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Commitments and Contingencies (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) location | Dec. 31, 2020 USD ($)
Commitments and Contingencies Disclosure [Abstract] |  |
Environmental liability | $ 51,000,000 | $ 54,000,000
Current environmental liability | $ 15,000,000 | $ 15,000,000
Known cleanup and remediation locations and projects | location | 100 |
Number of sites - representative sample | location | 17 |
Liability associated with those sites | $ 38,000,000 |
Environmental locations representative sample liability payout period, in years | 5 years |
Responsible locations with another party | location | 11 |
Self-insured injury/damage to third parties - and above, per occurrence | $ 75,000,000 |
Self-insured injury/damage to third party - up to | 800,000,000 |
Self-insured injury/damage to third parties - and above, per occurrence for specific perils | $ 1,100,000,000 |
Percentage of potential losses covered | 85.00% |
Self-insured NS owned property - and above, per occurrence | $ 75,000,000 |
Self-insured NS owned property - up to | $ 275,000,000 |

X
- Definition Number of known locations and projects of environmental loss contingencies. + References No definition available. + Details
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- Definition A representative sample of the total number of environmental locations and projects. + References No definition available. + Details
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- Definition Liability associated with the representative sample of environmental locations and projects. + References No definition available. + Details
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- Definition Number of years over which environmental liabilities are expected to be paid out. + References No definition available. + Details
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- Definition Number of locations the company or its subsidiaries in conjunction with other parties have been identified as potentially responsible parties by the Environmental Protection Agency (EPA). + References No definition available. + Details
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- Definition Amount above which the company is self-insured per occurrence for bodily injury and property damage to third parties. + References No definition available. + Details
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- Definition Amount above which the company is self-insured, per occurrence, for property owned or in the care, custody or control of the company. + References No definition available. + Details
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- Definition Amount up to which the company is self-insured, per occurrence, for property owned or in the care, custody or control of the company. + References No definition available. + Details
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- Definition Amount above which the company is self-insured per occurrence for bodily injury and property damage to third parties, for specific perils + References No definition available. + Details
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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- Definition Undiscounted amount of accrual for environmental loss contingency to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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