Leases - Operating Leases (Details)	1 Months Ended	6 Months Ended
	Jan. 31, 2019 USD ($)	Jun. 30, 2020 USD ($) ft² lease agreement item	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Number of real estate leases | lease		2
Weighted average remaining term of the operating leases		5 years 7 months 6 days
Right-of-use assets		$ 14,864,000		$ 15,587,000
Lease liabilities		$ 23,334,000
Unamortized lease incentive and straight-line lease liability balances	$ 9,700,000
Weighted-average discount rate		11.00%
Lease expense for operating lease payments		$ 2,000,000.0	$ 2,300,000
Cash paid against operating lease liabilities		2,700,000	2,600,000
Operating lease right-of-use asset impairment			559,000
Sublease income		713,000
Maximum
Lessee, Lease, Description [Line Items]
100 basis point change effect on ROU asset		$ 1,000,000
CRP/King 830 Winter L.L.C.
Lessee, Lease, Description [Line Items]
Actively seeking to sub-lease, area available | ft²		65,000
Number of executed sub-lease spaces | lease		3
Area of executed sublease space | ft²		47,000
Area of space leased | ft²		120,000
Number of additional terms for which lease agreement can be extended | item		2
Operating lease term extension period		5 years
PDM 930 Unit, LLC
Lessee, Lease, Description [Line Items]
Area of executed sublease space | ft²		10,281
Winter Street 930 Waltham MA
Lessee, Lease, Description [Line Items]
Number of executed sub-lease spaces | agreement		3
Area of executed sublease space | ft²		47,160
Minimum rental payments over the remaining term of the sublease		$ 13,000,000.0
Leasehold impairment charge			$ 559,000
ASU 2016-2 | Restatement Adjustment
Lessee, Lease, Description [Line Items]
Right-of-use assets	17,600,000
Lease liabilities	$ 27,300,000