Common Equity (Details 3) (USD $)	1 Months Ended	12 Months Ended
	Jan. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Non-vested options
Outstanding, Shares, Beginning Balance	10,638,750.0
Outstanding, Weighted-Average Exercise Price, Beginning	$ 21.65
Granted, shares	938,770
Granted, Weighted-Average Exercise Price		$ 3.17	$ 3.36	$ 4.01
Outstanding, Shares, Ending Balance		10,638,750.0
Outstanding, Weighted-Average Exercise Price, Ending		$ 21.65
Non-Vested Options [Member]
Non-vested options
Outstanding, Shares, Beginning Balance		5,272,570.0
Outstanding, Weighted-Average Exercise Price, Beginning		$ 4.27
Granted, shares		458,180.0
Granted, Weighted-Average Exercise Price		$ 3.17
Vested, shares		(2,626,980.0)
Vested, Weighted-Average Exercise Price		$ 4.64
Forfeited, shares		0.0
Forfeited, Weighted-Average Exercise Price		$ 0.00
Outstanding, Shares, Ending Balance		3,103,770.0
Outstanding, Weighted-Average Exercise Price, Ending		$ 3.78