SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Summary of Impact of Topic 606 Adoption on Unaudited Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Assets
Accounts receivable	$ 85,458
Other noncurrent assets	18,566		$ 13,565
Property, plant and equipment, net	1,911,630	$ 1,828,252	1,795,129
Liabilities
Deferred revenue	11,152	10,088	4,000
Deferred revenue, noncurrent	39,624	35,528	12,707
Partners' Capital	939,293	1,088,644
Balances Without Adoption of Topic 606
Assets
Accounts receivable	76,656
Other noncurrent assets	12,566
Property, plant and equipment, net	1,874,388		1,795,129
Liabilities
Deferred revenue	4,071		4,000
Deferred revenue, noncurrent	10,065		12,707
Partners' Capital	923,889		$ 1,084,430
Accounting Standard Update 2014-09 \| Effect of Change Increase / (Decrease)
Assets
Accounts receivable	8,802
Other noncurrent assets	6,000
Property, plant and equipment, net	37,242	33,123
Liabilities
Deferred revenue	7,081	6,088
Deferred revenue, noncurrent	29,559	22,821
Partners' Capital	$ 15,404	$ 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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