v3.5.0.2

Accounting for derivative instruments and hedging activities (Tables)

6 Months Ended

Jun. 30, 2016

Accounting for derivative instruments and hedging activities

Schedule of notional volumes of forecasted transactions

				June 30,		December 31,
		Units		2016		2015
Natural gas swaps		Natural Gas (Mmbtu)		5.7		2.8
Gas purchase agreements		Natural Gas (Gigajoules)		19.4		25.0
Interest rate swaps		Interest (US$)		532.3		302.3

Schedule of fair value of derivative instruments

		June 30, 2016
		Derivative			Derivative
		Assets			Liabilities
Derivative instruments designated as cash flow hedges:
Interest rate swaps current		$	—		$	1.0
Interest rate swaps long-term			—			3.2
Total derivative instruments designated as cash flow hedges			—			4.2
Derivative instruments not designated as cash flow hedges:
Interest rate swaps current			—			3.3
Interest rate swaps long-term			—			12.4
Natural gas swaps current			1.6			1.9
Natural gas swaps long-term			1.1			—
Gas purchase agreements current			—			17.4
Gas purchase agreements long-term			—			12.9
Total derivative instruments not designated as cash flow hedges			2.7			47.9
Total derivative instruments		$	2.7		$	52.1

		December 31, 2015
		Derivative			Derivative
		Assets			Liabilities
Derivative instruments designated as cash flow hedges:
Interest rate swaps current		$	—		$	1.0
Interest rate swaps long-term			—			2.7
Total derivative instruments designated as cash flow hedges			—			3.7
Derivative instruments not designated as cash flow hedges:
Interest rate swaps current			—			2.0
Interest rate swaps long-term			0.3			7.8
Natural gas swaps current			—			5.0
Natural gas swaps long-term			—			—
Gas purchase agreements current			—			28.7
Gas purchase agreements long-term			—			10.3
Total derivative instruments not designated as cash flow hedges			0.3			53.8
Total derivative instruments		$	0.3		$	57.5

Schedule of changes in OCI attributable to derivative financial instruments

		Interest Rate
Three Months Ended June 30, 2016		Swaps
Accumulated OCI balance at March 31, 2016		$	(0.1)
Change in fair value of cash flow hedges			(0.2)
Realized from OCI during the period			0.2
Accumulated OCI balance at June 30, 2016		$	(0.1)
		Interest Rate
Three Months Ended June 30, 2015		Swaps
Accumulated OCI balance at March 31, 2015		$	(0.2)
Change in fair value of cash flow hedges			0.2
Realized from OCI during the period			0.1
Accumulated OCI balance at June 30, 2015		$	0.1
		Interest Rate
Six Months Ended June 30, 2016		Swaps
Accumulated OCI balance at January 1, 2016		$	0.2
Change in fair value of cash flow hedges			(0.7)
Realized from OCI during the period			0.4
Accumulated OCI balance at June 30, 2016		$	(0.1)
		Interest Rate
Six Months Ended June 30, 2015		Swaps
Accumulated OCI balance at January 1, 2015		$	0.1
Change in fair value of cash flow hedges			(0.4)
Realized from OCI during the period			0.4
Accumulated OCI balance at June 30, 2015		$	0.1

Summary of realized loss (gain) for derivative instruments not designated as cash flow hedges

		Classification of loss (gain)		Three Months Ended June 30,						Six Months Ended June 30,
		recognized in income		2016			2015			2016			2015
Gas purchase agreements		Fuel		$	12.5		$	12.3			24.0		$	24.2
Natural gas swaps		Fuel			1.3			1.6			3.3			3.0
Interest rate swaps		Interest, net			1.1			1.0			1.7			1.9

Summary of the unrealized loss (gain) resulting from changes in the fair value of derivative financial instruments that are not designated as cash flow hedges

		Classification of gain (loss)		Three Months Ended June 30,						Six Months Ended June 30,
		recognized in income		2016			2015			2016			2015
Natural gas swaps		Change in fair value of derivatives		$	4.0		$	1.4		$	5.8		$	0.8
Gas purchase agreements		Change in fair value of derivatives			11.4			3.9			11.2			5.6
Interest rate swaps		Change in fair value of derivatives			(3.2)			1.5			(6.0)			(1.2)
				$	12.2		$	6.8		$	11.0		$	5.2

X

- Definition

Tabular disclosure for realized gains and losses on derivative instruments not designated as hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position.

+ References

No definition available.

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- Definition

Tabular disclosure for unrealized gains and losses on derivative instruments not designated as hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position.

+ References

No definition available.

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- Definition

Tabular disclosure of the effective portion of the gains and losses on derivative instruments designated (and non-derivative instruments) designated and qualifying in cash flow hedges and net investment hedges that was recognized in other comprehensive income (loss) during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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- Definition

Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

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- Definition

Tabular disclosure of the notional amounts of outstanding derivative positions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

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