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Investments - Mortgage Loan Credit Monitoring (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022
Vintage year, Direct financing leases |  |
2023 | $ 46.1 |
2022 | 145.5 | $ 147.1
2021 | 48.8 | 93.8
2020 | 111.6 | 114.4
2019 | 12.9 | 15.3
2018 |  | 54.6
Prior |  | 239.8
Prior | 285.2 |
Direct financing leases, Total amortized cost | 650.1 | 665.0
Reinsurance recoverable and deposit receivable | 20,614.9 | 21,445.4
Accrued interest receivable | 619.2 | 578.0
Accrued interest receivable on direct financing leases | 1.2 | 0.0
A- and above |  |
Vintage year, Direct financing leases |  |
2023 | 1.1 |
2022 | 122.0 | 110.5
2021 | 12.4 | 13.0
2020 | 56.7 | 39.9
2019 | 1.3 | 1.4
2018 |  | 42.9
Prior |  | 167.3
Prior | 207.3 |
Direct financing leases, Total amortized cost | 400.8 | 375.0
BBB+ thru BBB- |  |
Vintage year, Direct financing leases |  |
2023 | 2.8 |
2022 | 23.5 | 33.9
2021 | 20.8 | 21.9
2020 | 46.9 | 62.4
2019 | 11.6 | 11.9
2018 |  | 11.7
Prior |  | 70.4
Prior | 76.3 |
Direct financing leases, Total amortized cost | 181.9 | 212.2
BB+ thru BB- |  |
Vintage year, Direct financing leases |  |
2023 | 42.2 |
2022 |  | 2.7
2021 | 15.6 | 57.3
2020 | 8.0 | 12.1
2019 |  | 2.0
Prior |  | 2.1
Prior | 1.6 |
Direct financing leases, Total amortized cost | 67.4 | 76.2
B+ and below |  |
Vintage year, Direct financing leases |  |
2021 |  | 1.6
Direct financing leases, Total amortized cost |  | 1.6
Commercial mortgage loans |  |
Vintage year, Mortgage loans |  |
2023 | 1,057.7 |
2022 | 1,775.3 | 1,526.0
2021 | 2,755.5 | 2,734.3
2020 | 1,802.0 | 1,967.1
2019 | 2,410.3 | 2,628.9
2018 |  | 2,444.0
Prior | 6,781.0 | 5,430.0
Mortgage loans, Total amortized cost | 16,581.8 | 16,730.3
Vintage year, Direct financing leases |  |
Accrued interest receivable | 58.3 | 57.7
Commercial mortgage loans | A- and above |  |
Vintage year, Mortgage loans |  |
2023 | 664.8 |
2022 | 1,277.1 | 1,036.4
2021 | 2,364.0 | 2,277.9
2020 | 1,587.3 | 1,807.3
2019 | 1,954.4 | 2,210.2
2018 |  | 2,187.9
Prior | 5,576.6 | 4,624.9
Mortgage loans, Total amortized cost | 13,424.2 | 14,144.6
Commercial mortgage loans | BBB+ thru BBB- |  |
Vintage year, Mortgage loans |  |
2023 | 282.4 |
2022 | 356.0 | 385.6
2021 | 374.8 | 439.6
2020 | 212.0 | 156.8
2019 | 337.3 | 418.7
2018 |  | 238.9
Prior | 911.7 | 691.7
Mortgage loans, Total amortized cost | 2,474.2 | 2,331.3
Commercial mortgage loans | BB+ thru BB- |  |
Vintage year, Mortgage loans |  |
2023 | 110.5 |
2022 | 142.2 | 104.0
2021 | 16.7 | 16.8
2020 | 2.7 | 3.0
2019 | 35.2 |
2018 |  | 8.9
Prior | 234.2 | 71.7
Mortgage loans, Total amortized cost | 541.5 | 204.4
Commercial mortgage loans | B+ and below |  |
Vintage year, Mortgage loans |  |
2019 | 83.4 |
2018 |  | 8.3
Prior | 58.5 | 41.7
Mortgage loans, Total amortized cost | 141.9 | 50.0
Residential mortgage loans |  |
Vintage year, Mortgage loans |  |
2023 | 503.4 |
2022 | 1,068.3 | 1,152.8
2021 | 1,346.7 | 1,745.4
2020 | 229.7 | 449.3
2019 | 122.8 | 134.7
2018 |  | 76.0
Prior | 425.6 | 424.8
Mortgage loans, Total amortized cost | 3,696.5 | 3,983.0
Vintage year, Direct financing leases |  |
Accrued interest receivable | 11.4 | 19.6
Residential mortgage loans | Performing |  |
Vintage year, Mortgage loans |  |
2023 | 502.3 |
2022 | 1,064.3 | 1,144.8
2021 | 1,341.8 | 1,740.7
2020 | 228.4 | 447.1
2019 | 120.8 | 133.0
2018 |  | 75.4
Prior | 421.0 | 417.8
Mortgage loans, Total amortized cost | 3,678.6 | 3,958.8
Residential mortgage loans | Non-performing |  |
Vintage year, Mortgage loans |  |
2023 | 1.1 |
2022 | 4.0 | 8.0
2021 | 4.9 | 4.7
2020 | 1.3 | 2.2
2019 | 2.0 | 1.7
2018 |  | 0.6
Prior | 4.6 | 7.0
Mortgage loans, Total amortized cost | $ 17.9 | 24.2
Vintage year, Direct financing leases |  |
Mortgage loans, delinquent to be considered non-performing (in days) | 90 days |
Other loans |  |
Vintage year, Mortgage loans |  |
2023 | $ 168.5 |
Prior | 0.1 |
Mortgage loans, Total amortized cost | 168.6 |
Vintage year, Direct financing leases |  |
Accrued interest receivable | 1.6 | $ 0.0
Other loans | Performing |  |
Vintage year, Mortgage loans |  |
2023 | 168.5 |
Mortgage loans, Total amortized cost | 168.5 |
Other loans | Non-performing |  |
Vintage year, Mortgage loans |  |
Prior | 0.1 |
Mortgage loans, Total amortized cost | $ 0.1 |

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- Definition Amount excluding accrued interest, before allowance for credit loss, of net investment in direct financing lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 + Details
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