Nature of Business (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 Program	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Nature of Business [Abstract]
Number of programs in clinical development for cancer indications	2
Estimated Projected Expenditure Type [Line Items]
Cash and cash equivalents	$ 32,218,905	$ 11,483,112	$ 14,344,088	$ 17,988,590
Short-term investments	45,621,593	27,084,980
Projected expenditures for clinical programs	58,600,000
Aldoxorubicin [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs	43,900,000
Albumin-Binding Cancer Drugs [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs	2,000,000
General Operation [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs	3,800,000
Other General and Administrative Expenses [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs	$ 8,900,000