Schedule of Participating Mortgage Loans by Internal Credit Rating and Loan to Value (Details) - USD ($) $ in Millions		Jun. 30, 2025	Dec. 31, 2024
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	[1]	$ 2,172.5	$ 2,224.5
Mortgage Loans, Percent of Total		100.00%	100.00%
Loan to Value Ratio Below or Equal to 65 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 1,612.3	$ 1,639.6
Mortgage Loans, Percent of Total		74.20%	73.80%
Loan To Value Ratio Above 65 To 75 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 327.5	$ 367.6
Mortgage Loans, Percent of Total		15.10%	16.50%
Loan To Value Ratio Above 75 To 85 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 169.1	$ 152.3
Mortgage Loans, Percent of Total		7.80%	6.80%
Loan To Value Ratio Above 85 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 63.6	$ 65.0
Mortgage Loans, Percent of Total		2.90%	2.90%
AA Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 95.2	$ 117.8
Mortgage Loans, Percent of Total		4.40%	5.30%
A Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 1,073.9	$ 1,099.1
Mortgage Loans, Percent of Total		49.40%	49.40%
BBB Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 885.9	$ 915.5
Mortgage Loans, Percent of Total		40.80%	41.20%
BB Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 101.4	$ 85.0
Mortgage Loans, Percent of Total		4.70%	3.80%
B Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount		$ 16.1	$ 7.1
Mortgage Loans, Percent of Total		0.70%	0.30%

[1] 1Loan-to-Value Ratio utilizes the most recent internal valuation of the property