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Commitments and Contingencies - Additional Information (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) facility | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Contingencies And Commitments [Line Items] |  |  |
Environmental Loss Contingency, Current, Statement of Financial Position [Extensible Enumeration] | Accrued liabilities – other | Accrued liabilities – other |
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration] | Environmental Liabilities | Environmental Liabilities |
Environmental Remediation Expense, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other – net | Other – net | Other – net
Environmental Matters |  |  |
Contingencies And Commitments [Line Items] |  |  |
Pretax charge to comply U.S. federal, state and local environmental control and protection regulations | $ 20.0 | $ 20.0 | $ 17.5
Capital expenditure to comply environmental regulations | 0.7 | 1.6 | $ 3.1
Environmental reserves | 101.1 | 101.8 |
Environmental reserves included in current liabilities | $ 10.6 | 10.8 |
Government Operations | Environmental Matters |  |  |
Contingencies And Commitments [Line Items] |  |  |
Number of facilities | facility | 2 |  |
Financial assurance to pay expected cost of decommissioning | $ 68.1 | 68.1 |
Commercial Operations | Environmental Matters |  |  |
Contingencies And Commitments [Line Items] |  |  |
Financial assurance to pay expected cost of decommissioning | $ 44.3 | $ 43.3 |

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481931/410-30-50-10 Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Subparagraph (d)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481931/410-30-50-10 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 16 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481899/410-30-55-16 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480102/450-20-S99-1 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481931/410-30-50-7 + Details
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