Common and preferred stock (Details Textual) (USD $)	9 Months Ended		260 Months Ended											9 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Oct. 31, 2012	Jun. 27, 2012	May 17, 2012	Mar. 31, 2012	Feb. 08, 2012	Dec. 31, 2011	Sep. 30, 2012 Senior convertible notes due august 15 2015 [Member]	Dec. 31, 2011 Senior convertible notes due august 15 2015 [Member]	Aug. 31, 2010 Senior convertible notes due august 15 2015 [Member]	May 17, 2012 Other Than Equity [Member]	Sep. 30, 2012 Warrant Liability [Member]	Feb. 08, 2012 Warrant Liability [Member]	Sep. 30, 2012 Mann Group [Member]	Sep. 30, 2012 Mann Group [Member] Forward Purchase Contracts [Member]	May 17, 2012 Mann Group [Member] Forward Purchase Contracts [Member]	Mar. 31, 2012 Mann Group [Member] Forward Purchase Contracts [Member]	Sep. 30, 2012 Mann Group [Member] Forward Purchase Contracts [Member] Equity Component [Member]	Sep. 30, 2012 Mann Group [Member] Forward Purchase Contracts [Member] Other Than Equity [Member]	May 17, 2012 Mann Group [Member] Forward Purchase Contracts [Member] Other Than Equity [Member]	Feb. 08, 2012 Underwriters [Member]	Feb. 08, 2012 Public [Member]
Class of Stock [Line Items]
Principal amount										$ 100,000,000	$ 100,000,000	$ 100,000,000
Senior notes, effective interest rate										5.75%		5.75%
Number of Unit Sold in an Underwritten public offering								35,937,500															4,687,500
Purchased Price of the units by underwriters																							2.256	2.40
Number of warrants are exercisable								21,562,500							21,562,500
Rate at which warrants are exercisable				2.60				2.40							2.40
Duration for Expiration of warrants														4 years
Authorized shares under common stock purchase agreement																250,000,000
Proposal to increase the authorized share	350,000,000		350,000,000						250,000,000							350,000,000
Number of Shares that recorded the portion of the derivative instrument representing equity																				14,700,000
Fair value of the forward purchase contract																			2,000,000	900,000	1,100,000
Other Expenses																	12,000,000
Risk Free Interest Rate	0.10%		0.10%			0.18%																0.08%
Discount for lack of marketability						1.67%												10.27%
Capital stock authorized	131,522,945		131,522,945		31,250,000				131,522,945							31,250,000
Restricted common stock price per share																$ 2.47
Fair value of Non-Equity Portion													13,100,000
Related Party Transaction [Line Items]
Common stock, shares issued	199,767,463		199,767,463						199,767,463
Common and Preferred Stock (Textual) [Abstract]
Units sold composition description								each unit consisting of one share of common stock and a warrant to purchase 0.6 of a share of common stock
Warrant to purchase of a share of common stock								0.6
Net proceeds from offering	80,982,000	10,544,000	1,311,003,000
Restricted Stock Agreed to be Purchased by Lender								77,200,000
Undesignated preferred stock, par value	$ 0.01		$ 0.01						$ 0.01
Capital stock authorized	131,522,945		131,522,945		31,250,000				131,522,945							31,250,000
Common stock loaned under share lending agreement, shares	9,000		9,000
Time required for returning shares after payment of entire debt	45 days
Nominal lending fee	$ 0.01
Derivative Portion Balance in Current Assets							800,000
Change in fair value recognized in other income	$ 12,000,000		$ 12,000,000
Number of Shares that recorded the portion of the derivative instrument representing outside of equity							16,700,000
Valuation of non-equity portion of forward contract						$ 1.69		$ 2.40