Property and Equipment, Net - Schedule of Property and Equipment (Parenthetical) (Details) - Leasehold improvements	9 Months Ended
	Sep. 30, 2019
Property Plant And Equipment [Line Items]
Property and equipment, useful life in years	5 years	[1]
Maximum
Property Plant And Equipment [Line Items]
Lease term	5 years
Property and equipment, useful life in years	5 years

[1] Lesser of the lease term or the estimated useful lives of the improvements, which may be up to 5 years.