Revenue Recognition - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Deferred sales commissions current	$ 11,400,000		$ 11,400,000		$ 9,900,000
Deferred sales commissions noncurrent	15,500,000		15,500,000		14,200,000
Amortization expense for the deferred costs	3,500,000	$ 1,900,000	9,200,000	$ 5,500,000
Impairment loss related to costs capitalized			0		$ 0
Subscription Services and License
Disaggregation Of Revenue [Line Items]
Revenue recognized	54,300,000	36,900,000	110,700,000	77,000,000.0
Professional Services
Disaggregation Of Revenue [Line Items]
Revenue recognized	5,100,000	$ 4,100,000	6,000,000.0	$ 5,200,000
Revenue remaining performance obligation	8,700,000		8,700,000
Subscription and Other Contracts
Disaggregation Of Revenue [Line Items]
Revenue remaining performance obligation	$ 322,600,000		$ 322,600,000