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Fair Value Measurements - Quantitative Information for Level 3 Measurements (Details) - Recurring Fair Value Measurements $ in Millions | Sep. 30, 2023 USD ($) item | Dec. 31, 2022 USD ($) item
--- | --- | ---
Unobservable inputs |  |
Assets measured at fair value | $ | $ 223,946.1 | $ 225,470.3
Liabilities measured at fair value | $ | 3,178.0 | 2,764.4
Fair value hierarchy Level 3 |  |
Unobservable inputs |  |
Assets measured at fair value | $ | 4,552.8 | 3,447.3
Liabilities measured at fair value | $ | 3,836.4 | 3,394.9
Fair value hierarchy Level 3 | Investment and universal life contracts |  |
Unobservable inputs |  |
Liabilities measured at fair value | $ | $ (78.8) | $ (46.4)
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 | 0.029 | 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 | 0.055 | 0.047
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long duration interest rate | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.043 | 0.031
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long-term equity market volatility | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.152 | 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 | 0.426 | 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 | 0.195 | 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 | 0.009 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.018 |
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.012 | 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 | 0.052 | 0.000
Fair value hierarchy Level 3 | Fixed maturities | Trading |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 152.3 | $ 119.7
Fair value hierarchy Level 3 | Fixed maturities | Trading | Discounted cash flow | Discount rate | Minimum |  |
Unobservable inputs |  |
Fixed maturities, trading, Input | 0.113 | 0.096
Fair value hierarchy Level 3 | Fixed maturities | Trading | Discounted cash flow | Discount rate | Maximum |  |
Unobservable inputs |  |
Fixed maturities, trading, Input | 0.199 | 0.152
Fair value hierarchy Level 3 | Fixed maturities | Trading | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, trading, Input | 0.132 | 0.110
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 1,756.4 | $ 1,479.9
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 | 0.062 | 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 | 0.260 | 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 | 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 | 0.0482 | 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 | 0.0096 | 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 |  | (0.0016)
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
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 |  | (0.0011)
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 54.3 | $ 39.5
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 | 0.051 | 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 | 0.051 | 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 | 0.0047 | 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 | 0.0047 | 0.0055
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 741.9 | $ 467.8
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 | 0.063 | 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 | 0.118 | 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 | 0.090 | 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 | 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 | 0.0235 | 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 | 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 | 0.0158 | 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 | 0.0108 | 0.0077
Fair value hierarchy Level 3 | Separate account assets |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 764.7 | $ 1,034.1
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Discount rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.050 | 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 | 0.065 | 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 | 0.058 | 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 | 0.069 | 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 | 0.034 | 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 | 0.477 | 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 | 0.674 | 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 | 0.528 | 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 | 0.052 | 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 | 0.066 | 0.066

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