SIGNIFICANT ACCOUNTING POLICIES AND PRACTICES - (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Significant Accounting Policies And Practices [Line Items]
Discrete income tax deficiencies related as a component of the income tax provision						$ 200
Decrease in cash provided by operating activities						$ (13,106)	$ (69,750)	$ (52,891)
Increase in diluted shares	13,135,000	13,256,000	13,559,000	13,405,000	13,302,000	13,250,000	13,922,000	13,997,000
Minimum [Member]
Significant Accounting Policies And Practices [Line Items]
Estimated useful life of property and equipment						3 years
Maximum [Member]
Significant Accounting Policies And Practices [Line Items]
Estimated useful life of property and equipment						15 years
Software Development [Member]
Significant Accounting Policies And Practices [Line Items]
Estimated useful life of property and equipment						5 years
Accounting Standards Updates 2016-09 [Member]
Significant Accounting Policies And Practices [Line Items]
Decrease in cash provided by operating activities						$ 200
Increase in diluted shares						11,839
Adjustments for New Accounting Pronouncement [Member]
Significant Accounting Policies And Practices [Line Items]
Reduction in other assets amount						$ (100)
Southeast Catastrophe Consulting Company [Member]
Significant Accounting Policies And Practices [Line Items]
Noncontrolling ownership interest, percent						33.00%