ASSET RETIREMENT OBLIGATIONS (Tables)

12 Months Ended

Dec. 31, 2013

Asset Retirement Obligation Disclosure [Abstract]

Disclosure of changes in asset retirement obligations

The following table shows changes to our asset retirement obligations through December 31, 2013:

(Millions)	Utilities				Integrys Energy Services		Total
Asset retirement obligations at December 31, 2010	$	320.9			$	—	$	320.9
Accretion	17.1				—		17.1
Additions and revisions to estimated cash flows	64.4			*	0.5		64.9
Settlements	(5.7		)		—		(5.7		)
Asset retirement obligations at December 31, 2011	396.7				0.5		397.2
Accretion	20.3				0.1		20.4
Additions and revisions to estimated cash flows	(2.4		)		1.6		(0.8		)
Settlements	(5.6		)		—		(5.6		)
Asset retirement obligations at December 31, 2012	409.0				2.2		411.2
Accretion	20.8				0.1		20.9
Additions and revisions to estimated cash flows	70.1			*	0.5		70.6
Settlements	(11.2		)		—		(11.2		)
Asset retirement obligations at December 31, 2013	$	488.7			$	2.8	$	491.5

* Revisions were made to estimated cash flows related to asset retirement obligations primarily due to an increase in the weighted average cost to retire a foot of natural gas distribution pipe at PGL.