DERIVATIVE INSTRUMENTS - BALANCE SHEET OFFSETTING (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Cash collateral
Cash collateral received in margin accounts	$ 1.7
Cash collateral posted in margin accounts		$ 4.8
Offsetting derivative assets
Gross amount recognized on the balance sheet	7.4	2.1
Gross amount not offset on the balance sheet	(1.9)	(0.3)
Net amount	5.5	1.8
Cash collateral received	1.7
Offsetting derivative liabilities
Gross amount recognized on balance sheet	1.1	3.3
Gross amount not offset on balance sheet	(0.2)	(3.1)
Net amount	$ 0.9	0.2
Cash collateral posted		$ 2.8

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