Securities - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Investment [Line Items]
Allowance for securities credit losses	$ 0	$ 0
Debt securities, available-for-sale, realized gain (loss)	(697,000)	(108,000)
Equity investments	100,163,000	102,037,000
Corporate debt securities
Investment [Line Items]
Allowance for securities credit losses	0	0
Amortized cost	78,800,000
Fair value	74,300,000
State, municipal and sovereign debt obligations
Investment [Line Items]
Amortized cost	62,500,000
Fair value	60,900,000
Asset-backed securities
Investment [Line Items]
Allowance for securities credit losses	0	$ 0
Amortized cost	295,800,000
Fair value	$ 291,500,000