Stockholder's Equity (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended				91 Months Ended		6 Months Ended	0 Months Ended		1 Months Ended	3 Months Ended					0 Months Ended		3 Months Ended	0 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Jun. 30, 2013	Jan. 17, 2013	Jun. 30, 2013 June 21, 2012 Equity sales agreement	Jan. 17, 2013 Callisto Merger Agreement	Oct. 18, 2012 CRO stock purchase agreement	Jan. 31, 2013 CRO stock purchase agreement	Dec. 31, 2012 CRO stock purchase agreement	Jun. 30, 2013 CRO stock purchase agreement	Mar. 31, 2013 CRO stock purchase agreement	Dec. 31, 2012 CRO stock purchase agreement	Oct. 17, 2012 CRO stock purchase agreement	Apr. 16, 2013 April 2013 Registered Direct Offering	Nov. 14, 2011 November 14, 2011 securities purchase agreements	Jun. 30, 2013 November 14, 2011 securities purchase agreements	Dec. 01, 2011 November 14, 2011 securities purchase agreements Selling agent
Stockholder's Equity
Number of authorized shares of common stock	200,000,000	100,000,000	200,000,000		100,000,000				200,000,000	100,000,000
Stockholder's Equity
Common stock issued (in shares)											758,093									16,375,000
Common stock price (in dollars per share)											$ 6.16		$ 4.55							$ 5.50
Gross proceeds from sale of common stock by the entity			$ 94,734,000	$ 51,750,000					$ 211,168,000		$ 4,700,000									$ 90,000,000
Stock issuance costs			5,623,000	3,358,000					12,346,000		100,000									5,500,000
Number of units sold																					1,328,941
Number of units issued for services (in units)																							77,750
Number of shares of common stock per unit																					1
Number of warrants per unit																					1
Number of common shares that can be acquired upon exercise of each warrant																					1
Fair value of derivative liabilities reclassified to equity	3,575,000	169,000																				3,600,000
Derivative liability marked to market																						870,000
Fair value of common stock issued for services rendered			250,000		93,000	341,000	18,000	2,000								250,000
Percentage of services completed of total contract															50.00%
Fair value of common stock issued for services rendered (in shares)																	55,000
Closing stock price (in dollars per share)																			$ 4.57
Stock based compensation expense			2,168,000	792,000					7,652,000					125,000				125,000
Percentage of the total contract													25.00%
Shares issued in connection with merger												28,605,379
Exchange Ratio of shares												0.1799
Cancellation of stock (in shares)												22,294,976
Lock-up period												18 months
Shares granted in connection with merger												1,221,316
Assets
Security deposits												74,000
Total assets acquired												74,000
Liabilities
Accounts payable and other liabilities												(1,400,000)
Net assumed liabilities												(1,326,000)
Elimination of amounts due from Callisto												(3,578,000)
Recapitalization of Synergy			$ (4,904,000)						$ (4,904,000)			$ (4,904,000)