Commitments and Contingencies (Details) - USD ($)	Sep. 01, 2016	Dec. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Clean-up costs accrued		$ 0	$ 0
Accrual for settlement of litigation			$ 2,300,000
Monthly lease payment	$ 400,000
Initial term of contract	10 years
Renewal term	1 year

Capital lease monthly payment.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Lessee Leasing Arrangement, Capital Lease, Renewal Term

+ References

No definition available.

+ Details

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- Definition

Lessee Leasing Arrangements, Capital Lease, Term of Contract

+ References

No definition available.

+ Details

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Namespace Prefix:	shlx_
Data Type:	xbrli:durationItemType
Balance Type:	na
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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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- Definition

Amount of costs recognized in the balance sheet for known or estimated future costs arising from requirements to perform activities to remediate one or more sites.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 25
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=39739230&loc=d3e11660-110855

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant