SEGMENT INFORMATION

3 Months Ended

Mar. 31, 2017

Segment Reporting [Abstract]

SEGMENT INFORMATION

SEGMENT INFORMATION

At March 31, 2017, we reported six segments, which are described below.

• The Wisconsin segment includes the electric and natural gas utility operations of WE, WG, and WPS, including WE's and WPS's electric and natural gas operations in the state of Michigan that were transferred to UMERC effective January 1, 2017.

• The Illinois segment includes the natural gas utility and non-utility operations of PGL and NSG.

• The other states segment includes the natural gas utility and non-utility operations of MERC and MGU.

• The electric transmission segment includes our approximate 60% ownership interest in ATC, a for-profit, electric transmission company regulated by the FERC and certain state regulatory commissions.

• The We Power segment includes our nonregulated entity that owns and leases generating facilities to WE.

• The corporate and other segment includes the operations of the WEC Energy Group holding company, the Integrys holding company, the Peoples Energy, LLC holding company, Wispark LLC, Bostco, Wisvest, Wisconsin Energy Capital Corporation, WBS, WPS Power Development LLC, and ITF. The sale of ITF was completed in the first quarter of 2016. In the first quarter of 2017, we sold substantially all of the remaining assets of Bostco and in the second quarter of 2016, we sold certain assets of Wisvest. See Note 3, Dispositions, for more information on these sales.

All of our operations are located within the United States. The following tables show summarized financial information related to our reportable segments for the three months ended March 31, 2017 and 2016:

	Regulated Operations
(in millions)	Wisconsin		Illinois		Other States		Electric Transmission		Total Regulated Operations		We Power		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2017
External revenues	$	1,612.1	$	525.3	$	157.9	$	—	$	2,295.3	$	6.3	$	2.9		$	—		$	2,304.5
Intersegment revenues	—		—		—		—		—		109.0		—			(109.0		)	—
Other operation and maintenance	462.9		120.9		28.3		—		612.1		0.4		(1.6		)	(109.0		)	501.9
Depreciation and amortization	129.3		36.2		6.0		—		171.5		17.5		5.6			—			194.6
Operating income (loss)	332.3		155.4		33.4		—		521.1		97.4		(1.2		)	—			617.3
Equity in earnings of transmission affiliate	—		—		—		41.9		41.9		—		—			—			41.9
Interest expense	48.7		11.1		2.3		—		62.1		15.3		29.1			(1.8		)	104.7

	Regulated Operations
(in millions)	Wisconsin		Illinois		Other States		Electric Transmission		Total Regulated Operations		We Power		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2016
External revenues	$	1,579.8	$	448.5	$	148.4	$	—	$	2,176.7	$	6.2	$	11.9		$	—		$	2,194.8
Intersegment revenues	0.1		—		—		—		0.1		104.5		—			(104.6		)	—
Other operation and maintenance	491.3		117.9		30.0		—		639.2		0.4		(3.5		)	(104.6		)	531.5
Depreciation and amortization	122.9		32.8		5.1		—		160.8		17.0		10.1			—			187.9
Operating income (loss)	327.5		137.0		31.8		—		496.3		93.3		(0.3		)	—			589.3
Equity in earnings of transmission affiliate	—		—		—		38.5		38.5		—		—			—			38.5
Interest expense	44.5		9.7		2.5		—		56.7		15.6		31.3			(2.7		)	100.9