Stockholders' Equity (Details) $ / shares in Units, $ in Thousands				3 Months Ended			4 Months Ended	10 Months Ended
	Mar. 01, 2022 USD ($)	Feb. 25, 2021 USD ($)	Mar. 12, 2020 USD ($)	Mar. 31, 2022 USD ($) installment $ / shares shares	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($) shares	May 09, 2022 USD ($) shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) shares	Feb. 22, 2022 $ / shares	Jun. 04, 2020 shares	Feb. 28, 2014 shares
Class of Stock [Line Items]
Common stock, authorized (in shares)				350,000,000				350,000,000			175,000,000
Common stock, par value (in dollars per share) | $ / shares				$ 0.00001				$ 0.00001		$ 0.00001
Common stock, issued (in shares)				183,386,035				177,000,963
Common stock, outstanding (in shares)				183,386,035				177,000,963
Preferred stock, shares authorized (in shares)				25,000,000				25,000,000
Preferred stock, par value (in dollars per share) | $ / shares				$ 0.00001				$ 0.00001
Preferred stock, issued (in shares)				0				0
Preferred stock, outstanding (in shares)				0				0
Proceeds from the issuance of common stock, net of issuance costs | $				$ 7,178		$ 29,327
Inducement Award Program
Class of Stock [Line Items]
Number of shares granted				279,000
Number of shares outstanding				279,000
Share-based Payment Arrangement, Option
Class of Stock [Line Items]
Expiration period				10 years
Share-based Payment Arrangement, Option | Share-based Compensation Award, Tranche, First Anniversary of Grant Date
Class of Stock [Line Items]
Vesting percentage				100.00%
Share-based Payment Arrangement, Option | Share Based Compensation Award Tranche One
Class of Stock [Line Items]
Vesting period				1 year
Vesting percentage				25.00%
Share-based Payment Arrangement, Option | Share Based Compensation Award Tranche Two
Class of Stock [Line Items]
Vesting period				1 year
Number of equal quarterly installments | installment				12
Service-Based Restricted Stock Units | Share Based Compensation Award Tranche One
Class of Stock [Line Items]
Vesting period				1 year
Vesting percentage				50.00%
Service-Based Restricted Stock Units | Share Based Compensation Award Tranche Two
Class of Stock [Line Items]
Vesting period				6 months
Vesting percentage				25.00%
Award vesting grace period				1 year
Service-Based Restricted Stock Units | Share-based Compensation Award, Tranche, First Or Third Anniversary of Grant Date
Class of Stock [Line Items]
Vesting percentage				100.00%
Service-Based Restricted Stock Units | Share-Based Payment Arrangement, Tranche One, First Anniversary After Grant Date, Subjected To Individual Continued Service
Class of Stock [Line Items]
Vesting period				1 year
Vesting percentage				33.33%
Service-Based Restricted Stock Units | Share-Based Payment Arrangement, Tranche Two, Second Anniversary After Grant Date, Subjected To Individual Continued Service
Class of Stock [Line Items]
Vesting period				2 years
Vesting percentage				33.33%
Service-Based Restricted Stock Units | Share-Based Payment Arrangement, Tranche Three, Third Anniversary After Grant Date, Subjected To Individual Continued Service
Class of Stock [Line Items]
Vesting period				3 years
Vesting percentage				33.33%
Common Stock
Class of Stock [Line Items]
Common stock, outstanding (in shares)				183,386,035		158,520,089		177,000,963	148,074,085
Issuance of common stock, net of issuance costs (in shares)				4,404,600		9,228,017
Common Stock | At The Market Equity Offering Program Authorized February 2021
Class of Stock [Line Items]
Issuance of common stock, net of issuance costs (in shares)								21,128,065
Proceeds from the issuance of common stock, net of issuance costs | $								$ 72,400
Common Stock | At The Market Equity Offering Program Authorized March 2022 | Subsequent Event
Class of Stock [Line Items]
Issuance of common stock, net of issuance costs (in shares)							404,600
Proceeds from the issuance of common stock, net of issuance costs | $							$ 800
Minimum | Share-based Payment Arrangement, Option
Class of Stock [Line Items]
Vesting period				12 months
Minimum | Service-Based Restricted Stock Units | Share-based Compensation Award, Tranche, First Or Third Anniversary of Grant Date
Class of Stock [Line Items]
Vesting period				1 year
Maximum | At The Market Equity Offering Program Authorized February 2021
Class of Stock [Line Items]
Common stock sales agreement amount | $		$ 100,000
Maximum | At The Market Equity Offering Program Authorized March 2022
Class of Stock [Line Items]
Common stock sales agreement amount | $	$ 25,300
Maximum | Share-based Payment Arrangement, Option
Class of Stock [Line Items]
Vesting period				48 months
Maximum | Service-Based Restricted Stock Units | Share-based Compensation Award, Tranche, First Or Third Anniversary of Grant Date
Class of Stock [Line Items]
Vesting period				3 years
At The Market Equity Offering Program | Common Stock
Class of Stock [Line Items]
Issuance of common stock, net of issuance costs (in shares)						5,224,278			3,509,381
Proceeds from the issuance of common stock, net of issuance costs | $					$ 15,900				$ 10,600
At The Market Equity Offering Program | Maximum
Class of Stock [Line Items]
Common stock sales agreement amount | $			$ 65,000
2014 Plans
Class of Stock [Line Items]
Common stock, reserved for future issuance (in shares)												1,785,000
Incremental rate at which the shares reserved for issuance increase				3.00%
2014 Plans | Share-based Payment Arrangement, Option | Employees
Class of Stock [Line Items]
Number of shares granted				2,833,500
2014 Plans | Performance Shares
Class of Stock [Line Items]
Number of shares granted				0
2014 Plans | Service-Based Restricted Stock Units | Employees
Class of Stock [Line Items]
Number of shares granted (in shares)				2,914,308
2014 Plans | Performance-Based Restricted Stock Units
Class of Stock [Line Items]
Number of shares granted (in shares)				0
2014 Employee Stock Purchase Plan
Class of Stock [Line Items]
Common stock, reserved for future issuance (in shares)				4,981,995
Offering period				6 months
Purchase price at the end of offering period				85.00%
Number of shares issued				191,146