Revenue Recognition - Future Minimum Payments Receivable (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) term
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total lease payments	$ 674
Less than 1 year	56
More than 5 years	394
Lease And Non-Lease Service Components
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total lease payments	617
Less than 1 year	109
Years 2 to 3	218
Years 4 to 5	218
More than 5 years	$ 72
Transportation Services Operating Leases Five Year Terms
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Initial term	10 years
Number of additional terms \| term	2
Additional term	5 years
Transportation Services Operating Leases Amended
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Additional term	14 months
Transportation Services Operating Leases One Year Terms
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Initial term	10 years
Number of additional terms \| term	10
Additional term	1 year
Transportation Services Operating Leases
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Initial term	10 years

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Lessor, Operating Lease, Payments to be Received, Four To Five Years

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Amount of lease payments to be received by lessor for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919396-209981

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Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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