XML 44 R64.htm IDEA: XBRL DOCUMENT v3.20.1
Selected Statement of Operations Data (Details Textual) - shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Employee Stock Option [Member]      
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]      
Anti-dilutive securities 32,000 334,200 354,000