Income Taxes - Schedule of Reconciliation between U.S. Federal Statutory Tax Rate and Effective Tax Rate (Details)		12 Months Ended
	Dec. 22, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%	34.00%
Tax credits		17.70%	4.80%
State taxes, net of federal tax benefit		5.50%	5.00%
Change in tranche liability			(1.00%)
Non-deductible expenses		(0.30%)	(1.80%)
Impact of federal rate change			(15.20%)
Change in valuation allowance		(43.90%)	(25.80%)