Employee Benefit Plans - Summary of Stock-based Compensation Expense Recognized in Financial Statements (Details) - USD ($) $ in Thousands		3 Months Ended
	Sep. 25, 2018	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of amounts capitalized	$ 89,900	$ 15,111	$ 8,540
Capitalized stock-based compensation expense		953	328
Stock-based compensation expense		16,064	8,868
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of amounts capitalized		1,096	658
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of amounts capitalized		4,766	3,447
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of amounts capitalized		2,780	768
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of amounts capitalized		$ 6,469	$ 3,667