SEGMENTS OF BUSINESS (Tables)

3 Months Ended

Mar. 31, 2015

Segment Reporting [Abstract]

Schedule of information related to reportable segments

The tables below present information related to our reportable segments:

	Regulated Operations											Nonutility and Nonregulated Operations
(Millions)	Natural Gas Utility			Electric Utility			Electric Transmission Investment		Total Regulated Operations			IES			Holding Company and Other			Reconciling Eliminations			Integrys Energy Group Consolidated
Three Months Ended
March 31, 2015
External revenues	$	839.5		$	295.8		$	—	$	1,135.3		$	—		$	27.9		$	—		$	1,163.2
Intersegment revenues	2.6			—			—		2.6			—			0.2			(2.8		)	—
Depreciation and amortization expense	40.6			25.0			—		65.6			—			9.2			(0.1		)	74.7
Earnings from equity method investments	—			—			17.0		17.0			—			0.5			—			17.5
Miscellaneous income	0.7			2.8			—		3.5			—			5.1			(2.0		)	6.6
Interest expense	14.3			10.9			—		25.2			—			15.0			(2.0		)	38.2
Provision (benefit) for income taxes	65.9			16.4			6.7		89.0			—			(10.1		)	—			78.9
Net income (loss) from continuing operations	97.8			28.6			10.3		136.7			—			(5.5		)	—			131.2
Discontinued operations	—			—			—		—			(0.8		)	(0.1		)	—			(0.9		)
Preferred stock dividends of subsidiary	(0.1		)	(0.7		)	—		(0.8		)	—			—			—			(0.8		)
Net income (loss) attributed to common shareholders	97.7			27.9			10.3		135.9			(0.8		)	(5.6		)	—			129.5

	Regulated Operations											Nonutility and Nonregulated Operations
(Millions)	Natural Gas Utility			Electric Utility			Electric Transmission Investment		Total Regulated Operations			IES		Holding Company and Other			Reconciling Eliminations			Integrys Energy Group Consolidated
Three Months Ended
March 31, 2014
External revenues	$	1,267.6		$	349.2		$	—	$	1,616.8		$	—	$	21.2		$	—		$	1,638.0
Intersegment revenues	4.4			—			—		4.4			—		0.4			(4.8		)	—
Depreciation and amortization expense	36.4			25.6			—		62.0			—		8.7			(0.1		)	70.6
Earnings from equity method investments	—			—			22.5		22.5			—		0.4			—			22.9
Miscellaneous income	0.3			3.5			—		3.8			—		5.3			(3.3		)	5.8
Interest expense	13.4			11.7			—		25.1			—		17.1			(3.3		)	38.9
Provision (benefit) for income taxes	66.7			18.1			8.8		93.6			—		(11.7		)	—			81.9
Net income (loss) from continuing operations	99.2			31.8			13.7		144.7			—		(4.5		)	—			140.2
Discontinued operations	—			—			—		—			13.0		(0.1		)	—			12.9
Preferred stock dividends of subsidiary	(0.1		)	(0.7		)	—		(0.8		)	—		—			—			(0.8		)
Noncontrolling interest in subsidiaries	—			—			—		—			—		0.1			—			0.1
Net income (loss) attributed to common shareholders	99.1			31.1			13.7		143.9			13.0		(4.5		)	—			152.4