INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Foreign currency translation	$ 4.9	$ 9.1
Net operating loss carryforward and credits	138.6	102.3
Investment basis difference	96.2	121.6
Stock option expense	1.3	3.5
Hedging transactions	7.2	0.0
Marketable securities		0.1
Accrued reserves		0.1
Total deferred tax assets	248.2	236.7
Valuation allowance	(209.2)	(131.1)
Net deferred tax assets	39.0	105.6
Deferred tax liabilities:
Investment basis and reserve differences	145.7	121.3
Depreciation and amortization	2.8	65.0
Hedging transactions	0.0	5.4
Prepaid expenses and other	2.4	1.7
Capitalized interest	1.3	1.4
Total deferred tax liabilities	152.2	194.8
Deferred tax asset (liability), net	$ (113.2)	$ (89.2)