Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Common Stock, par value	$ 0.001	$ 0.001
Common Stock, shares authorized	300,000,000	200,000,000
Common Stock, shares issued	139,891,000	138,716,000
Common Stock, shares outstanding	139,891,000	138,716,000