Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value per share	$ 0.1	$ 0.1
Authorized to issue of shares	80,000,000	80,000,000
Common stock, shares issued	30,235,164	30,235,164
Treasury shares at cost	5,362,684	1,428,495