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Mortgage Loans by Property Type and Geographic Region (Detail) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount | [1],[2] | $ 2,129.8 | $ 2,224.5
Mortgage Loans, Percent of Total | [2] | 100.00% | 100.00%
New England |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 50.6 | $ 52.6
Mortgage Loans, Percent of Total |  | 2.40% | 2.40%
Mid-Atlantic |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 161.7 | $ 167.2
Mortgage Loans, Percent of Total |  | 7.60% | 7.50%
East North Central |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 275.7 | $ 297.2
Mortgage Loans, Percent of Total |  | 12.90% | 13.40%
West North Central |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 145.6 | $ 151.1
Mortgage Loans, Percent of Total |  | 6.80% | 6.80%
South Atlantic |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 508.1 | $ 532.5
Mortgage Loans, Percent of Total |  | 23.90% | 23.90%
East South Central |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 86.5 | $ 95.1
Mortgage Loans, Percent of Total |  | 4.10% | 4.30%
West South Central |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 184.8 | $ 193.6
Mortgage Loans, Percent of Total |  | 8.70% | 8.70%
Mountain |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 271.5 | $ 278.7
Mortgage Loans, Percent of Total |  | 12.70% | 12.50%
Pacific |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 445.3 | $ 456.5
Mortgage Loans, Percent of Total |  | 20.90% | 20.50%
Apartment |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 657.1 | $ 658.2
Mortgage Loans, Percent of Total |  | 30.90% | 29.60%
Industrial |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 662.0 | $ 690.4
Mortgage Loans, Percent of Total |  | 31.10% | 31.00%
Office |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 319.9 | $ 338.4
Mortgage Loans, Percent of Total |  | 15.00% | 15.20%
Retail |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 462.9 | $ 496.2
Mortgage Loans, Percent of Total |  | 21.70% | 22.30%
Other Property |  |  |
Mortgage Loans on Real Estate |  |  |
Mortgage Loans, Carrying Amount |  | $ 27.9 | $ 41.3
Mortgage Loans, Percent of Total |  | 1.30% | 1.90%
[1] | 1 Loan-to-Value Ratio utilizes the most recent internal valuation of the property
[2] | Loan-to-Value Ratio utilizes the most recent internal valuation of the property

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