Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Loss Contingencies [Line Items]
Minimum lease payments	$ 10,068,000	$ 10,068,000		$ 10,068,000
Future minimum sublease income	100,000	100,000		100,000
Rent expense		500,000	$ 400,000	1,000,000	$ 800,000
Revolving Credit Facility | secured Debt
Loss Contingencies [Line Items]
Line of credit drawn amount	0	0		0
Revolving Credit Facility | secured Debt | Western Alliance Bank
Loss Contingencies [Line Items]
Line of credit facility	15,000,000	$ 15,000,000		$ 15,000,000
Line of credit facility, expiration date				Jun. 30, 2018
Revolving Credit Facility | secured Debt | Western Alliance Bank | Prime Rate
Loss Contingencies [Line Items]
Line of credit, interest rate				0.75%
Massachusetts
Loss Contingencies [Line Items]
Minimum lease payments						$ 7,800,000
China
Loss Contingencies [Line Items]
Increase in future minimum payments	800,000
United Kingdom
Loss Contingencies [Line Items]
Increase in future minimum payments	$ 200,000