SUMMARY OF SIGNIFICANT ACCOUNTING AND BUSINESS POLICIES - Impairment of Goodwill, Other Intangibles and Long-lived Assets (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Impairment of long-lived assets, excluding goodwill	$ 0	$ 0	$ 0