SEGMENTS OF BUSINESS (Tables)

6 Months Ended

Jun. 30, 2013

Segment Reporting [Abstract]

Schedule of information related to reportable segments

The table below presents information related to our reportable segments:

	Regulated Utilities
(Millions)	Electric Utility			Natural Gas Utility			Total Utility			Other		Reconciling Eliminations			WPS Consolidated
Three Months Ended June 30, 2013
External revenues	$	306.4		$	61.4		$	367.8		$	—	$	—		$	367.8
Intersegment revenues	—			2.4			2.4			0.3		(2.7		)	—
Depreciation and amortization expense	23.8			4.0			27.8			0.2		(0.2		)	27.8
Miscellaneous income	2.1			—			2.1			3.8		—			5.9
Interest expense	7.7			2.2			9.9			0.4		—			10.3
Provision for income taxes	14.5			0.3			14.8			1.0		—			15.8
Preferred stock dividend requirements	(0.6		)	(0.2		)	(0.8		)	—		—			(0.8		)
Net income attributed to common shareholder	23.1			0.3			23.4			2.5		—			25.9
	Regulated Utilities
(Millions)	Electric Utility			Natural Gas Utility			Total Utility			Other		Reconciling Eliminations			WPS Consolidated
Three Months Ended June 30, 2012
External revenues	$	292.5		$	45.0		$	337.5		$	—	$	—		$	337.5
Intersegment revenues	—			1.8			1.8			0.3		(2.1		)	—
Depreciation and amortization expense	20.2			3.8			24.0			0.2		(0.2		)	24.0
Miscellaneous income	0.5			—			0.5			4.0		—			4.5
Interest expense	8.1			1.9			10.0			0.6		—			10.6
Provision for income taxes	12.1			—			12.1			0.2		—			12.3
Preferred stock dividend requirements	(0.6		)	(0.2		)	(0.8		)	—		—			(0.8		)
Net income (loss) attributed to common shareholder	19.7			(0.7		)	19.0			3.6		—			22.6
	Regulated Utilities
(Millions)	Electric Utility			Natural Gas Utility			Total Utility			Other		Reconciling Eliminations			WPS Consolidated
Six Months Ended June 30, 2013
External revenues	$	614.3		$	186.9		$	801.2		$	—	$	—		$	801.2
Intersegment revenues	—			4.2			4.2			0.6		(4.8		)	—
Depreciation and amortization expense	43.3			7.9			51.2			0.3		(0.3		)	51.2
Miscellaneous income	3.7			0.1			3.8			7.1		—			10.9
Interest expense	15.9			4.3			20.2			1.0		—			21.2
Provision for income taxes	29.1			10.9			40.0			1.9		—			41.9
Preferred stock dividend requirements	(1.3		)	(0.3		)	(1.6		)	—		—			(1.6		)
Net income attributed to common shareholder	48.8			17.4			66.2			4.3		—			70.5
	Regulated Utilities
(Millions)	Electric Utility			Natural Gas Utility			Total Utility			Other		Reconciling Eliminations			WPS Consolidated
Six Months Ended June 30, 2012
External revenues	$	579.5		$	162.2		$	741.7		$	—	$	—		$	741.7
Intersegment revenues	—			3.1			3.1			0.7		(3.8		)	—
Depreciation and amortization expense	40.2			7.6			47.8			0.4		(0.3		)	47.9
Miscellaneous income	0.6			—			0.6			7.0		—			7.6
Interest expense	16.4			3.9			20.3			1.1		—			21.4
Provision for income taxes	21.5			10.7			32.2			1.5		—			33.7
Preferred stock dividend requirements	(1.3		)	(0.3		)	(1.6		)	—		—			(1.6		)
Net income attributed to common shareholder	42.6			17.3			59.9			4.8		—			64.7