Property, Equipment and Leasehold Improvements - Schedule of Property, Equipment and Leasehold Improvements (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property, equipment and leasehold improvements, gross	$ 6,205,486	$ 5,316,567
Less: accumulated depreciation	(1,977,999)	(1,733,531)
Property, equipment and leasehold improvements, net	4,227,487	3,583,036
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property, equipment and leasehold improvements, gross	4,469,663	3,757,265
Office Equipment
Property Plant And Equipment [Line Items]
Property, equipment and leasehold improvements, gross	649,824	577,418
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property, equipment and leasehold improvements, gross	$ 1,085,999	$ 981,884

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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