Fair Value - Narrative (Details)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	$ 87,667,000	$ 51,762,000
Fair value assets level 2 to level 3 transfers amount	0
Contingent consideration liability	$ 251,522,000	247,309,000
CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration liability			$ 227,100,000
Revenue growth rate | Minimum | CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Acquisition-related contingent liability (as percent)	0.020		0.020
Revenue growth rate | Maximum | CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Acquisition-related contingent liability (as percent)	0.839		0.839
Revenue growth rate | Weighted Average | CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Acquisition-related contingent liability (as percent)	0.103		0.115
Discount rate | Minimum | CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Acquisition-related contingent liability (as percent)	0.019		0.019
Discount rate | Maximum | CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Acquisition-related contingent liability (as percent)	0.104		0.104
Discount rate | Weighted Average | CarVal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Acquisition-related contingent liability (as percent)	0.046		0.045
Other
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	$ 2,972,000	1,486,000
Mutual Fund | Level 1 | Other
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investments, fair value disclosure	7,000,000	6,700,000
Start-up company
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	300,000	300,000
Broker dealer exchange memberships
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	$ 2,700,000	$ 1,200,000