Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2018
Computers and equipment [Member]
Property and equipment, estimated useful life	5 years
Website development [Member]
Property and equipment, estimated useful life	3 years
Furniture and fixtures [Member]
Property and equipment, estimated useful life	7 years
Leasehold improvements [Member]
Property and equipment, estimated useful life	Shorter of estimated useful life or remaining lease term