Stock-Based Compensation - Summary of Stock Incentive Plans (Details) - $ / shares				1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 13, 2022	Jun. 16, 2020	May 12, 2015	Nov. 30, 2013	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Stock-based Compensation
Option outstanding					26,084	26,262
Options available for grant under stock option plans					4,303,288	626,342
Shares Available for Grant
Beginning balance (in shares)					626,342
Ending balance (in shares)					4,303,288	626,342
Stock Options Outstanding
Beginning balance (in shares)					26,262
Ending balance (in shares)					26,084	26,262
RSUs Outstanding
Beginning balance (in shares)					2,708,136
Ending balance (in shares)					2,702,070	2,708,136
Options vested, exercisable and expected to vest
Weighted average grant date fair value of stock options granted (in dollars per share)					$ 0	$ 0
Number of options vested (in shares)					271	1,524
Weighted average fair value of options vested on grant date					$ 336.43	$ 273.62
Stock options
Stock-based Compensation
Option outstanding					27,596	27,774	28,079
Stock Options Outstanding
Beginning balance (in shares)					27,774	28,079
Options exercised (in shares)					0		0
Options cancelled (in shares)					(178)	(305)
Ending balance (in shares)					27,596	27,774	28,079
Weighted Average Stock Option Exercise Price
Beginning balance (in dollars per share)					$ 596	$ 592.73
Options cancelled (in dollars per share)					362.34	327.81
Ending balance (in dollars per share)					$ 597	$ 596	$ 592.73
Weighted Average Remaining Contractual Life (Years)
Weighted Average Remaining Contractual Life (Years)					5 years 11 months 23 days	6 years 2 months 15 days	7 years 2 months 8 days
Options vested, exercisable and expected to vest
Options exercisable (in shares)					27,465
Options exercisable (in dollars per share)					$ 598.24
Options exercisable (in years)					5 years 11 months 19 days
Options vested and expected to vest (in shares)					27,594
Options vested and expected to vest (in dollars per share)					$ 597.16
Options vested and expected to vest (in years)					5 years 11 months 23 days
Options exercised (in shares)					0		0
Stock options and RSUs
Stock-based Compensation
Options available for grant under stock option plans					4,303,288	626,342	122,978
Shares Available for Grant
Beginning balance (in shares)					626,342	122,978
Additional shares authorized (in shares)					3,670,702	3,166,330
Options cancelled (in shares)					178	305
RSUs granted (in shares)						(2,690,320)
RSUs exercised					125
RSUs cancelled					5,941	5,241
RSUs vested and released (in shares)						21,808
Ending balance (in shares)					4,303,288	626,342	122,978
RSUs Outstanding
RSUs vested and released (in shares)						21,808
Restricted stock units issued and outstanding
Shares Available for Grant
RSUs vested and released (in shares)						(21,808)
RSUs Outstanding
Beginning balance (in shares)					2,708,136	44,865
RSUs Granted (in shares)						2,690,320
RSUs Exercised (in shares)					(125)
RSUs vested and released (in shares)						(21,808)
RSUs Cancelled (in shares)					(5,941)	(5,241)
Ending balance (in shares)					2,702,070	2,708,136	44,865
2013 Plan
Stock-based Compensation
Option shares outstanding					0	0
2013 Plan | Stock options
Stock Options Outstanding
Options granted (in shares)				0
2014 Plan
Stock-based Compensation
Incentive stock option term			10 years
Increase in share reserve based on outstanding number of shares (as a percent)			2.00%
Option outstanding					27,596	26,262
Options available for grant under stock option plans					4,302,288	626,342
Shares Available for Grant
Beginning balance (in shares)					626,342
Additional shares authorized (in shares)	2,417,660
Ending balance (in shares)					4,302,288	626,342
Stock Options Outstanding
Beginning balance (in shares)					26,262
Ending balance (in shares)					27,596	26,262
2020 Inducement Award Plan
Stock-based Compensation
Incentive stock option term		10 years
Options available for grant under stock option plans		2,222
Number of shares reserved for issuance	500,000
Shares Available for Grant
Ending balance (in shares)		2,222
2020 New Employee Inducement Award Plan
Stock-based Compensation
Option outstanding					1,512	1,512
Options available for grant under stock option plans					498,488	6,967
Number of shares reserved for issuance	971,833
Shares Available for Grant
Beginning balance (in shares)					6,967
Additional shares authorized (in shares)	471,833					498,448
Ending balance (in shares)					498,488	6,967
Stock Options Outstanding
Beginning balance (in shares)					1,512
Ending balance (in shares)					1,512	1,512
Common Stock
Options vested, exercisable and expected to vest
Share Price					$ 0.09
Participants Voting Power More than Ten Percent | 2014 Plan
Stock-based Compensation
Incentive stock option term			5 years
Participants Voting Power More than Ten Percent | 2020 Inducement Award Plan
Stock-based Compensation
Incentive stock option term		5 years