XML 31 R20.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Accumulated Other Comprehensive Income (Loss) | 12 Months Ended
--- | ---
Dec. 31, 2023
Equity [Abstract] |
Accumulated Other Comprehensive Income (Loss) | 11. Accumulated Other Comprehensive Income (Loss) The following table presents the changes in the accumulated balances for each component of AOCI (in millions of dollars):
|  | Year Ended December 31, |
|  | 2023 |  |  | 2022 |  |  | 2021 |
Defined Benefit Plans: |  |  |  |  |  |  |  |  |
Beginning balance |  | $ | 2.8 |  |  | $ | (21.4 | ) |  | $ | (19.8 | )
Actuarial gain arising during the period |  |  | 4.3 |  |  |  | 27.0 |  |  |  | 8.0 |
Less: income tax expense |  |  | (1.0 | ) |  |  | (6.5 | ) |  |  | (1.9 | )
Net actuarial gain arising during the period |  |  | 3.3 |  |  |  | 20.5 |  |  |  | 6.1 |
Prior service credit (cost) arising during the period |  |  | 2.2 |  |  |  | — |  |  |  | (14.0 | )
Less: income tax (expense) benefit |  |  | (0.5 | ) |  |  | — |  |  |  | 3.3 |
Net prior service credit (cost) arising during the period |  |  | 1.7 |  |  |  | — |  |  |  | (10.7 | )
Amortization of net actuarial (gain) loss 1 |  |  | (1.1 | ) |  |  | — |  |  |  | 0.4 |
Amortization of prior service cost 1 |  |  | 5.3 |  |  |  | 4.9 |  |  |  | 3.5 |
Less: income tax expense 2 |  |  | (1.0 | ) |  |  | (1.2 | ) |  |  | (0.9 | )
Net amortization reclassified from AOCI to Net income (loss) |  |  | 3.2 |  |  |  | 3.7 |  |  |  | 3.0 |
Other comprehensive income (loss), net of tax |  |  | 8.2 |  |  |  | 24.2 |  |  |  | (1.6 | )
Ending balance |  | $ | 11.0 |  |  | $ | 2.8 |  |  | $ | (21.4 | )
Cash Flow Hedges: |  |  |  |  |  |  |  |  |
Beginning balance |  | $ | 0.4 |  |  | $ | 17.7 |  |  | $ | 1.1 |
Unrealized (loss) gain on cash flow hedges |  |  | (10.7 | ) |  |  | (12.2 | ) |  |  | 63.6 |
Less: income tax benefit (expense) |  |  | 2.5 |  |  |  | 2.9 |  |  |  | (15.0 | )
Net unrealized (loss) gain on cash flow hedges |  |  | (8.2 | ) |  |  | (9.3 | ) |  |  | 48.6 |
Reclassification of unrealized loss (gain) upon settlement of cash flow hedges |  |  | 12.9 |  |  |  | (10.5 | ) |  |  | (41.9 | )
Less: income tax (expense) benefit 2 |  |  | (3.0 | ) |  |  | 2.5 |  |  |  | 9.9 |
Net loss (gain) reclassified from AOCI to Net income (loss) |  |  | 9.9 |  |  |  | (8.0 | ) |  |  | (32.0 | )
Other comprehensive income (loss), net of tax |  |  | 1.7 |  |  |  | (17.3 | ) |  |  | 16.6 |
Ending balance 3 |  | $ | 2.1 |  |  | $ | 0.4 |  |  | $ | 17.7 |
Total AOCI ending balance |  | $ | 13.1 |  |  | $ | 3.2 |  |  | $ | (3.7 | )
1. Amounts amortized out of AOCI related to pension and other postretirement benefits were included within Net periodic postretirement benefit cost (see Note 5). 2. Income tax amounts reclassified out of AOCI were included as a component of Income tax (provision) benefit. 3. As of December 31, 2023, we estimate a net mark-to-market gain before tax of $2.2 million in AOCI will be reclassified into Net income (loss) upon settlement within the next 12 months.

X
- Definition The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(21)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(23)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org//220/tableOfContent + Details
Name: | us-gaap_ComprehensiveIncomeNoteTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_EquityAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration