XML 116 R93.htm IDEA: XBRL DOCUMENT
v3.20.4

Commitments and Contingencies (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) location | Dec. 31, 2019 USD ($) location
Commitments and Contingencies Disclosure [Abstract] |  |
Environmental liability | $ 54,000,000 | $ 56,000,000
Current environmental liability | $ 15,000,000 | $ 15,000,000
Known cleanup and remediation locations and projects | location | 100 | 110
Number of sites - representative sample | location | 17 |
Liability associated with those sites | $ 40,000,000 |
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 for bodily injury and property damage to third parties above, for specific perils | 1,100,000,000 |
Self-insured NS owned property - and above, per occurrence | $ 75,000,000 |
Self-insured, percentage of potential losses covered | 85.00% |
Self-insured NS owned property - up to | $ 275,000,000 |
Purchase commitments | $ 1,100,000,000 |

X
- Definition Number of known locations and projects of environmental loss contingencies. + References No definition available. + Details
Name: | nsc_EnvironmentalCleanupLocations
Namespace Prefix: | nsc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition A representative sample of the total number of environmental locations and projects. + References No definition available. + Details
Name: | nsc_EnvironmentalLocationsRepresentativeSample
Namespace Prefix: | nsc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Liability associated with the representative sample of environmental locations and projects. + References No definition available. + Details
Name: | nsc_EnvironmentalLocationsRepresentativeSampleLiability
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of years over which environmental liabilities are expected to be paid out. + References No definition available. + Details
Name: | nsc_EnvironmentalLocationsRepresentativeSampleLiabilityPeriod
Namespace Prefix: | nsc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | nsc_EnvironmentalResponsiblePartyInConjunctionWithOtherParties
Namespace Prefix: | nsc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- 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
Name: | nsc_SelfInsuredForBodilyInjuryAndPropertyDamageToThirdPartiesAbove
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Self-Insured For Bodily Injury And Property Damage To Third Parties, Below, For Specific Perils + References No definition available. + Details
Name: | nsc_SelfInsuredForBodilyInjuryAndPropertyDamageToThirdPartiesBelowForSpecificPerils
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount up to which the company is self-insured per occurrence for bodily injury and property damage to third parties. + References No definition available. + Details
Name: | nsc_SelfInsuredForBodilyInjuryAndPropertyDamageToThirdPartiesUpTo
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | nsc_SelfInsuredForPropertyOwnedAbove
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | nsc_SelfInsuredForPropertyOwnedUpTo
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Self-Insured, Percentage Of Potential Losses Covered + References No definition available. + Details
Name: | nsc_SelfInsuredPercentageOfPotentialLossesCovered
Namespace Prefix: | nsc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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
Name: | us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesUndiscountedDueWithinOneYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition The minimum amount the entity agreed to spend under the long-term purchase commitment. + References No definition available. + Details
Name: | us-gaap_LongTermPurchaseCommitmentAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration