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Accumulated Other Comprehensive Loss (AOCL) (Tables) | 12 Months Ended
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Dec. 31, 2023
Additional financial information disclosures [Abstract] |
Components of Accumulated Other Comprehensive Loss |
Components of AOCL | 2023 |  | 2022
Defined benefit plan liabilities | $ | (101.8) |  |  | $ | (98.0) |
Unrealized gain on financial instruments | 1.6 |  |  | 1.7 |
Other comprehensive loss before income tax effect | (100.2) |  |  | (96.3) |
Income tax effect(1) | 2.3 |  |  | 2.3 |
Accumulated other comprehensive loss | $ | (97.9) |  |  | $ | (94.0) |
(1)The allocation of the income tax effect to the components of other comprehensive loss is as follows:
| 2023 |  | 2022
Defined benefit plan liabilities | $ | 2.6 |  |  | $ | 2.6 |
Unrealized loss on financial instruments | (0.3) |  |  | (0.3) |
The following table summarizes the changes in the accumulated balances for each component of AOCL:
| Defined benefit plan and other postretirement liabilities |  | Unrealized gain (loss) on financial instruments |  | Total, net of tax
Balance, December 31, 2020 | $ | (120.6) |  |  | $ | 1.8 |  |  | $ | (118.8) |
Other comprehensive income (loss) before reclassifications | 31.6 |  |  | — |  |  | 31.6 |
Net amount reclassified to net income (loss) | 5.0 |  |  | (0.1) |  |  | 4.9 |
Balance, December 31, 2021 | (84.0) |  |  | 1.7 |  |  | (82.3) |
Other comprehensive income (loss) before reclassifications | (5.9) |  |  | — |  |  | (5.9) |
Net amount reclassified to net income (loss) | (5.7) |  |  | (0.1) |  |  | (5.8) |
Balance, December 31, 2022 | (95.6) |  |  | 1.6 |  |  | (94.0) |
Other comprehensive income (loss) before reclassifications | (10.1) |  |  | — |  |  | (10.1) |
Net amount reclassified to net income (loss) | 6.3 |  |  | (0.1) |  |  | 6.2 |
Balance, December 31, 2023 | $ | (99.4) |  |  | $ | 1.5 |  |  | $ | (97.9) |
Reclassification out of AOCL | Reclassifications out of AOCL were included in the consolidated statements of operations as follows:
|  |  |  | Year Ended December 31,
AOCL Components |  | Location |  | 2023 |  | 2022 |  | 2021
Defined benefit plan and other postretirement liabilities |  | Cost of goods sold |  | $ | (1.0) |  |  | $ | 3.5 |  |  | $ | 26.8 |
|  | Other income, net |  | — |  |  | (8.9) |  |  | — |
|  | Selling, general and administrative expenses |  | (0.2) |  |  | 3.3 |  |  | 2.9 |
|  | Other operating expense (income), net |  | (2.6) |  |  | (9.0) |  |  | 7.3 |
|  | Income tax expense |  | — |  |  | (0.3) |  |  | (0.4) |
|  | Net of tax |  | $ | (3.8) |  |  | $ | (11.4) |  |  | $ | 36.6 |
Gain (loss) on financial instruments |  | Cost of goods sold |  | $ | (0.1) |  |  | $ | (0.2) |  |  | $ | (0.1) |
|  | Income tax effect |  | $ | — |  |  | (0.1) |  |  | 0.0 |
|  | Net of tax |  | $ | (0.1) |  |  | $ | (0.3) |  |  | $ | (0.1) |

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