Fair Value Measurements (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Derivative instruments	$ 1.3	$ 2.2
Derivative instruments	7.2	1.3
Fair Value, Inputs, Level 1 [Member]
Derivative instruments	0.0	0.0
Derivative instruments	0.0	0.0
Fair Value, Inputs, Level 3 [Member]
Derivative instruments	0.0	0.0
Derivative instruments	$ 0.0	$ 0.0
Debentures With Put Feature [Member]
Debt instrument, maturity date range, start	Jan. 01, 2027
Debt instrument, maturity date range, end	Dec. 31, 2028

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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