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Stockholders' Equity (DRSPP) (Details) - USD ($)	3 Months Ended	6 Months Ended	214 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Oct. 15, 2019
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	874,300,000	874,300,000	874,300,000	874,300,000
DRSPP
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					9,000,000.0
Shares of common stock authorized and available for issuance (in shares)	8,500,000	8,500,000	8,500,000
Common shares issued through DRSPP (in shares)	92,316	197,588	34,811,991
Net proceeds from shares issued through DRSPP	$ 406,807	$ 794,979	$ 288,400,000

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Aggregate number of common shares reserved for future issuance.

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