Consolidated Statements of Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements Of Stockholders' Equity (Parenthetical) [Abstract]
Common stock, dividends, per share, declared	$ 1.64	$ 1.64	$ 1.64