Stockholders' Equity (DRSPP) (Details) - USD ($)	3 Months Ended	211 Months Ended
	Mar. 31, 2021	Mar. 31, 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
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)	8,600,000	8,600,000
Common shares issued through DRSPP (in shares)	105,272	34,719,675
Net proceeds from shares issued through DRSPP	$ 388,173	$ 288,000,000.0