| Common Stock \| Chief Executive Officer [Member] \| October 2022
Sale Of Stock [Line Items]
Restricted stock units, vested				7,267
Time-based Restricted Stock Units [Member] \| Common Stock \| Chief Executive Officer [Member] \| December 2021
Sale Of Stock [Line Items]
Restricted stock units, vested						26,199
Time-based Restricted Stock Units [Member] \| Common Stock \| Chief Executive Officer [Member] \| March 2021
Sale Of Stock [Line Items]
Restricted stock units, vested								15,999
Vesting period of awards granted								3 years