Commitments and Contingencies (Details Textual) $ in Thousands		1 Months Ended	6 Months Ended
	Aug. 29, 2020 ft²	Jun. 30, 2021 USD ($) ft²	Jun. 30, 2021 USD ($) ft²	Jun. 30, 2020 USD ($)	Aug. 01, 2013 ft²
Commitments And Contingencies [Line Items]
Area of office facilities taken on lease | ft²	5,200				5,300
Operating lease term	42 months
Additional operating lease term	36 months
Weighted-average discount rate	7.00%	7.00%	7.00%
Lease renewal option	option to renew for an additional 36 month term at the then prevailing rental rate.
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Area of additional office facilities taken on sublease | ft²		3,000	3,000
Operating sublease term		29 months
Lessee, Operating Sublease, Existence of Option to Extend [true false]		false
Lessee, operating lease, assumptions and judgments, allocation of lease and nonlease component			The leases include real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation.
Operating lease, cash paid for measurement of lease liabilities			$ 29	$ 51
Lease liability		$ 522	$ 522
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]		Accrued expenses and other liabilities	Accrued expenses and other liabilities
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]		Operating lease liability, net of current portion	Operating lease liability, net of current portion
Weighted-average remaining lease term		5 years 2 months 12 days	5 years 2 months 12 days
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense			$ 47	$ 48