SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Percent of tax benefit received from increases in tax basis paid to stockholders	85.00%
Unrealized deferred tax asset	$ 325,405	$ 639,340
Realization period for deferred tax asset	10 years
Corporate Federal Tax Rate	21.00%