Commitments and Contingencies - Additional Information (Details)			3 Months Ended		9 Months Ended
	Apr. 16, 2018 USD ($)	Aug. 26, 2008	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) lease	Sep. 30, 2018 USD ($)	Jun. 30, 2019 ft²	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
Commitments And Contingencies [Line Items]
Number of leases | lease					2
Assets under capital lease			$ 400,000		$ 400,000
Capital lease interest expense obligation			100,000		100,000
Gross fixed assets for capital leases				$ 300,000		$ 300,000
Capital lease depreciation expense			0		100,000
Capital lease depreciation expense				0		100,000
Increase ROU asset					246,000	0
Increase lease liability					$ 202,000	0
Service contract term					3 years
ROU asset			2,393,000		$ 2,393,000			$ 1,566,000	$ 0
Operating Lease Obligations			2,546,000		2,546,000
Rent, lease amortization and interest expense			100,000		300,000
Rent, lease amortization and interest expense				$ 200,000		500,000
Right-of-use assets			$ 0		$ 2,592,000	0
Weighted average discount rate			9.00%		9.00%
Remaining term on lease liabilities			5 years 11 months		5 years 11 months
Initial term of agreement	3 years
Bio Valve
Commitments And Contingencies [Line Items]
Upfront license, signing fees and development milestone payments		9.00%
Upfront license, signing fees and development milestone payments, certain circumstances		10.00%
Amounts owed			$ 0		$ 0				$ 0
Integration fee
Commitments And Contingencies [Line Items]
Agreement payment	$ 100,000
Annual maintenance fee
Commitments And Contingencies [Line Items]
Agreement payment	$ 100,000
First Amendment to the Marlborough Massachusetts lease
Commitments And Contingencies [Line Items]
Square feet | ft²							4,076
Increase ROU asset					800,000
Increase lease liability						$ 800,000
Right-of-use assets			0		2,600,000
Embedded lease
Commitments And Contingencies [Line Items]
ROU asset			200,000		200,000
Operating Lease Obligations			$ 200,000		$ 200,000