Per unit of ownership amount of annual cash distributions declared to unitholder of limited partnership (LP).

No definition available.

Name:	snmp_DistributionMadeToLimitedPartnerAnnualDistributionsDeclaredPerUnit
Namespace Prefix:	snmp_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

+ Details

Name:	us-gaap_DistributionMadeToLimitedPartnerDistributionsDeclaredPerUnit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Fractional interest owned based on working interests or other economic arrangements of lease area on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas regardless of whether or not such area contains proved reserves.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1208
-Paragraph (b)

+ Details

Name:	us-gaap_GasAndOilAreaUndevelopedNet
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

+ Details

Name:	us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_RepaymentsOfLinesOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=snmp_IncreasedTariffRateForThroughputVolumesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PartnerTypeOfPartnersCapitalAccountAxis=snmp_LpCommonUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PartnerTypeOfPartnersCapitalAccountAxis=snmp_ClassBPreferredMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events (Details) - Subsequent event $ / shares in Units, $ in Millions	May 03, 2019 $ / shares	Apr. 23, 2019 USD ($)	Apr. 01, 2019 a
Subsequent Event [Line Items]
Payment of principal \| $		$ 2.0
Outstanding debt on credit facility \| $		$ 176.0
Increased tariff rate for throughput volumes
Subsequent Event [Line Items]
Net acres \| a			71,000
Common units
Subsequent Event [Line Items]
Distribution declared per unit	$ 0.1500
Annual distribution declared per unit	0.60
Class B preferred units
Subsequent Event [Line Items]
Distribution declared per unit	$ 0.28225