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Fair Value Measurements - Quantitative Information for Level 3 Measurements (Details) - Recurring Fair Value Measurements | Dec. 31, 2023 USD ($) item | Dec. 31, 2022 USD ($) item
--- | --- | ---
Unobservable inputs |  |
Assets measured at fair value | $ | $ 240,637,600,000 | $ 225,470,300,000
Liabilities measured at fair value | $ | 1,823,400,000 | 2,764,400,000
Fair value hierarchy Level 3 |  |
Unobservable inputs |  |
Assets measured at fair value | $ | 5,130,200,000 | 3,447,300,000
Liabilities measured at fair value | $ | 2,317,600,000 | 3,394,900,000
Fair value hierarchy Level 3 | Investment and universal life contracts |  |
Unobservable inputs |  |
Liabilities measured at fair value | $ | $ (115,500,000) | $ (46,400,000)
Embedded derivative, Valuation technique | Discounted cash flow | Discounted cash flow
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long duration interest rate | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.025 | 0.024
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long duration interest rate | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.048 | 0.047
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long duration interest rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.031
Embedded derivative, Input | 0.040 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long-term equity market volatility | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.155 | 0.178
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long-term equity market volatility | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.401 | 0.369
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long-term equity market volatility | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.192 | 0.220
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk |  |
Unobservable inputs |  |
Embedded derivative, Input |  | 0.009
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.008 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.016 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.011 | 0.009
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate |  |
Unobservable inputs |  |
Embedded derivative, Input |  | 0.000
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.000 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.550 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.070 | 0.000
Fair value hierarchy Level 3 | Fixed maturities | Trading |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 203,900,000 | $ 119,700,000
Fair value hierarchy Level 3 | Fixed maturities | Trading | Discounted cash flow | Discount rate | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.096
Fixed maturities, trading, Input | 0.114 |
Fair value hierarchy Level 3 | Fixed maturities | Trading | Discounted cash flow | Discount rate | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.152
Fixed maturities, trading, Input | 0.223 |
Fair value hierarchy Level 3 | Fixed maturities | Trading | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.110
Fixed maturities, trading, Input | 0.133 |
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 1,997,400,000 | $ 1,479,900,000
Fixed maturities, available-for-sale, Valuation technique | Discounted cash flow | Discounted cash flow
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Discount rate | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.049 | 0.027
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Discount rate | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.242 | 0.331
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.120 | 0.110
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Earnings before interest, taxes, depreciation and amortization multiple |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 3.25 |
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Earnings before interest, taxes, depreciation and amortization multiple | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 3.25 |
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Illiquidity premium | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0030 | 0
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Illiquidity premium | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0483 | 0.0467
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Illiquidity premium | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0121 | 0.0050
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Comparability adjustment | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0067 | (0.0016)
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Comparability adjustment | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0217 | 0
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Comparability adjustment | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0141 | (0.0011)
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 74,600,000 | $ 39,500,000
Fixed maturities, available-for-sale, Valuation technique | Discounted cash flow | Discounted cash flow
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Discount rate |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.041 | 0.044
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.041 | 0.044
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Comparability adjustment |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0020 | 0.0055
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Comparability adjustment | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0020 | 0.0055
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 879,500,000 | $ 467,800,000
Fixed maturities, available-for-sale, Valuation technique | Discounted cash flow | Discounted cash flow
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Discount rate | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.050 | 0.056
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Discount rate | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.106 | 0.082
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.074 | 0.076
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Illiquidity premium | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0069 | 0
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Illiquidity premium | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0650 | 0.0260
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Illiquidity premium | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0337 | 0.0220
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Comparability adjustment | Minimum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | (0.0020) | 0.0001
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Comparability adjustment | Maximum |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0213 | 0.0139
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Comparability adjustment | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0092 | 0.0077
Fair value hierarchy Level 3 | Other investments |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 163,200,000 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Discount rate | Minimum |  |
Unobservable inputs |  |
Other investments, Input | 0.120 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Discount rate | Maximum |  |
Unobservable inputs |  |
Other investments, Input | 0.135 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input | 0.126 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Probability of default | Minimum |  |
Unobservable inputs |  |
Other investments, Input | 0.060 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Probability of default | Maximum |  |
Unobservable inputs |  |
Other investments, Input | 0.100 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Probability of default | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input | 0.085 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Potential loss severity | Minimum |  |
Unobservable inputs |  |
Other investments, Input | 0.870 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Potential loss severity | Maximum |  |
Unobservable inputs |  |
Other investments, Input | 1.000 |
Fair value hierarchy Level 3 | Other investments | Discounted cash flow | Potential loss severity | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input | 0.907 |
Fair value hierarchy Level 3 | Separate account assets |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 752,800,000 | $ 1,034,100,000
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Discount rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.065 | 0.055
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Discount rate | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.100 | 0.100
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.075 | 0.070
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Terminal capitalization rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.053 | 0.045
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Terminal capitalization rate | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.095 | 0.095
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Terminal capitalization rate | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.061 | 0.058
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Average market rent growth rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.020 | 0.020
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Average market rent growth rate | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.037 | 0.038
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Average market rent growth rate | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.029 | 0.030
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Loan to value | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.460 | 0.436
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Loan to value | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.720 | 0.622
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Loan to value | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.553 | 0.506
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Market interest rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.053 | 0.053
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Market interest rate | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.081 | 0.086
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Market interest rate | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.064 | 0.066

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