Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Feb. 24, 2021	Jan. 20, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 01, 2021	Mar. 31, 2020	May 10, 2019	Jan. 25, 2016
Subsidiary, Sale of Stock [Line Items]
Proceeds from shares sold			$ 878,850	$ 97,890	$ 100,060
Common stock, shares authorized (in shares)			600,000,000	600,000,000				600,000,000
Preferred stock, shares authorized (in shares)			2,000,000	2,000,000				2,000,000
Common stock, shares outstanding (in shares)			70,953,739	32,352,416
Sale of stock (in usd per share)									$ 111.20
Common Stock
Subsidiary, Sale of Stock [Line Items]
Shares sold (in shares)			32,393,438	12,980,177	2,941,438
Proceeds from shares sold			$ 324	$ 130	$ 29
January 2021 Sales Agreement
Subsidiary, Sale of Stock [Line Items]
Proceeds from shares sold			$ 835,600
January 2021 Sales Agreement | Common Stock
Subsidiary, Sale of Stock [Line Items]
Shares sold (in shares)			25,200,000
Proceeds from shares sold			$ 1,000,000
January 2021 Sales Agreement | Subsequent Event
Subsidiary, Sale of Stock [Line Items]
Shelf registration statement, maximum authorized common stock issuance						$ 3,200
January 2021 Sales Agreement | Subsequent Event | Common Stock
Subsidiary, Sale of Stock [Line Items]
Common stock issued upon exercise in full over-allotment granted (in shares)	1,700,000
January 2020 Sales Agreement
Subsidiary, Sale of Stock [Line Items]
Shares sold (in shares)			7,200,000
Proceeds from shares sold			$ 38,500
November 2020 Sales Agreement | Subsequent Event
Subsidiary, Sale of Stock [Line Items]
Shares sold (in shares)		900,000
Proceeds from shares sold		$ 113,000
November 2020 Sales Agreement | Subsequent Event | Common Stock
Subsidiary, Sale of Stock [Line Items]
Other stock issued during period		$ 27,200
March 2020 Sales Agreement
Subsidiary, Sale of Stock [Line Items]
Shelf registration statement, maximum authorized common stock issuance							$ 500
2019 Sales Agreements
Subsidiary, Sale of Stock [Line Items]
Shares sold (in shares)				13,000,000.0
2017 Sales Agreement
Subsidiary, Sale of Stock [Line Items]
Shares sold (in shares)					1,200,000
Proceeds from shares sold					$ 46,200
Public Offering
Subsidiary, Sale of Stock [Line Items]
Proceeds from shares sold					$ 54,000
Common stock issued upon exercise in full over-allotment granted (in shares)					200,000
Sale of stock (in usd per share)					$ 33.00
Payments of stock issuance costs					$ 3,600
Maximum
Subsidiary, Sale of Stock [Line Items]
Common stock, shares outstanding (in shares)								469,453,883
Minimum
Subsidiary, Sale of Stock [Line Items]
Common stock, shares outstanding (in shares)								23,472,574