Quarterly report pursuant to Section 13 or 15(d)

Condensed Consolidated Balance Sheets (Parenthetical)

v3.19.3
Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)
Sep. 30, 2019
Dec. 31, 2018
Assets    
Accounts receivable, allowance for doubtful accounts $ 14,900 $ 169,107
Property, plant and equipment, accumulated depreciation 62,918,812 57,288,233
Intangible assets, accumulated amortization $ 15,540,065 $ 12,925,888
Shareholders' Equity    
Common stock, par value (in dollars per share) $ 1 $ 1
Common stock, shares authorized (in shares) 24,000,000 24,000,000
Common stock, shares issued (in shares) 10,300,000 10,300,000
Common stock in treasury, at cost (in shares) 1,305,149 1,424,279