Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares authorized	3,800,917	3,800,917
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.50	$ 0.50
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares outstanding	53,490,603	53,039,688