Financial Instruments, Derivatives and Hedging Activities - FV (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Fair value
Fair value of assets and liabilities
Long-term debt	$ 2.0
Fair Value, Measurements, Recurring
Fair value of assets and liabilities
Available for sale securities	13.0	$ 11.0
Derivative assets	35.0	24.0
Derivative liabilities	37.0	26.0
Long-term debt	1,986.0	1,954.0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1
Fair value of assets and liabilities
Available for sale securities	13.0	11.0
Derivative assets	9.0	4.0
Derivative liabilities	10.0	6.0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2
Fair value of assets and liabilities
Derivative assets	26.0	20.0
Derivative liabilities	27.0	20.0
Long-term debt	$ 1,986.0	$ 1,954.0

Fair value, after the 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 not elected to be offset.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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