Stockholders' Equity - Common Stock and Warrants (Details) $ / shares in Units, $ in Thousands		1 Months Ended			2 Months Ended	3 Months Ended	12 Months Ended
	Apr. 13, 2020 USD ($)	Feb. 28, 2021 USD ($) $ / shares shares	Nov. 30, 2020 USD ($) $ / shares shares	Aug. 31, 2020 USD ($) $ / shares shares	Feb. 28, 2021 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) item $ / shares shares	Dec. 31, 2020 $ / shares shares	Dec. 31, 2017 shares
Stockholders' equity
Preferred stock, Shares authorized						5,000,000.0
Preferred stock, par value | $ / shares						$ 0.01
Net proceeds from shares of common stock sold | $			$ 927,300	$ 344,400		$ 3,587,825
Common Stock Shares, Outstanding						566,385,952	458,051,920
Common stock, par value (in dollars per share) | $ / shares						$ 0.01	$ 0.01
Number of votes per share | item						1
Common stock shares issued			43,700,000	35,276,250
Share price (in dollars per share) | $ / shares			$ 22.25	$ 10.25
Number of warrants exercised (in shares)						16,489,014
Proceeds from exercise of warrants, net of transaction costs | $						$ 15,445
Series A Junior Participating Cumulative Preferred Stock
Stockholders' equity
Preferred stock, par value | $ / shares						$ 0.01
Common Stock Shares, Outstanding						0
SK Holdings Co LTD
Stockholders' equity
Net proceeds from shares of common stock sold | $		$ 1,600,000
Common stock shares issued		54,966,188
Per share price of shares of common stock | $ / shares		$ 29.2893			$ 29.2893
At Market Issuance Sales Agreement
Stockholders' equity
Authorized amount | $	$ 75,000
Public Offerings
Stockholders' equity
Net proceeds from shares of common stock sold | $					$ 1,800,000
Common stock shares issued					32,200,000
Share price (in dollars per share) | $ / shares		$ 65.00			$ 65.00
Warrant Issued With Amazon And Walmart Stores Inc Transaction Agreement In 2017
Stockholders' equity
Number of warrants were vested and exercisable						68,380,913	68,380,913
Maximum | Warrant Issued With Amazon And Walmart Stores Inc Transaction Agreement In 2017
Stockholders' equity
Class of Warrant or Right Issued								110,573,392