DERIVATIVE INSTRUMENTS - BALANCE SHEET OFFSETTING (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Cash collateral
Cash collateral posted	$ 10.5	$ 18.9
Cash collateral received	134.1
Offsetting derivative assets
Gross amount recognized on the balance sheet	270.1	17.9
Gross amount not offset on the balance sheet	(134.9)	(6.9)
Net amount	135.2	11.0
Collateral received	133.6
Offsetting derivative liabilities
Gross amount recognized on the balance sheet	22.3	22.1
Gross amount not offset on the balance sheet	(1.3)	(7.7)
Net amount	$ 21.0	14.4
Collateral posted		$ 0.8

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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