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Accumulated Other Comprehensive Loss (AOCL) (Tables) | 12 Months Ended
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Dec. 31, 2020
Additional financial information disclosures [Abstract] |
Components of Accumulated Other Comprehensive Loss |
Components of AOCL | 2020 |  | 2019
Defined benefit plan liabilities | $ | (123.7) |  |  | $ | (115.9) |
Unrealized gain (loss) on financial instruments | 2.1 |  |  | 2.3 |
Other comprehensive loss before income tax effect | (121.6) |  |  | (113.6) |
Income tax effect(1) | 2.8 |  |  | 3.8 |
Accumulated other comprehensive loss | $ | (118.8) |  |  | $ | (109.8) |
(1)The allocation of the income tax effect to the components of other comprehensive loss is as follows:
| 2020 |  | 2019
Defined benefit plan liabilities | $ | 3.2 |  |  | $ | 4.3 |
Unrealized loss on financial instruments | (0.4) |  |  | (0.4) |
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, 2017 | $ | (93.8) |  |  | $ | 2.1 |  |  | $ | (91.7) |
Other comprehensive (loss) before reclassifications | (7.3) |  |  | — |  |  | (7.3) |
Net amount reclassified to net income (loss) | 0.4 |  |  | (0.1) |  |  | 0.3 |
Balance, December 31, 2018 | (100.7) |  |  | 2.0 |  |  | (98.7) |
Impact of ASU 2018-02* | (1.3) |  |  | — |  |  | (1.3) |
Other comprehensive (loss) before reclassifications | (12.7) |  |  | — |  |  | (12.7) |
Net amount reclassified to net income (loss) | 3.0 |  |  | (0.1) |  |  | 2.9 |
Balance, December 31, 2019 | (111.7) |  |  | 1.9 |  |  | (109.8) |
Other comprehensive income before reclassifications | (13.5) |  |  | — |  |  | (13.5) |
Net amount reclassified to net income (loss) | 4.6 |  |  | (0.1) |  | 4.5 |
Balance, December 31, 2020 | $ | (120.6) |  |  | $ | 1.8 |  |  | $ | (118.8) |
*ASU 2018-02. See Note 14. Income Taxes for further information regarding our adoption of ASU 2018-02.
Reclassification out of AOCI | Reclassifications out of AOCL were included in the consolidated statements of operations as follows:
AOCL Components |  | Location |  | 2020 |  | 2019 |  | 2018
Defined benefit plan and other postretirement liabilities |  | Cost of goods sold |  | $ | (4.7) |  |  | $ | (3.2) |  |  | $ | 2.8 |
|  | Selling, general and administrative expenses |  | (2.0) |  |  | (4.4) |  |  | (1.9) |
|  | Other operating expense, net |  | (1.1) |  |  | (1.0) |  |  | 1.2 |
|  | Income tax expense |  | (1.1) |  |  | (1.1) |  |  | (1.6) |
|  | Net of tax |  | $ | (8.9) |  |  | $ | (9.7) |  |  | $ | 0.5 |
Gain (loss) on financial instruments |  | Cost of goods sold |  | $ | (0.2) |  |  | $ | (0.2) |  |  | $ | (0.2) |
|  | Income tax benefit |  | 0.1 |  |  | 0.1 |  |  | 0.0 |
|  | Net of tax |  | $ | (0.1) |  |  | $ | (0.1) |  |  | $ | (0.2) |

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