FAIR VALUE MEASUREMENTS (Tables)

9 Months Ended

Sep. 30, 2017

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:



	September 30, 2017
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	2.8	$	3.7	$	—	$	6.5
Petroleum products contracts	1.0		—		—		1.0
FTRs	—		—		7.3		7.3
Coal contracts	—		0.9		—		0.9
Total derivative assets	$	3.8	$	4.6	$	7.3	$	15.7

Investments held in rabbi trust	$	113.5	$	—	$	—	$	113.5

Derivative liabilities
Natural gas contracts	$	1.5	$	2.5	$	—	$	4.0
Coal contracts	—		2.1		—		2.1
Total derivative liabilities	$	1.5	$	4.6	$	—	$	6.1



	December 31, 2016
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	10.1	$	24.2	$	—	$	34.3
Petroleum products contracts	0.2		—		—		0.2
FTRs	—		—		5.1		5.1
Coal contracts	—		2.0		—		2.0
Total derivative assets	$	10.3	$	26.2	$	5.1	$	41.6

Investments held in rabbi trust	$	103.9	$	—	$	—	$	103.9

Derivative liabilities
Natural gas contracts	$	0.2	$	0.2	$	—	$	0.4
Petroleum products contracts	0.1		—		—		0.1
Coal contracts	—		1.9		—		1.9
Total derivative liabilities	$	0.3	$	2.1	$	—	$	2.4

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 September 30						Nine Months Ended September 30
(in millions)	2017			2016			2017			2016
Balance at the beginning of the period	$	11.8		$	13.4		$	5.1		$	3.6
Realized and unrealized losses	—			—			—			(0.2		)
Purchases	—			—			13.8			15.2
Sales	—			—			—			(0.2		)
Settlements	(4.5		)	(4.2		)	(11.6		)	(9.2		)
Balance at the end of the period	$	7.3		$	9.2		$	7.3		$	9.2

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:



	September 30, 2017				December 31, 2016
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	29.6	$	30.4	$	28.8
Long-term debt, including current portion *	9,467.5		10,135.2		9,285.8		9,818.2


*	The carrying amount of long-term debt excludes capital lease obligations of $27.6 million and $29.6 million at September 30, 2017 and

December 31, 2016, respectively.