Basis of Presentation (Details)	3 Months Ended
	Mar. 31, 2012
Basis of Presentation (Textual) [Abstract]
Economic interest in unconsolidated investments in voting rights entities, minimum	20.00%
Economic interest in unconsolidated investments in voting rights entities, maximum	50.00%
Economic interest in unconsolidated investments in voting rights entities, Ownership less than	20.00%