DERIVATIVE INSTRUMENTS - BALANCE SHEET OFFSETTING (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Cash collateral
Cash collateral posted	$ 14.0	$ 13.9
Cash collateral received	146.1	13.2
Offsetting derivative assets
Gross amount recognized on the balance sheet	219.1	120.0
Gross amount not offset on the balance sheet	(139.5)	(15.2)
Net amount	79.6	104.8
Collateral received	139.3	6.4
Offsetting derivative liabilities
Gross amount recognized on the balance sheet	1.4	15.1
Gross amount not offset on the balance sheet	(0.2)	(9.2)
Net amount	$ 1.2	5.9
Collateral posted		$ 0.4

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