v3.19.3.a.u2

Accounting for derivative instruments and hedging activities - FV by Bal Sht Loc (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair value of derivative instruments
Derivative Assets	$ 0.7	$ 4.5
Derivative Liabilities	27.9	19.9
Derivative instruments designated as cash flow hedges
Fair value of derivative instruments
Derivative Liabilities	1.5	1.4
Derivative instruments designated as cash flow hedges | Interest rate swaps | Current
Fair value of derivative instruments
Derivative Liabilities	0.4	0.4
Derivative instruments designated as cash flow hedges | Interest rate swaps | Long-term
Fair value of derivative instruments
Derivative Liabilities	1.1	1.0
Derivative instruments not designated as cash flow hedges
Fair value of derivative instruments
Derivative Assets	0.7	4.5
Derivative Liabilities	26.4	18.5
Derivative instruments not designated as cash flow hedges | Interest rate swaps | Current
Fair value of derivative instruments
Derivative Assets		4.2
Derivative Liabilities	1.9
Derivative instruments not designated as cash flow hedges | Interest rate swaps | Long-term
Fair value of derivative instruments
Derivative Assets		0.3
Derivative Liabilities	1.1
Derivative instruments not designated as cash flow hedges | Natural gas swaps | Current
Fair value of derivative instruments
Derivative Liabilities	1.9	0.1
Derivative instruments not designated as cash flow hedges | Natural gas swaps | Long-term
Fair value of derivative instruments
Derivative Liabilities	4.2	1.4
Derivative instruments not designated as cash flow hedges | Gas purchase agreements | Current
Fair value of derivative instruments
Derivative Assets	0.7
Derivative Liabilities	4.6	2.8
Derivative instruments not designated as cash flow hedges | Gas purchase agreements | Long-term
Fair value of derivative instruments
Derivative Liabilities	9.5	13.0
Derivative instruments not designated as cash flow hedges | Convertible Debentures | Current
Fair value of derivative instruments
Derivative Liabilities	$ 3.2	$ 1.2

X

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
-Section 50
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
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+ References

No definition available.

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