Summary Of Significant Accounting Policies Summary of Significant Accounting Policies (Voluntary Severance Incentive Program) (Details) (Employee Severance [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 employee
Employee Severance [Member]
Restructuring Reserve Disclosures [Line Items]
Severance Costs	$ 7.3
Restructuring and Related Cost, Number of Positions Eliminated	55