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Fair Value Measurements - Quantitative Information for Level 3 Measurements (Details) - Recurring Fair Value Measurements $ in Millions | Sep. 30, 2021 USD ($) item | Dec. 31, 2020 USD ($) item
--- | --- | ---
Unobservable inputs |  |
Assets measured at fair value | $ | $ 260,148.7 | $ 259,883.4
Liabilities measured at fair value | $ | (600.0) | (654.3)
Fair value hierarchy Level 3 |  |
Unobservable inputs |  |
Assets measured at fair value | $ | 2,163.3 | 9,286.1
Liabilities measured at fair value | $ | (356.0) | (473.5)
Fair value hierarchy Level 3 | Investment and universal life contracts |  |
Unobservable inputs |  |
Liabilities measured at fair value | $ | $ (355.3) | $ (467.8)
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 | 0.019 | 0.012
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long duration interest rate | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.021 | 0.014
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 | 0.020 | 0.013
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long-term equity market volatility | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.179 | 0.176
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Long-term equity market volatility | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.320 | 0.269
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 | 0.221 | 0.196
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.002 | 0.001
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.010 | 0.014
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Non-performance risk | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.008 | 0.009
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate | Minimum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.000 | 0.000
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate | Maximum |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.170 | 0.160
Fair value hierarchy Level 3 | Investment and universal life contracts | Discounted cash flow | Lapse rate | Weighted average input |  |
Unobservable inputs |  |
Embedded derivative, Input | 0.051 | 0.058
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 746.9 | $ 286.1
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 | 0.007 | 0.009
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 | 0.186 | 0.117
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 | 0.070 | 0.073
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 | 0.0070 | 0.0060
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 | 0.0007 | 0.0019
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
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 |  | 0.0769
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 |  | 0.0359
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Probability of default |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 1.000 | 1.000
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Probability of default | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 1.000 | 1.000
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Potential loss severity |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.164 | 0.546
Fair value hierarchy Level 3 | Corporate debt securities | Available-for-sale | Discounted cash flow | Potential loss severity | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.164 | 0.546
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 2.7 | $ 1.1
Fixed maturities, available-for-sale, Valuation technique | Discounted cash flow | Discounted cash flow
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale | Discounted cash flow | Discount rate |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.039 |
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale | Discounted cash flow | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.039 |
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale | Discounted cash flow | Probability of default |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 1.000
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale | Discounted cash flow | Probability of default | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 1.000
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale | Discounted cash flow | Potential loss severity |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.784
Fair value hierarchy Level 3 | Commercial mortgage-backed securities | Available-for-sale | Discounted cash flow | Potential loss severity | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.784
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 1.0 | $ 0.7
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 | 0.030 |
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 | 0.030 |
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Illiquidity premium |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0291 |
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Illiquidity premium | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input | 0.0291 |
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Probability of default |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 1.000
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Probability of default | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 1.000
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Potential loss severity |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.405
Fair value hierarchy Level 3 | Collateralized debt obligations | Available-for-sale | Discounted cash flow | Potential loss severity | Weighted average input |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.405
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 22.2 | $ 0.8
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 |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.100
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 | 0.025 |
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 | 0.100 |
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 | 0.028 | 0.100
Fair value hierarchy Level 3 | Other debt obligations | Available-for-sale | Discounted cash flow | Illiquidity premium |  |
Unobservable inputs |  |
Fixed maturities, available-for-sale, Input |  | 0.0500
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 | 0.0225 |
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 | 0.0500 |
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 | 0.0500
Fair value hierarchy Level 3 | Other investments |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 1.3 | $ 30.4
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, other investments | Discount rate | Minimum |  |
Unobservable inputs |  |
Other investments, Input |  | 0.250
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, other investments | Discount rate | Maximum |  |
Unobservable inputs |  |
Other investments, Input |  | 0.300
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, other investments | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 0.275
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, other investments | Terminal earnings before interest, taxes, depreciation and amortization multiple | Minimum |  |
Unobservable inputs |  |
Other investments, Input |  | 3.8
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, other investments | Terminal earnings before interest, taxes, depreciation and amortization multiple | Maximum |  |
Unobservable inputs |  |
Other investments, Input |  | 4.7
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, other investments | Terminal earnings before interest, taxes, depreciation and amortization multiple | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 4.2
Fair value hierarchy Level 3 | Other investments | Market comparables | Revenue multiples | Minimum |  |
Unobservable inputs |  |
Other investments, Input | 6.8 | 6.0
Fair value hierarchy Level 3 | Other investments | Market comparables | Revenue multiples | Maximum |  |
Unobservable inputs |  |
Other investments, Input | 9.1 | 8.0
Fair value hierarchy Level 3 | Other investments | Market comparables | Revenue multiples | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input | 8.0 | 7.0
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate | Discount rate |  |
Unobservable inputs |  |
Other investments, Input |  | 0.065
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 0.065
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate | Terminal capitalization rate |  |
Unobservable inputs |  |
Other investments, Input |  | 0.053
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate | Terminal capitalization rate | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 0.053
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate | Average market rent growth rate |  |
Unobservable inputs |  |
Other investments, Input |  | 0.026
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate | Average market rent growth rate | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 0.026
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate debt | Credit spread rate |  |
Unobservable inputs |  |
Other investments, Input |  | 0.033
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate debt | Credit spread rate | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 0.033
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate debt | Loan to value |  |
Unobservable inputs |  |
Other investments, Input |  | 0.526
Fair value hierarchy Level 3 | Other investments | Discounted cash flow, real estate debt | Loan to value | Weighted average input |  |
Unobservable inputs |  |
Other investments, Input |  | 0.526
Fair value hierarchy Level 3 | Separate account assets |  |
Unobservable inputs |  |
Assets measured at fair value | $ | $ 1,268.0 | $ 8,893.2
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, mortgage loans | Discount rate |  |
Unobservable inputs |  |
Separate account assets, Input | 0.012 | 0.012
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, mortgage loans | Discount rate | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.012 | 0.012
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, mortgage loans | Illiquidity premium |  |
Unobservable inputs |  |
Separate account assets, Input | 0.0060 | 0.0060
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, mortgage loans | Illiquidity premium | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.0060 | 0.0060
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, mortgage loans | Credit spread rate |  |
Unobservable inputs |  |
Separate account assets, Input | 0.0109 | 0.0110
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, mortgage loans | Credit spread rate | Weighted average input |  |
Unobservable inputs |  |
Separate account assets, Input | 0.0109 | 0.0110
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Discount rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.055 | 0.056
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Discount rate | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.119 | 0.119
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 | 0.069
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate | Terminal capitalization rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.045 | 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 | 0.093 | 0.093
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 | 0.059 | 0.057
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 | 0.015 | 0.015
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 | 0.036 | 0.048
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 | 0.028 | 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 | 0.290 | 0.063
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Loan to value | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.602 | 0.742
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 | 0.436 | 0.475
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Market interest rate | Minimum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.023 | 0.020
Fair value hierarchy Level 3 | Separate account assets | Discounted cash flow, real estate debt | Market interest rate | Maximum |  |
Unobservable inputs |  |
Separate account assets, Input | 0.045 | 0.050
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 | 0.028 | 0.034

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