Commitment and Contingencies (Details) ft² in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) ft²	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Other Commitments [Line Items]
Area of leased space | ft²	22,000
Monthly base rent	$ 113,246
Rate of increase for monthly base rent	3.00%
Option to extend	5 years
Total commitment	$ 10,500,000
Tenant improvement allowance	$ 1,500,000
Deferred rent		$ 4,800,000		$ 4,800,000		$ 5,100,000
Rent expense		2,400,000	$ 2,500,000	7,300,000	$ 7,600,000
Contractual commitments		48,500,000		48,500,000
Other liabilities
Other Commitments [Line Items]
Deferred rent		$ 3,900,000		$ 3,900,000		$ 4,600,000