INCOME TAXES AND RELATED PAYMENTS - Income Tax Effects of Temporary Differences (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Examination [Line Items]
Investment in partnerships	$ 0	$ 210,678	$ 191,713
Equity-based compensation expense	0	5,535	3,537
Net operating losses	0	7,393	0
Other (1)	3,096	9,191	9,311
Total deferred tax assets	3,096	232,797	204,561
Total deferred tax liabilities	0	3,697	2,101
Net deferred tax assets before valuation allowance	3,096	229,100	202,460
Valuation allowance	0	0	0
Net deferred tax assets	3,096	$ 229,100	$ 202,460
Foreign Tax Authority
Income Tax Examination [Line Items]
Other (1)	$ 3,096