| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| | | Additions | | | | |
| Balance at beginning of period | | Charged to costs and expenses | | Charged to other accounts | | Reductions | | Balance at end of period |
| | | | | | | | | |
| (in millions) |
| Deferred tax asset valuation allowance: | | | | | | | | | |
| Year ended December 31, 2023 | $ | 2,058 | | | $ | (96) | | | $ | — | | (1) | $ | — | | | $ | 1,962 | |
| Year ended December 31, 2022 | $ | 1,638 | | | $ | 398 | | | $ | 22 | | (1) | $ | — | | | $ | 2,058 | |
| Year ended December 31, 2021 | $ | 677 | | | $ | 53 | | | $ | 908 | | (1) | $ | — | | | $ | 1,638 | |