Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

Name:	us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Gas And Oil Acreage [Line Items]
Cancelable service contracts expected period	1 year
Tax Accounting for Intra-entity Asset Transfers Other Than Inventory
Gas And Oil Acreage [Line Items]
Cumulative effect of new accounting pronouncement			$ 294
Accumulated Deficit \| Tax Accounting for Intra-entity Asset Transfers Other Than Inventory
Gas And Oil Acreage [Line Items]
Cumulative effect of new accounting pronouncement		$ 300	$ 294