SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Cumulative Effect of Changes made to Balance Sheet for the Adoption of Topic 606 (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Assets
Property, plant and equipment, net	$ 1,887,759	$ 1,828,252	$ 1,795,129
Liabilities
Deferred revenue	10,778	10,088	4,000
Deferred revenue, noncurrent	38,119	35,528	12,707
Partners' Capital	932,236	1,088,644
Calculated under Revenue Guidance in Effect before Topic 606
Assets
Property, plant and equipment, net	1,852,126		1,795,129
Liabilities
Deferred revenue	4,071		4,000
Deferred revenue, noncurrent	11,133		12,707
Partners' Capital	921,898		$ 1,084,430
Accounting Standard Update 2014-09 \| Adjustments Due to Topic 606
Assets
Property, plant and equipment, net	35,633	33,123
Liabilities
Deferred revenue	6,707	6,088
Deferred revenue, noncurrent	26,986	22,821
Partners' Capital	$ 10,338	$ 4,214

General and limited partners capital account.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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