Summary of Significant Accounting Policies - Summary of Depreciation and Amortization Recorded using Straight-line Method over Estimated Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2018
Computers and Telecommunications [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	3 years
Computers and Telecommunications [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	5 years
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	3 years
Furniture, Fixtures and Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	5 years
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	7 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	Lesser of lease term or estimated useful lives