Consolidated Balance Sheets (unaudited) (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred Stock, shares authorized	100,000,000	100,000,000
Preferred Stock, shares issued	5,200,000	5,200,000
Preferred stock, shares outstanding	5,200,000	5,200,000
Common stock, par value (per share)	$ 1.00	$ 1.00
Common stock, shares authorized	342,857,143	342,857,143
Common stock, shares issued	142,441,418	142,025,720
Common stock, shares outstanding	122,321,804	122,266,106
Treasury stock, shares at cost	20,119,614	19,759,614