Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments	$ 195.7	$ 192.2
Transfers into Level 3	8.1	23.1
Transfers out of Level 3	0.1	$ 5.7
Fair Value Measured at Net Asset Value Per Share
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value, Unfunded Commitments	110.4
Partnership Interest [Member] | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments	$ 195.7