ORGANIZATION AND BASIS OF PRESENTATION Narrative 1 (Details)	Sep. 30, 2017 shares
Schedule of Equity Method Investments [Line Items]
Percent ownership in NuStar Energy	13.00%
Percent of incentive distribution rights issued by NuStar Energy	100.00%
Maximum percentage of cash distributed by NuStar Energy	23.00%
Common units of NuStar Energy	10,214,626

The ownership of limited partner common units in the investee accounted for under the equity method of accounting.

No definition available.

Name:	nsh_EquityMethodInvestmentOwnershipLimitedPartnerUnits
Namespace Prefix:	nsh_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Incentive Distribution Rights Percentage

+ References

No definition available.

+ Details

Name:	nsh_IncentiveDistributionRightsPercentage
Namespace Prefix:	nsh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum allowable percentage of cash distributed by equity method investee related to incentive distribution rights.

+ References

No definition available.

+ Details

Name:	nsh_IncentiveDistributionRightsPercentageMaximumAllowable
Namespace Prefix:	nsh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

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