Investments - Schedule of Commercial Mortgage Loan Participations Recorded Investment (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	$ 381,315		$ 279,199
Carrying value	388,517		282,871
Less allowance for credit losses	$ (7,202)	$ (5,826)	$ (3,672)	$ (2,988)	$ (2,928)	$ (1,789)
Carrying value, net of valuation allowance, percent	100.00%		100.00%
Less than 70%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value	$ 364,101		$ 266,216
Carrying value, net of valuation allowance, percent	94.00%		94.00%
70% to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value	$ 1,058		$ 0
Carrying value, net of valuation allowance, percent	0.00%		0.00%
81% to 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value	$ 8,569		$ 9,621
Carrying value, net of valuation allowance, percent	2.00%		3.00%
Greater than 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value	$ 14,789		$ 7,034
Carrying value, net of valuation allowance, percent	4.00%		3.00%
Less Than 1.00x
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	$ 47,257		$ 42,593
Less Than 1.00x | Less than 70%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	22,841		27,091
Less Than 1.00x | 70% to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	1,058		0
Less Than 1.00x | 81% to 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	8,569		8,468
Less Than 1.00x | Greater than 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	14,789		7,034
1.00x-1.20x
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	138,034		180,761
1.00x-1.20x | Less than 70%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	138,034		180,761
1.00x-1.20x | 70% to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	0		0
1.00x-1.20x | 81% to 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	0		0
1.00x-1.20x | Greater than 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	0		0
Greater Than 1.20x
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	203,226		59,517
Greater Than 1.20x | Less than 70%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	203,226		58,364
Greater Than 1.20x | 70% to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	0		0
Greater Than 1.20x | 81% to 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	0		1,153
Greater Than 1.20x | Greater than 90%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value, net of valuation allowance	$ 0		$ 0