NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Equity Offering (Details) - Class A Common Stock - Public Offering $ / shares in Units, shares in Millions, $ in Millions	Mar. 15, 2017 USD ($) $ / shares shares
Subsidiary, Sale of Stock [Line Items]
Sale of stock, number of shares issued (in shares) | shares	12.0
Sale of stock, price per share (USD per share) | $ / shares	$ 42.00
Sale of stock, consideration received on transaction | $	$ 487.9