SEGMENT INFORMATION (Tables)

3 Months Ended

Mar. 31, 2019

Segment Reporting [Abstract]

Financial information of reportable segments

The following tables show summarized financial information related to our reportable segments for the three months ended March 31, 2019 and 2018:

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2019
External revenues	$	1,633.4	$	536.5	$	185.2	$	2,355.1	$	—	$	20.6	$	1.7		$	—		$	2,377.4
Intersegment revenues	—		—		—		—		—		107.2		—			(107.2		)	—
Other operation and maintenance	392.7		128.2		27.6		548.5		—		3.8		(1.0		)	(0.7		)	550.6
Depreciation and amortization	151.0		44.5		6.5		202.0		—		22.6		6.4			(4.6		)	226.4
Operating income (loss)	361.8		137.9		41.5		541.2		—		92.7		(3.9		)	(87.2		)	542.8
Equity in earnings of transmission affiliates	—		—		—		—		36.1		—		—			—			36.1
Interest expense	143.4		14.8		2.3		160.5		2.6		15.7		35.1			(89.5		)	124.4

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2018
External revenues	$	1,589.1	$	507.3	$	169.9	$	2,266.3	$	—	$	18.8	$	1.4		$	—		$	2,286.5
Intersegment revenues	—		—		—		—		—		99.3		—			(99.3		)	—
Other operation and maintenance	468.5		112.2		26.6		607.3		—		1.7		(0.3		)	(96.8		)	511.9
Depreciation and amortization	135.1		40.9		6.6		182.6		—		18.3		7.7			—			208.6
Operating income (loss)	273.7		147.6		36.2		457.5		—		93.0		(5.4		)	—			545.1
Equity in earnings of transmission affiliates	—		—		—		—		32.8		—		—			—			32.8
Interest expense	49.4		12.3		2.1		63.8		—		16.1		28.0			(1.2		)	106.7