Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2020	Dec. 31, 2019
Balance Sheets [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	165,400	162,600
Preferred stock, shares outstanding	165,400	162,600
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	650,000,000	650,000,000
Common stock, shares issued	174,498,918	174,418,615
Common stock, shares outstanding	174,498,918	174,418,615