v3.10.0.1

Fair Value Measurements (Assets and Liabilities Reconciliation) (Schedule and Footnote) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance of net assets (liabilities) at January 1, 2018	$ 958.9
Gains included in net earnings (loss)
Realized and unrealized (gains) losses, net	(61.7)
Impact of ASU 2016-01	31.9
Additions	25.3
Dispositions	(12.1)
Final settlement of Sumitomo Collar	(7.4)
Transfers out of Level 3	(2.0)
Foreign currency translation adjustments, dividends and other, net	(7.4)
Balance of net assets (liabilities) at June 30, 2018	929.9
Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance of net assets (liabilities) at January 1, 2018	406.6
Gains included in net earnings (loss)
Realized and unrealized (gains) losses, net	4.4
Impact of ASU 2016-01	31.9
Additions	25.1
Dispositions	(12.1)
Final settlement of Sumitomo Collar	0.0
Transfers out of Level 3	(2.0)
Foreign currency translation adjustments, dividends and other, net	(6.9)
Balance of net assets (liabilities) at June 30, 2018	447.0
Cross-currency and interest rate derivative contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance of net assets (liabilities) at January 1, 2018	(3.2)
Gains included in net earnings (loss)
Realized and unrealized (gains) losses, net	(4.5)
Impact of ASU 2016-01	0.0
Additions	0.2
Dispositions	0.0
Final settlement of Sumitomo Collar	0.0
Transfers out of Level 3	0.0
Foreign currency translation adjustments, dividends and other, net	0.2
Balance of net assets (liabilities) at June 30, 2018	(7.3)
Equity-related derivative instruments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance of net assets (liabilities) at January 1, 2018	555.5
Gains included in net earnings (loss)
Realized and unrealized (gains) losses, net	(57.2)
Impact of ASU 2016-01	0.0
Additions	0.0
Dispositions	0.0
Final settlement of Sumitomo Collar	(7.4)
Transfers out of Level 3	0.0
Foreign currency translation adjustments, dividends and other, net	(0.7)
Balance of net assets (liabilities) at June 30, 2018	$ 490.2

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