Revenue from Contracts with Customers - Additional Information (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Agreements for product and product-related services revenue				1 year
Agreements for product and product-related services revenue, description				The Company’s agreements for product and product-related services revenue have an expected duration of one year or less
Product and product-related services revenue	$ 2,023,312	$ 1,458,345		$ 3,756,858	$ 2,829,514
Contract liabilities	448,717			448,717		$ 837,885
Collaborative development services	2,887,454	302,411		5,312,560	302,411
Cumulative catch up adjustment	0			30,055
Collaborative Development Services
Disaggregation Of Revenue [Line Items]
Contract liabilities	118,125			$ 118,125		245,942
Bristol Myers Squibb
Disaggregation Of Revenue [Line Items]
Agreement expiration date				May 11, 2019
Number of days material breach remains uncured				60 days
Agreement termination notice period				90 days
Product and product-related services revenue	70,919		$ 31,250	$ 132,224	62,500
Contract liabilities	90,382			90,382		$ 160,106
Partially unsatisfied performance obligation aggregate amount	50,000			50,000
Merck KGaA Agreement | Collaborative Development Services
Disaggregation Of Revenue [Line Items]
Collaborative development services	$ 0	$ 25,000		$ 0	$ 25,000
Minimum
Disaggregation Of Revenue [Line Items]
Customer payment term				30 days
Maximum
Disaggregation Of Revenue [Line Items]
Customer payment term				90 days