Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2018
Recurring | Convertible senior note
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible senior note net	$ 597,800
Conversable, Inc. and AdvntageTec
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent earn-out				$ 2,400
Contingent earn-out
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent earn-out increase (decrease)	100		$ 600
Equity issued as payment for contingent consideration			(300)
Contingent earn-out | AdvantageTec
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Re-measurement to fair value increase (decrease)	$ 132	$ (263)	$ 300