Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2017

Fair Value Disclosures [Abstract]

Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following tables show assets measured at fair value on a recurring basis as of March 31, 2017 and December 31, 2016:

	March 31, 2017
(in thousands)	Level 1		Level 2		Level 3
Assets:
Money market funds	$	7,386	$	—	$	—
Totals	$	7,386	$	—	$	—
Liabilities:
Silver Creek warrant liability	$	—	$	—	$	2,926
Totals	$	—	$	—	$	2,926

	December 31, 2016
(in thousands)	Level 1		Level 2		Level 3
Assets:
Money market funds	$	12,373	$	—	$	—
Totals	$	12,373	$	—	$	—
Liabilities:
Silver Creek warrant liability	$	—	$	—	$	1,499
Totals	$	—	$	—	$	1,499