Goodwill and Intangible Assets - Summary of Finite-Lived Intangible Assets (Details) $ in Millions	Dec. 31, 2023 USD ($)
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	20 years
At inception:	$ 231.0
Accumulated amortization and impairments:	(74.1)
Total	$ 156.9
Value of business acquired
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	28 years
At inception:	$ 100.1
Accumulated amortization and impairments:	(35.3)
Total	$ 64.8
Value of distribution acquired
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	17 years
At inception:	$ 54.0
Accumulated amortization and impairments:	$ (17.5)
Value of agency relationships
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	14 years
At inception:	$ 17.0
Accumulated amortization and impairments:	$ (9.8)
Value of customer relationships
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	10 years
At inception:	$ 59.9
Accumulated amortization and impairments:	$ (11.5)