Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Statement Of Financial Position [Abstract]
Preferred stock, stated value	$ 1,000	$ 1,000	$ 1,000
Preferred stock, shares authorized	5,000,000	5,000,000	5,000,000
Preferred stock, shares issued	28,000	28,000	52,000
Preferred stock, shares outstanding	28,000	28,000	52,000
Common stock, par value	$ 1	$ 1	$ 1
Common stock, shares authorized	100,000,000	100,000,000	100,000,000
Common stock, shares issued	25,257,669	25,154,818	25,155,318
Treasury stock, shares	1,363,342	1,355,050	1,336,174