Goodwill and Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2012

Change In Carrying Amount Of Goodwill

	Nine Months  Ended September 30, 2012		Year Ended December 31, 2011
	(Millions)
Beginning of period	$	153.8	$	151.2
Acquisitions		—		2.6
End of period	$	153.8	$	153.8

Schedule Of Intangible Assets

	September 30, 2012			December 31, 2011
	(Millions)
Gross carrying amount	$	164.3		$	164.3
Accumulated amortization		(25.3	)		(19.0	)
Intangible assets, net	$	139.0		$	145.3

Estimated Future Amortization For Intangible Assets

	Estimated Future Amortization
	(Millions)
Remainder of 2012	$	2.1
2013		8.4
2014		8.4
2015		8.4
2016		8.4
Thereafter		103.3
Total	$	139.0