Revenue Recognition - Future Minimum Payments Receivable (Details) $ in Millions	Dec. 31, 2019 USD ($)
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total lease payments	$ 831
Less than 1 year	56
More than 5 years	551
Transportation Services Operating Leases
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total lease payments	838
Less than 1 year	110
Years 2 to 3	219
Years 4 to 5	219
More than 5 years	$ 290

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

No definition available.

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Period Type:	instant

- Definition

Lessor, Operating Lease, Payments to be Received, Two To Three Years

+ References

No definition available.

+ Details

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Namespace Prefix:	shlx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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=119202524&loc=SL77919396-209981

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of lease payments to be received by lessor in next fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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- Definition

Amount of lease payments to be received by lessor after fifth fiscal year following latest statement of financial position date for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

+ Details

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- 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

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