FAIR VALUE MEASUREMENTS - Estimated Fair Value of Company's Debt Obligations, Using Level 2 Inputs, Compared to Carrying Value (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying value of debt obligations	$ 2,830.8	$ 2,778.7
Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of debt obligations	2,850.0	2,750.0
Carrying value of debt obligations	$ 2,830.0	$ 2,780.0