Organization (Details)	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Feb. 23, 2009
Organization (Textual) [Abstract]
Number of operating segments	3
Outstanding stock percentage	48.20%
Stock ownership percentage owned by third party	51.80%
Voting power percentage of outstanding common stock	66.67%
Percentage of share in results of pooled business owned by third party	20.00%
Subsidiaries [Member]
Schedule of Capitalization, Equity [Line Items]
Percentage of share in results of pooled business	80.00%
Common Class A [Member]
Schedule of Capitalization, Equity [Line Items]
Stock ownership percentage held by major shareholder	39.00%
Number of common stock shares purchased			300,000
Common stock shares purchased	182,392	50,058
Common Class A [Member] | Subsidiaries [Member]
Schedule of Capitalization, Equity [Line Items]
Common stock shares purchased	45,764
Common Class B [Member]
Schedule of Capitalization, Equity [Line Items]
Stock ownership percentage held by major shareholder	75.00%