LONG-TERM INCENTIVE AND RETIREMENT PLANS - Long-Term Incentive Plan and Unit Appreciation Right Activity (Paranthetical) (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Restricted phantom units \| 2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-Term incentive plan, fair value per unit	$ 6.72	$ 8.11
Common unit awards vested during the period, intrinsic values	$ 2.4	$ 0.4
Common unit awards outstanding, intrinsic values	2.4
Restricted phantom units \| 2004 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-Term incentive plan, fair value per unit		$ 9.70
Common unit awards outstanding, intrinsic values	$ 0.5
Restricted Units \| 2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-Term incentive plan, fair value per unit	$ 3.98

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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=116856206&loc=d3e5070-113901

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- Definition

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+ References

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