Goodwill (Tables)

12 Months Ended

Dec. 31, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of changes to goodwill balances by segment

The following table shows changes to our goodwill balances by segment during the years ended December 31, 2016 and 2015:

	Wisconsin					Illinois				Other States				Total
(in millions)	2016			2015		2016		2015		2016		2015		2016		2015
Goodwill balance as of January 1	$	2,109.5		$	441.9	$	731.2	$	—	$	182.8	$	—	$	3,023.5	$	441.9
Adjustment to Integrys purchase price allocation	(5.2		)	—		27.5		—		0.4		—		22.7		—
Acquisition of Integrys	—			1,667.6		—		731.2		—		182.8		—		2,581.6
Goodwill balance as of December 31 *	$	2,104.3		$	2,109.5	$	758.7	$	731.2	$	183.2	$	182.8	$	3,046.2	$	3,023.5

* We had no accumulated impairment losses related to our goodwill as of December 31, 2016.