Derivatives - Gross and Net Fair Value of Derivative Assets and Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Offsetting of Derivative Assets
Gross Amounts of Recognized Assets	$ 238.7	$ 95.3
Net Amounts Presented in the Consolidated Balance Sheets	238.7	95.3
Derivatives Not Offset in the Consolidated Balance Sheets	(147.3)	(74.7)
Net Amounts	91.4	20.6
Derivatives that are not or may not be subject to master netting arrangement or similar agreement	162.5	109.2
Total	401.2	204.5
Offsetting of Derivative Liabilities
Gross Amounts of Recognized Liabilities	205.2	121.8
Net Amounts Presented in the Consolidated Balance Sheets	205.2	121.8
Derivatives Not Offset in the Consolidated Balance Sheets	(147.3)	(74.7)
Net Amounts	57.9	47.1
Derivatives that are not or may not be subject to master netting arrangement or similar agreement	118.3	37.7
Total	$ 323.5	$ 159.5

Fair value, before effects of master netting arrangements, of a 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. Includes assets not subject to a master netting arrangement and elected not to be offset.

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