Summary of Significant Accounting Policies - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment	$ 791	$ 630
Less accumulated depreciation	(98)	(76)
Property and equipment, net	693	554
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment	182	182
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment	248	185
Equipment
Property Plant And Equipment [Line Items]
Property and equipment	219	219
Computer Software and Hardware
Property Plant And Equipment [Line Items]
Property and equipment	$ 142	$ 44

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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