Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Consolidated Balance Sheets [Abstract]
Common stock, par value per share	$ 0.1	$ 0.1	$ 0.1
Common stock, shares authorized	80,000,000	80,000,000	80,000,000
Common stock, shares issued	30,235,164	30,235,164	30,235,164
Common stock, shares outstanding	30,235,164	30,235,164	30,235,164
Treasury shares, at cost	888,336	1,011,356	869,699