Commitments and Contingencies - Schedule of Property and Equipment Amounts for Capital Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Sep. 30, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 6,373	$ 6,370
Less: accumulated depreciation and amortization	(2,982)	(3,831)
Property and equipment, net	3,391	$ 2,539
Capital Lease Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	686
Less: accumulated depreciation and amortization	(471)
Property and equipment, net	$ 215
Capital Lease Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful life	3 years
Capital Lease Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful life	5 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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