OTHER CURRENT ASSETS (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Short-term portion of derivative assets (Note 21)	$ 44.1	$ 123.9
Regulatory assets (Note 6)	11.9	30.7
Prepaid expenses and other	36.2	18.4
Total other current assets	$ 92.2	$ 173.0