v3.8.0.1

UNIT-BASED COMPENSATION Table 2 - Restricted Unit Activity (Details) - $ / shares		12 Months Ended
	Mar. 01, 2016	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit-based awards, beginning balance (units)		793,097
Unit-based awards, transferred (units)	730,288
Unit-based awards, ending balance (units)		902,911	793,097
Restricted units, domestic employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit-based awards, beginning balance (units)		647,340	0
Unit-based awards, transferred (units)	586,524
Unit-based awards, granted (units)		307,009	246,070
Unit-based awards, vested (units)		(201,466)	(180,724)
Unit-based awards, forfeited (units)		(16,137)	(4,530)
Unit-based awards, ending balance (units)		736,746	647,340
Weighted-average grant date fair value, period start		$ 39.72	$ 0.00
Weighted average grant date fair value, transferred	$ 35.03
Weighted-average grant date fair value, granted		29.56	47.70
Weighted-average grant date fair value, vested		38.74	35.50
Weighted-average grant date fair value, forfeited		40.00	35.03
Weighted-average grant date fair value, period end		$ 35.95	$ 39.72
Restricted units, non-employee directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit-based awards, beginning balance (units)		18,134	0
Unit-based awards, transferred (units)	17,629
Unit-based awards, granted (units)		17,110	8,730
Unit-based awards, vested (units)		(8,147)	(8,225)
Unit-based awards, forfeited (units)		0	0
Unit-based awards, ending balance (units)		27,097	18,134
Restricted units, international employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit-based awards, beginning balance (units)		50,609	0
Unit-based awards, transferred (units)	49,121
Unit-based awards, granted (units)		24,533	20,107
Unit-based awards, vested (units)		(16,440)	(14,812)
Unit-based awards, forfeited (units)		(595)	(3,807)
Unit-based awards, ending balance (units)		58,107	50,609

X

- Definition

The number of unit-based payment awards transferred in the Employee Transfer.

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards transferred in the Employee Transfer.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ 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)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ 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)(i)-(ii)
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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

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