Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Consolidated Balance Sheets
Common stock, Par value (in dollars per share)	$ 1.00	$ 1.00
Common Stock, Shares authorized	60,000,000	60,000,000
Common stock, Shares issued	34,625,734	34,534,234
Common stock, Shares outstanding	29,627,086	29,556,216
Treasury stock, Shares	4,998,648	4,978,018