Liquidity and Capital Resources (Details) (USD $)	6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Estimated projected expenditure [Line Items]
Cash and cash equivalents	$ 10,980,486	$ 14,344,088	$ 11,859,009	$ 17,988,590
Marketable securities	17,000,000	24,000,000
Currently projected expenditures for clinical programs	20,700,000
Aldoxorubicin [Member]
Estimated projected expenditure [Line Items]
Currently projected expenditures for clinical programs	8,100,000
Tamibarotene and Bafetinib [Member]
Estimated projected expenditure [Line Items]
Currently projected expenditures for clinical programs	1,200,000
General Operation [Member]
Estimated projected expenditure [Line Items]
Currently projected expenditures for clinical programs	4,700,000
Other General and Administrative Expenses [Member]
Estimated projected expenditure [Line Items]
Currently projected expenditures for clinical programs	$ 6,700,000