Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				3 Months Ended	9 Months Ended
	Jul. 31, 2020	May 31, 2020	Jan. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Common Stock, Shares Authorized					50,000,000	50,000,000		50,000,000
Common Stock, Par or Stated Value Per Share					$ 0.001	$ 0.001		$ 0.001
Common Stock, Shares, Outstanding					22,174,428	22,174,428		12,637,043
Common Stock, Shares, Issued					22,174,428	22,174,428		12,637,043
Proceeds from Issuance or Sale of Equity			$ 239,600
Net proceeds from issuance						$ 741,120	$ 185,687
Common Stock [Member]
Common Stock, Shares Authorized					50,000,000	50,000,000
Common Stock, Par or Stated Value Per Share					$ 0.001	$ 0.001
Common Stock, Shares, Outstanding					22,174,428	22,174,428
Common Stock, Shares, Issued					22,174,428	22,174,428
Number of shares sold	3,085,867	1,550,648	3,412,969
Stock Issued During Period Share Purchase Of Common Stock	402,504	202,259	445,170
Proceeds from Issuance or Sale of Equity	$ 248,200		$ 114,900
Common Stock [Member] | ATM Program [Member]
Number of shares sold					474,000	1,499,382
Net proceeds from issuance					$ 58,100	$ 138,400
Payments Of Stock Issuance Commissions					$ 1,200	$ 2,800
Amount of Shares Authorized				$ 250,000