Financial Instruments - Effect of Derivative Instruments on Consolidated Statement of Operations and Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative	$ 1.8	$ (1.3)
Interest rate contracts \| Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI Into Income	(0.8)	(0.5)
Make-whole derivative liability \| Non-Operating Income (Expenses) – Net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives	0.0	69.8
Foreign exchange collar \| Non-Operating Income (Expenses) – Net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives	(2.5)	0.0
Foreign exchange forward contracts \| Non-Operating Income (Expenses) – Net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives	$ 2.9	$ 0.7

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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