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Stock-based Compensation - Additional Information (Details) - USD ($)		1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	May 28, 2020	Jun. 30, 2020	Feb. 29, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense		$ 20,900,000		$ 20,900,000		$ 20,900,000		$ 1,300,000
Unrecognized stock-based compensation weighted-average period						1 year 10 months 24 days		2 years 4 months 24 days
Weighted average fair value per share						$ 3.97
Aggregate intrinsic value of options outstanding		303,100,000		303,100,000		$ 303,100,000
Aggregate intrinsic value of options exercisable		167,500,000		167,500,000		$ 167,500,000
Granted, Shares						2,214,276
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				600,000	$ 700,000	$ 1,200,000	$ 1,500,000
Unrecognized stock-based compensation expense		4,700,000		4,700,000		$ 4,700,000		$ 5,200,000
Unrecognized stock-based compensation weighted-average period						2 years 8 months 12 days		2 years 7 months 6 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				3,300,000	$ 0	$ 3,300,000	$ 0
Award acceleration period						12 months
RSUs \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				500,000		$ 500,000
Granted, Shares			367,782
RSUs \| Service Periods Vest Ranging from 12 to 48 Months \| IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		510,278,000
RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance									4,751,874	4,751,874
Stock-based compensation expense				200,000		200,000
Unrecognized stock-based compensation expense		$ 0		$ 0		$ 0
Maximum \| RSUs \| Service Periods Vest Ranging from 12 to 48 Months \| IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Continuous service period		48 months
Minimum [Member] \| RSUs \| Service Periods Vest Ranging from 12 to 48 Months \| IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Continuous service period		12 months
2020 Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance		3,093,498		3,093,498		3,093,498
2020 Incentive Award Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	3,019,108
Percentage annual increase in shares available for issuance as award in each year beginning	4.00%