Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2015

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured at Fair Value

The following table presents financial assets and liabilities measured at fair value as of June 30, 2015:

	Fair Value Measurement at Report Date Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Unobservable Inputs (Level 3)		As of June 30, 2015
Financial assets:
Cash equivalents:
Money market funds	$	971,527	$	—	$	—	$	971,527
U.S. Treasury debt obligations		26,654,879		—		—		26,654,879
Total financial assets	$	27,626,406	$	—	$	—	$	27,626,406
Financial liabilities:
Loan payable net of discounts		—		—		12,383,018		12,383,018
Warrant liabilities		—		—		1,043,514		1,043,514
Total financial liabilities	$	—	$	—	$	13,426,532	$	13,426,532

Roll Forward for Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3)

The following table presents a roll forward for liabilities measured at fair value using significant unobservable inputs (Level 3) for 2015:

	Warrant liabilities
Balance at March 31, 2015	$	2,031,881
Less change in fair value of warrants		(988,367	)
Balance at June 30, 2015	$	1,043,514

	Loan payable net of discounts
Balance at March 31, 2015	$	13,372,796
Add amortization of discount		26,612
Less repayments of principal		(1,016,390	)
Balance at June 30, 2015	$	12,383,018
Current portion		3,466,377
Non-current portion		8,916,641
Balance at June 30, 2015	$	12,383,018