Revenue from Contracts with Customer - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Deferred revenues	$ 196,297,000		$ 196,297,000		$ 209,314,000
Contract asset impairment			0		0
Contract with customer, liability, revenue recognized			164,539,000	$ 177,462,000
Contract with customer liability additions			157,680,000	142,678,000
Total revenues	$ 248,480,000	$ 202,997,000	$ 693,416,000	$ 581,977,000
Customer Concentration Risk | Revenue Benchmark | Channel Partners
Disaggregation of Revenue [Line Items]
Concentration risk percentage	7.00%	8.00%	7.00%	8.00%
Portfolio Balancing
Disaggregation of Revenue [Line Items]
Deferred revenues	$ 18,504,000		$ 18,504,000		$ 18,166,000
Licenses
Disaggregation of Revenue [Line Items]
Total revenues	108,524,000	$ 85,369,000	292,034,000	$ 245,639,000
Term Licenses
Disaggregation of Revenue [Line Items]
Total revenues	$ 96,658,000	$ 72,542,000	$ 258,661,000	$ 209,619,000