Fair Value Measurements (excluding Consolidated Investment Entities) - Fair Value Measurement (Details) - USD ($) $ in Millions | Jun. 30, 2024 | Dec. 31, 2023 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Assets held in separate accounts | $ 99,147 | $ 93,133 |
Total assets | 161,280 | 157,085 |
Derivatives | 316 | 371 |
Total liabilities | 155,411 | 151,032 |
Fixed maturities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 27,472 | 28,611 |
U.S. Treasuries | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 349 | 403 |
U.S. Government agencies and authorities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 54 | 56 |
State, municipalities and political subdivisions | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 630 | 771 |
U.S. corporate public securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 7,137 | 7,666 |
U.S. corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 4,696 | 4,760 |
Foreign corporate public securities and foreign governments | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,520 | 2,702 |
Foreign corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,660 | 2,812 |
Residential mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,378 | 3,476 |
Commercial mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,388 | 3,495 |
Other asset-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,660 | 2,470 |
Measured at fair value on a recurring basis | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreements | 2,194 | 2,165 |
Assets held in separate accounts | 99,147 | 93,133 |
Total assets | 129,431 | 124,517 |
Contingent consideration | 49 | 51 |
Total liabilities | 421 | 480 |
Measured at fair value on a recurring basis | Stabilizer and MCGs | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Guaranteed benefit derivatives | 10 | 9 |
Measured at fair value on a recurring basis | Interest rate contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 269 | 270 |
Derivatives | 308 | 354 |
Measured at fair value on a recurring basis | Foreign exchange contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 43 | 37 |
Derivatives | 3 | 13 |
Measured at fair value on a recurring basis | Equity contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 4 | 4 |
Derivatives | 3 | 2 |
Measured at fair value on a recurring basis | Embedded derivative on reinsurance | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 62 | 61 |
Embedded derivative on reinsurance | 46 | 49 |
Measured at fair value on a recurring basis | Credit contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 2 | 2 |
Measured at fair value on a recurring basis | Fixed maturities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 27,472 | 28,611 |
Measured at fair value on a recurring basis | U.S. Treasuries | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 349 | 403 |
Measured at fair value on a recurring basis | U.S. Government agencies and authorities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 54 | 56 |
Measured at fair value on a recurring basis | State, municipalities and political subdivisions | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 630 | 771 |
Measured at fair value on a recurring basis | U.S. corporate public securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 7,137 | 7,666 |
Measured at fair value on a recurring basis | U.S. corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 4,696 | 4,760 |
Measured at fair value on a recurring basis | Foreign corporate public securities and foreign governments | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,520 | 2,702 |
Measured at fair value on a recurring basis | Foreign corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,660 | 2,812 |
Measured at fair value on a recurring basis | Residential mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,378 | 3,476 |
Measured at fair value on a recurring basis | Commercial mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,388 | 3,495 |
Measured at fair value on a recurring basis | Other asset-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,660 | 2,470 |
Measured at fair value on a recurring basis | Equity securities, at fair value | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Equity securities | 240 | 236 |
Measured at fair value on a recurring basis | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreements | 2,180 | 2,148 |
Assets held in separate accounts | 93,081 | 87,180 |
Total assets | 95,678 | 89,821 |
Contingent consideration | 0 | 0 |
Total liabilities | 3 | 0 |
Measured at fair value on a recurring basis | Level 1 | Stabilizer and MCGs | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Guaranteed benefit derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Interest rate contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 7 |
Derivatives | 3 | 0 |
Measured at fair value on a recurring basis | Level 1 | Foreign exchange contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Equity contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Embedded derivative on reinsurance | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Embedded derivative on reinsurance | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Credit contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Fixed maturities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 275 | 346 |
Measured at fair value on a recurring basis | Level 1 | U.S. Treasuries | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 275 | 346 |
Measured at fair value on a recurring basis | Level 1 | U.S. Government agencies and authorities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | State, municipalities and political subdivisions | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | U.S. corporate public securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | U.S. corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Foreign corporate public securities and foreign governments | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Foreign corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Residential mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Commercial mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Other asset-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 1 | Equity securities, at fair value | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Equity securities | 142 | 140 |
Measured at fair value on a recurring basis | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreements | 14 | 17 |
Assets held in separate accounts | 5,703 | 5,605 |
Total assets | 31,282 | 32,162 |
Contingent consideration | 0 | 0 |
Total liabilities | 302 | 362 |
Measured at fair value on a recurring basis | Level 2 | Stabilizer and MCGs | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Guaranteed benefit derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 2 | Interest rate contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 269 | 263 |
Derivatives | 305 | 354 |
Measured at fair value on a recurring basis | Level 2 | Foreign exchange contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 43 | 37 |
Derivatives | 3 | 13 |
Measured at fair value on a recurring basis | Level 2 | Equity contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 4 | 4 |
Derivatives | 3 | 2 |
Measured at fair value on a recurring basis | Level 2 | Embedded derivative on reinsurance | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 62 | 61 |
Embedded derivative on reinsurance | (11) | (9) |
Measured at fair value on a recurring basis | Level 2 | Credit contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 2 | 2 |
Measured at fair value on a recurring basis | Level 2 | Fixed maturities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 25,187 | 26,175 |
Measured at fair value on a recurring basis | Level 2 | U.S. Treasuries | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 74 | 57 |
Measured at fair value on a recurring basis | Level 2 | U.S. Government agencies and authorities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 54 | 55 |
Measured at fair value on a recurring basis | Level 2 | State, municipalities and political subdivisions | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 630 | 771 |
Measured at fair value on a recurring basis | Level 2 | U.S. corporate public securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 7,125 | 7,648 |
Measured at fair value on a recurring basis | Level 2 | U.S. corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,232 | 3,234 |
Measured at fair value on a recurring basis | Level 2 | Foreign corporate public securities and foreign governments | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,503 | 2,702 |
Measured at fair value on a recurring basis | Level 2 | Foreign corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,216 | 2,376 |
Measured at fair value on a recurring basis | Level 2 | Residential mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,329 | 3,419 |
Measured at fair value on a recurring basis | Level 2 | Commercial mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 3,388 | 3,495 |
Measured at fair value on a recurring basis | Level 2 | Other asset-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,636 | 2,418 |
Measured at fair value on a recurring basis | Level 2 | Equity securities, at fair value | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Equity securities | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreements | 0 | 0 |
Assets held in separate accounts | 363 | 348 |
Total assets | 2,471 | 2,534 |
Contingent consideration | 49 | 51 |
Total liabilities | 116 | 118 |
Measured at fair value on a recurring basis | Level 3 | Stabilizer and MCGs | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Guaranteed benefit derivatives | 10 | 9 |
Measured at fair value on a recurring basis | Level 3 | Interest rate contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | Foreign exchange contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | Equity contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | Embedded derivative on reinsurance | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Embedded derivative on reinsurance | 57 | 58 |
Measured at fair value on a recurring basis | Level 3 | Credit contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivatives | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | Fixed maturities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 2,010 | 2,090 |
Measured at fair value on a recurring basis | Level 3 | U.S. Treasuries | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | U.S. Government agencies and authorities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 1 |
Measured at fair value on a recurring basis | Level 3 | State, municipalities and political subdivisions | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | U.S. corporate public securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 12 | 18 |
Measured at fair value on a recurring basis | Level 3 | U.S. corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 1,464 | 1,526 |
Measured at fair value on a recurring basis | Level 3 | Foreign corporate public securities and foreign governments | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 17 | 0 |
Measured at fair value on a recurring basis | Level 3 | Foreign corporate private securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 444 | 436 |
Measured at fair value on a recurring basis | Level 3 | Residential mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 49 | 57 |
Measured at fair value on a recurring basis | Level 3 | Commercial mortgage-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 0 | 0 |
Measured at fair value on a recurring basis | Level 3 | Other asset-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Fixed maturities, including securities pledged | 24 | 52 |
Measured at fair value on a recurring basis | Level 3 | Equity securities, at fair value | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Equity securities | $ 98 | $ 96 |