Related Parties and Affiliates - Schedule of Future Payments Due under Operating Leases (Details) $ in Millions	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
2020	$ 58
2021	54
2022	48
2023	39
2024	37
Thereafter	1,208
Total undiscounted operating lease payments	1,444
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
2020	29
2021	29
2022	29
2023	29
2024	22
Thereafter	0
Total undiscounted operating lease payments	$ 138

Amount of lessee's undiscounted obligation for lease payments for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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