XML 79 R56.htm IDEA: XBRL DOCUMENT
v3.20.4

Investments - Narrative (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) railroad | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Schedule of Investments [Line Items] |  |  |
Access fees due 2021 | $ 41 |  |
Access fees due 2022 | $ 41 |  |
Number of railroads | railroad | 8 |  |
Impairment of investment | $ 99 | $ 0 | $ 0
Equity Method Investment, Nonconsolidated Investee, Other |  |  |
Schedule of Investments [Line Items] |  |  |
Impairment of investment | 99 |  |
Income (Loss) Due To Noncash Impairment Charges Against Equity Method Investment | 74 |  |
Shared Assets Areas CRC Lease |  |  |
Schedule of Investments [Line Items] |  |  |
Access fees due 2023 | 41 |  |
Access fees due 2024 | $ 17 |  |
Conrail Equity |  |  |
Schedule of Investments [Line Items] |  |  |
Equity method investment, ownership percentage | 58.00% | 58.00% |
Conrail Voting |  |  |
Schedule of Investments [Line Items] |  |  |
Equity method investment, ownership percentage | 50.00% | 50.00% |
Conrail Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Expenses from transactions with related party | $ 129 | $ 149 | 150
General and administrative support to Conrail | 6 |  |
Due to Conrail, current | 56 | 264 |
Due to Conrail, noncurrent | $ 534 | 280 |
Related Party Transaction, Rate | 1.31% |  |
Difference between investment in Conrail and share of Conrail's underlying net equity | $ 494 |  |
Equity in earnings of investee | 58 | 53 | 55
Due To Affiliated Current, Accounts Payable Converted to Noncurrent | $ 254 |  |
TTX Company |  |  |
Schedule of Investments [Line Items] |  |  |
Equity method investment, ownership percentage | 19.65% |  |
Equity in earnings of investee | $ 48 | 58 | 61
Purchased Services and Rent | TTX Company |  |  |
Schedule of Investments [Line Items] |  |  |
Expenses from transactions with related party | $ 250 | $ 244 | $ 262

X
- Definition Due To Affiliated Current, Accounts Payable Converted to Noncurrent + References No definition available. + Details
Name: | nsc_DueToAffiliatedCurrentAccountsPayableConvertedToNoncurrent
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Income (Loss) Due To Noncash Impairment Charges Against Equity Method Investment + References No definition available. + Details
Name: | nsc_IncomeLossDueToNoncashImpairmentChargesAgainstEquityMethodInvestment
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Long-Term Purchase Commitment, Future Access Due, Related Party Transaction, Year Four + References No definition available. + Details
Name: | nsc_LongTermPurchaseCommitmentFutureAccessDueRelatedPartyTransactionYearFour
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Long-term Purchase Commitment, Future Access Fees Due, Related Party Transaction, Year One + References No definition available. + Details
Name: | nsc_LongTermPurchaseCommitmentFutureAccessFeesDueRelatedPartyTransactionYearOne
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Long-term Purchase Commitment, Future Access Fees Due, Related Party Transaction, Year Three + References No definition available. + Details
Name: | nsc_LongTermPurchaseCommitmentFutureAccessFeesDueRelatedPartyTransactionYearThree
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Long-term Purchase Commitment, Future Access Fees Due, Related Party Transaction, Year Two + References No definition available. + Details
Name: | nsc_LongTermPurchaseCommitmentFutureAccessFeesDueRelatedPartyTransactionYearTwo
Namespace Prefix: | nsc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of Railroads Owning Joint Railcar Pooling Company + References No definition available. + Details
Name: | nsc_NumberOfRailroadsOwningJointRailcarPoolingCompany
Namespace Prefix: | nsc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(k)(1)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(a)(5)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(12)(b)(3)) -URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996 + Details
Name: | us-gaap_DueToAffiliateCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of receivables owed to an entity that is affiliated with the reporting entity by means of direct or indirect ownership, which are usually due after one year (or one business cycle, if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(12)(b)(3)) -URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(k)(1)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(23)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
Name: | us-gaap_DueToAffiliateNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentDifferenceBetweenCarryingAmountAndUnderlyingEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=121548190&loc=d3e32787-111569 + Details
Name: | us-gaap_EquityMethodInvestmentOtherThanTemporaryImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(f)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 + Details
Name: | us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
Name: | us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period. + References No definition available. + Details
Name: | us-gaap_RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties. + References No definition available. + Details
Name: | us-gaap_RelatedPartyTransactionRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis=us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_FixedMaturitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_EquityMethodInvesteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=nsc_AffiliateVotingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=nsc_ConrailIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=nsc_TTXCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=nsc_PurchasedservicesandrentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |