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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended					3 Months Ended
	Nov. 27, 2019	Jan. 31, 2022	Jun. 30, 2021	Oct. 31, 2019	Dec. 31, 2018	Aug. 31, 2018	Mar. 31, 2022	Dec. 31, 2021	Aug. 06, 2018
Stock transactions
Par value (per share)							$ 0.00001	$ 0.00001
2019 Form S-3
Stock transactions
Common stock available for sale							$ 79.3
Maximum aggregate offering price				$ 250.0
2019 Sales Agreement
Stock transactions
Common stock issued (in shares)		422,367
Common stock available for sale							$ 17.0
Maximum aggregate offering price	$ 250.0			$ 75.0
Proceeds from public offering of common stock, net of issuance costs		$ 14.6
Underwritten public offering
Stock transactions
Net proceeds from sale of common stock			$ 123.8
Common stock issued (in shares)			3,046,358
Common stock issued, price per share			$ 37.75
underwritten public offering, Additional offering
Stock transactions
Common stock issued (in shares)			456,953
Common stock issued, price per share			$ 37.75
Common Stock
Stock transactions
Common stock issued (in shares)							422,367
Common Stock | Private Placement
Stock transactions
Number of warrants exercised							0
Investors | Private Placement
Stock transactions
Aggregate shares of common stock sold						2,750,000
Common stock sold, price per share						$ 8.00
Net proceeds from sale of common stock						$ 21.7
Warrants issued to purchase common stock, number of shares									2,750,000
Warrants exercisable date						Aug. 08, 2023
Exchange Agreement | Exchanging Stockholders
Stock transactions
Warrants issued to purchase common stock, number of shares					1,000,000
Exercise Price (per share)					$ 0.00001
Common stock exchanged for pre-funded warrants					1,000,000
Par value (per share)					$ 0.00001
Duration of warrants from date of issuance (in years)					10 years
Equity method investment, ownership percentage					9.99%
Exchange Agreement | Exchanging Stockholders | Common Stock
Stock transactions
Remaining number of Exchange Warrants unexercised							400,000
$10.00 per share | Investors | Private Placement
Stock transactions
Warrants to purchase common stock (in shares)									1,375,000
Exercise Price (per share)									$ 10.00
$15.00 per share | Investors | Private Placement
Stock transactions
Warrants to purchase common stock (in shares)									1,375,000
Exercise Price (per share)									$ 15.00

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