CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Common stock, per share	$ 0.52	$ 0.51	$ 0.47
Preferred stock Series H
Preferred stock, per share	1,275.00	1,275.00	796.88
Preferred stock Series I
Preferred stock, per share	1,656.24	1,757.46
Preferred stock Series J
Preferred stock, per share	$ 1,225.00	$ 391.32
Preferred stock Series G
Preferred stock, per share			$ 1,074.31