Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Consolidated Balance Sheets
Preferred stock, par value (in dollars per share)	$ 5.00	$ 5.00
Preferred stock, authorized shares	500,000	500,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, authorized shares	15,000,000	15,000,000
Common stock, shares issued	6,563,440	6,541,049
Treasury stock, shares	989,300	935,368