Statements of Stockholders' Equity (Unaudited) (Parenthetical) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Stockholders' Equity [Abstract]
Exercise of stock options, net of cashless exercise of shares	82,161		93,570	21,864