Aggregate Offering Price of common stock.

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Class of warrant or right number of warrants issued.

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Class of warrant or right, term.

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Common stock average price.

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Common stock capital additional shares reserved for future issuance.

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Common stock value remained available to be sold.

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Maximum ownership percentage.

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Percentage of commission to be paid on gross sales proceeds of common stock sold.

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Prior notice period to increase or decrease maximum ownership percentage.

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Proceeds from issuance of common stock gross.

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Proceeds from issuance of common stock net.

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Share based compensation arrangement by share based payment award equity instruments options and restricted stock units outstanding.

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Shareholders ownership percent.

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Number of authorized capital units or capital shares. This element is relevant to issuers of face-amount certificates and registered investment companies.

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

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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Number of warrants or rights outstanding.

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Aggregate number of common shares reserved for future issuance.

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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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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.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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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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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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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Description of terms of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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Number of new stock issued during the period.

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Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	6 Months Ended
	Apr. 25, 2022	Nov. 30, 2021	Jun. 30, 2022	Dec. 31, 2021	Dec. 31, 2020	Nov. 30, 2020	Jun. 30, 2020	Jul. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Authorized capital stock			520,000,000
Common stock, par value			$ 0.0001	$ 0.0001
Common stock, shares authorized			500,000,000	500,000,000
Preferred stock, par value			$ 0.0001
Preferred stock, shares authorized			20,000,000
Preferred stock, shares outstanding			0	0
Stock option granted description terms			the exercise price of an option granted to a 10% shareholder cannot be less than 110% of the estimated fair value of the shares on the date of grant. Options granted generally vest over four years and expire in seven to ten years.
Ownership percent			10.00%
Shares of common stock, reserved for issuance			25,920,624
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock, reserved for issuance			19,762,888
Outstanding options and RSUs			15,589,015
Aggregate number of awards available for grant to be issued			4,173,873
Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock, reserved for issuance			5,367,281
Outstanding options and RSUs			3,742,764
Aggregate number of awards available for grant to be issued			1,624,517
Additional shares of common stock, reserved for issuance						1,500,000
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense			$ 87.9
Unrecognized stock-based compensation weighted average recognition period			3 years 1 month 6 days
Restricted Stock Units (RSUs) \| From Date Of Grant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation, vesting period			4 years
Employees And Non Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation, vesting period			4 years
Vested and Unvested Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation weighted average recognition period			2 years 9 months 18 days
Unrecognized stock-based compensation			$ 43.9
Maximum \| Employees And Non Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation award expiration period			10 years
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of employees purchase price of common stock			100.00%
Minimum \| 10% Shareholder
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of employees purchase price of common stock			110.00%
Minimum \| Employees And Non Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation award expiration period			7 years
Underwritten Public Offering \| 2019 Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding			2,888,526
Underwritten Public Offering \| Warrant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of warrants issued					2,040,816		2,866,961	2,945,026
Number of securities called by each warrant								1
Warrants, exercise price								$ 0.0001
Warrants, term	7 years
Maximum ownership Percentage	9.99%
Underwritten Public Offering \| Warrant \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum ownership Percentage	19.99%
Underwritten Public Offering \| Warrant \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Prior notice period	61 days
At The Market Offering \| Maximum \| Cowen
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock aggregate offering price		$ 100.0
Percentage of commission to be paid on gross sales proceeds of common stock sold		3.00%
2020 ATM Facility \| Cowen
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued			1,319,878
Common stock average price			$ 15.88
Proceeds from sale of common stock, gross			$ 21.0
Proceeds from sale of common stock, net			20.5
Common stock value remaining to be sold			$ 57.4