Derivative Instruments - Balance Sheet Offsetting (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Cash collateral
Cash collateral posted	$ 16.0	$ 100.3
Cash collateral received	4.2
Offsetting derivative assets
Gross amount recognized on the balance sheet	41.1	18.0
Gross amount not offset on the balance sheet	(11.5)	(3.1)
Net amount	29.6	14.9
Cash collateral received	4.2
Offsetting derivative liabilities
Gross amount recognized on the balance sheet	13.9	106.4
Gross amount not offset on the balance sheet	(7.3)	(71.0)
Net amount	$ 6.6	35.4
Cash collateral posted		$ 67.9

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, and obligation to return cash collateral under master netting arrangements.

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