Statement of Changes in Consolidated Equity (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement Of Stockholders Equity [Abstract]
Preferred, dividends per share	$ 0.9375	$ 0.9375	$ 1.875	$ 1.875
Common stock, dividends per share	$ 0.03	$ 0.03	$ 0.06	$ 0.06