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Note 13 - Commitments and Contingencies (Details Textual) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 USD ($)
Sites Identified | 347
Sites Subject of Actions Taken by US Government | 32
Sites on Superfund National Priorities List | 20
Personal Injury [Member] |
Recorded Liability Related to Asserted Claims | 93.00%
Recorded Liability Related to Unasserted Claims | 7.00%
Personal Injury [Member] | Minimum [Member] |
Loss Contingency, Estimate of Possible Loss | $ 379
Personal Injury [Member] | Maximum [Member] |
Loss Contingency, Estimate of Possible Loss | $ 488

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- Definition Information on the percentage of recorded liability that relates to asserted claims. + References No definition available. + Details
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- Definition Sites identified at which Railroad is or may be liable for remediation costs associated with alleged contamination or for violations of environmental requirements. + References No definition available. + Details
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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-9 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-2 + Details
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