Fair Value Measurement (Details 2) (Warrant liabilities [Member], USD $)	6 Months Ended
Jun. 30, 2012
Warrant liabilities [Member]
Roll forward for liabilities measured at fair value using significant unobservable inputs (Level 3)
Balance at December 31, 2011	$ 6,011,120
Less fair value of warrants exercised	(1,095,801)
Less fair value of warrants expired	(3,560,063)
Add fair value of warrants issued	1,714,436
Add change in fair value of warrants	2,320,326
Balance at June 30, 2012	$ 5,390,018

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant