Common Stock (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Common stock, authorized (in shares)	150,000,000	150,000,000
Par value of common stock (in dollars per share)	$ 0.001	$ 0.001
Common stock, issued	18,817,572	15,313,297
Common Stock, Outstanding (in shares)	18,817,572	15,313,297
Common Stock, Dividends, Declared or Paid	$ 0
Shares reserved for future issuance (in shares)	3,300,018	2,799,213
Warrants for the purchase of Common Stock
Shares reserved for future issuance (in shares)	24,566	59,405
Options to purchase Common Stock
Shares reserved for future issuance (in shares)	2,939,968	2,557,456
Employee Stock Purchase Plan
Shares reserved for future issuance (in shares)	335,484	182,352