Statement of Changes in Consolidated Equity (unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Common stock, dividends per share	$ 0.12	$ 0.18
Preferred Class A [Member]
Preferred, dividends per share	0.9375	0.9375
Preferred Class B [Member]
Preferred, dividends per share	$ 6.71875	$ 6.71875