SUMMARY OF SIGNIFICANT ACCOUNTING AND BUSINESS POLICIES - Revenue Recognition (Details)	12 Months Ended
Dec. 31, 2018
Minimum
Deferred Revenue Arrangement [Line Items]
Revenue performance obligation expected satisfaction period	1
Maximum
Deferred Revenue Arrangement [Line Items]
Revenue performance obligation expected satisfaction period	2

Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130554-203045

Name:	us-gaap_RevenuePerformanceObligationDescriptionOfTiming
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration