v3.19.3.a.u2

Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2019

Summary of significant accounting policies

Summary of derivative instruments not designated, treatment of changes in fair value and cash settlements

Derivative financial instrument		Classification of changes in fair value		Classification of cash settlements
Natural gas swaps		Changes in fair value of derivative instrument		Fuel expense
Fuel purchase agreements		Changes in fair value of derivative instrument		Fuel expense
Interest rate swaps		Changes in fair value of derivative instrument		Interest expense
Convertible debenture conversion option		Other expense (income), net		NA
Foreign currency forward contract		Foreign exchange loss (gain)		Foreign exchange loss (gain)

X

- References

No definition available.

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X

- Definition

Tabular disclosure of derivative instrument not designated or qualifying as hedging instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959

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