Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2013

Earnings Per Share [Abstract]

Schedule of Weighted Average Number of Shares

A reconciliation of the components of basic and diluted shares used in the EPS calculation follows:

	3 Months Ended		9 Months Ended		12 Months Ended
	September 30,		September 30,		September 30,
	2013	2012	2013	2012	2013	2012
	(in millions)
Weighted-average basic common shares outstanding	175.5	175.4	175.4	177.0	175.5	177.2
Potential number of shares issuable under the Company's LTSIP	—	1.1	0.7	1.1	0.6	1.1
Weighted-average diluted common shares outstanding	175.5	176.5	176.1	178.1	176.1	178.3