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v3.23.1

Fair Value Measurements - Changes in balances of Level 3 financial assets carried at fair value (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2021
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | $ 1,102 | $ 926 |  |
Total realized/unrealized gains (losses) included in Net income | 1 | 23 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 6 | (21) |  |
Purchases and issuances | 84 | 105 |  |
Sales and settlements | (41) | (27) |  |
Transfer into Level 3 | 4 | 37 |  |
Transfer out of Level 3 | (28) | (45) |  |
Financial assets, Ending Balance | 1,128 | 998 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value | (25) | (23) | $ (25) | $ (23)
Contingent consideration — acquisitions |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value | (25) | (23) | $ (25) | $ (23)
Fixed maturities |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 664 | 600 |  |
Total realized/unrealized gains (losses) included in Net income | 5 | 2 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 6 | (21) |  |
Purchases and issuances | 51 | 75 |  |
Sales and settlements | (19) | (24) |  |
Transfer into Level 3 | 4 | 34 |  |
Transfer out of Level 3 | (6) | (41) |  |
Financial assets, Ending Balance | 705 | 625 |  |
U.S. government agency |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 0 | 0 |  |
Total realized/unrealized gains (losses) included in Net income | 0 | 0 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | 0 |  |
Purchases and issuances | 0 | 0 |  |
Sales and settlements | 0 | 0 |  |
Transfer into Level 3 | 0 | 0 |  |
Transfer out of Level 3 | 0 | 0 |  |
Financial assets, Ending Balance | 0 | 0 |  |
State and municipal |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 5 | 41 |  |
Total realized/unrealized gains (losses) included in Net income | 0 | 0 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | (2) |  |
Purchases and issuances | 0 | 0 |  |
Sales and settlements | 0 | (1) |  |
Transfer into Level 3 | 0 | 0 |  |
Transfer out of Level 3 | 0 | (5) |  |
Financial assets, Ending Balance | 5 | 33 |  |
Residential MBS |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 9 | 14 |  |
Total realized/unrealized gains (losses) included in Net income | 0 | 0 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | 0 |  |
Purchases and issuances | 0 | 0 |  |
Sales and settlements | (3) | (1) |  |
Transfer into Level 3 | 4 | 0 |  |
Transfer out of Level 3 | (5) | (2) |  |
Financial assets, Ending Balance | 5 | 11 |  |
Commercial MBS |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 0 | 0 |  |
Total realized/unrealized gains (losses) included in Net income | 0 | 0 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | 0 |  |
Purchases and issuances | 0 | 0 |  |
Sales and settlements | 0 | 0 |  |
Transfer into Level 3 | 0 | 0 |  |
Transfer out of Level 3 | 0 | 0 |  |
Financial assets, Ending Balance | 0 | 0 |  |
Collateralized loan obligations |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 2 | 0 |  |
Total realized/unrealized gains (losses) included in Net income | 0 | 0 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | 0 |  |
Purchases and issuances | 0 | 0 |  |
Sales and settlements | 0 | 0 |  |
Transfer into Level 3 | 0 | 0 |  |
Transfer out of Level 3 | (1) | 0 |  |
Financial assets, Ending Balance | 1 | 0 |  |
Other asset-backed securities |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 329 | 278 |  |
Total realized/unrealized gains (losses) included in Net income | 0 | 2 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 4 | (9) |  |
Purchases and issuances | 7 | 47 |  |
Sales and settlements | (5) | (15) |  |
Transfer into Level 3 | 0 | 34 |  |
Transfer out of Level 3 | 0 | 0 |  |
Financial assets, Ending Balance | 335 | 337 |  |
Corporate and other |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 319 | 267 |  |
Total realized/unrealized gains (losses) included in Net income | 5 | 0 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 2 | (10) |  |
Purchases and issuances | 44 | 28 |  |
Sales and settlements | (11) | (7) |  |
Transfer into Level 3 | 0 | 0 |  |
Transfer out of Level 3 | 0 | (34) |  |
Financial assets, Ending Balance | 359 | 244 |  |
Equity securities |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 427 | 313 |  |
Total realized/unrealized gains (losses) included in Net income | (3) | 22 |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | 0 |  |
Purchases and issuances | 31 | 30 |  |
Sales and settlements | (22) | (3) |  |
Transfer into Level 3 | 0 | 3 |  |
Transfer out of Level 3 | (22) | (4) |  |
Financial assets, Ending Balance | 411 | 361 |  |
Assets of MIE |  |  |  |
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Financial assets, Beginning Balance | 11 | 13 |  |
Total realized/unrealized gains (losses) included in Net income | (1) | (1) |  |
Total realized/unrealized gains (losses) included in other comprehensive income (loss) | 0 | 0 |  |
Purchases and issuances | 2 | 0 |  |
Sales and settlements | 0 | 0 |  |
Transfer into Level 3 | 0 | 0 |  |
Transfer out of Level 3 | 0 | 0 |  |
Financial assets, Ending Balance | $ 12 | $ 12 |  |

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