v3.4.0.3

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2016

Fair Value Disclosures [Abstract]

Fair value of assets and liabilities measured on a recurring basis, categorized by level within the fair value hierarchy

The following tables summarize our financial assets and liabilities that were accounted for at fair value on a recurring basis, categorized by level within the fair value hierarchy:

		March 31, 2016
(in millions)		Level 1				Level 2				Level 3				Total
Assets
Derivative assets
Natural gas contracts		$	0.6			$	1.7			$	—			$	2.3
FTRs		—				—				1.1				1.1
Petroleum products contracts		1.1				—				—				1.1
Coal contracts		—				1.6				—				1.6
Total derivative assets		$	1.7			$	3.3			$	1.1			$	6.1
Investments held in rabbi trust		$	41.7			$	—			$	—			$	41.7
Liabilities
Derivative liabilities
Natural gas contracts		$	8.8			$	21.7			$	—			$	30.5
Petroleum products contracts		3.8				—				—				3.8
Coal contracts		—				14.7				—				14.7
Total derivative liabilities		$	12.6			$	36.4			$	—			$	49.0

		December 31, 2015
(in millions)		Level 1				Level 2				Level 3				Total
Assets
Derivative assets
Natural gas contracts		$	1.6			$	1.5			$	—			$	3.1
FTRs		—				—				3.6				3.6
Petroleum products contracts		1.2				—				—				1.2
Coal contracts		—				2.0				—				2.0
Total derivative assets		$	2.8			$	3.5			$	3.6			$	9.9
Investments held in rabbi trust		$	39.8			$	—			$	—			$	39.8
Liabilities
Derivative liabilities
Natural gas contracts		$	16.5			$	25.3			$	—			$	41.8
Petroleum products contracts		4.9				—				—				4.9
Coal contracts		—				12.3				—				12.3
Total derivative liabilities		$	21.4			$	37.6			$	—			$	59.0

Reconciliation of changes in fair value of items categorized as level 3 measurements

The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy:

		Three Months Ended March 31
(in millions)		2016				2015
Balance at the beginning of the period		$	3.6			$	7.0
Realized and unrealized losses		(0.2		)		—
Sales		(0.1		)		—
Settlements		(2.2		)		(3.7		)
Balance at the end of the period		$	1.1			$	3.3

Schedule of carrying value and estimated fair value of financial instruments not recorded at fair value

The following table shows the financial instruments included on our balance sheets that are not recorded at fair value:

		March 31, 2016								December 31, 2015
(in millions)		Carrying Amount				Fair Value				Carrying Amount				Fair Value
Preferred stock		$	30.4			$	28.6			$	30.4			$	27.3
Long-term debt, including current portion *		$	9,055.4			$	9,790.5			$	9,221.9			$	9,681.0

* The carrying amount of long-term debt excludes capital lease obligations of $52.8 million and $59.9 million at March 31, 2016, and

December 31, 2015, respectively.

X

- Definition

Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13467-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6447952&loc=d3e13220-108610

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 30
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

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- Definition

Tabular disclosure of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) using recurring unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19279-110258

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- Definition

Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19190-110258

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