Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Consolidated Balance Sheets [Abstract]
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	12,000,000	12,000,000
Common stock, shares issued	7,440,518	7,440,518
Common stock, shares outstanding	6,950,786	6,935,471
Treasury stock, at cost	489,732	505,047