Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Common stock, par value	$ 2.00	$ 2.00
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	23,354,257	23,354,082
Common stock, shares outstanding	48,785	46,087