Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
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	0	0	0
Preferred stock, shares outstanding	0	0	0
Common stock, par value	$ 1	$ 1	$ 1
Common stock, shares authorized	100,000,000	100,000,000	100,000,000
Common stock, shares issued	33,608,866	28,159,027	28,155,317
Treasury stock, shares	1,413,777	1,385,164	1,383,496