FAIR VALUE MEASUREMENTS - Estimated Fair Value of Company'S Debt Obligations, Using Level 2 Inputs, Compared to Carrying Amount (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying value of debt obligations	$ 2,778.7	$ 2,747.2
Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of debt obligations	2,750.0	2,740.0
Carrying value of debt obligations	$ 2,780.0	$ 2,750.0