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Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value Measured on a Recurring Basis - USD ($)
$ in Millions

Mar. 31, 2020

Dec. 31, 2019

Financial Assets

Investments in marketable securities

$ 54.6

$ 59.4

Derivative financial instruments

^[1]

1.2

7.9

Financial Liabilities

Affiliate equity repurchase obligations

^[2]

115.1

19.8

Derivative financial instruments

^[2]

1.2

1.0

Quoted Prices in Active Markets for Identical Assets (Level 1)

Financial Assets

Investments in marketable securities

23.9

24.4

Derivative financial instruments

^[1]

0.0

0.0

Financial Liabilities

Affiliate equity repurchase obligations

^[2]

0.0

0.0

Derivative financial instruments

^[2]

0.0

0.0

Significant Other Observable Inputs (Level 2)

Financial Assets

Investments in marketable securities

30.7

35.0

Derivative financial instruments

^[1]

1.2

7.9

Financial Liabilities

Affiliate equity repurchase obligations

^[2]

0.0

0.0

Derivative financial instruments

^[2]

1.2

1.0

Significant Unobservable Inputs (Level 3)

Financial Assets

Investments in marketable securities

0.0

0.0

Derivative financial instruments

^[1]

0.0

0.0

Financial Liabilities

Affiliate equity repurchase obligations

^[2]

115.1

19.8

Derivative financial instruments

^[2]

$ 0.0

$ 0.0

[1]	Amounts are presented within Other assets.
[2]	Amounts are presented within Other liabilities.

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