UNIT-BASED COMPENSATION Table 3 (Details) - The 2000 LTIP [Member] - shares	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Performance awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (units)		47,646	29,633
Vesting		Performance awards vest 1/3 per year if certain performance measures are met, as defined in the award agreements.	Performance awards vest 1/3 per year if certain performance measures are met, as defined in the award agreements.
Restricted units, employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (units)		0	250,563
Vesting	1/5 per year	1/5 per year	1/5 per year
Restricted units, non-employee directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (units)		0	7,553
Vesting	1/3 per year	1/3 per year	1/3 per year

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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