Basis of Presentation Basis of Presentation (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013
Accounting Changes and Error Corrections [Abstract]
Quantifying Misstatement in Current Year Financial Statements Adjustment Amount	$ 3.0	$ 2.6
Quantifying Misstatement in Current Year Financial Statements Amount Per Diluted Share	$ 0.04	$ 0.03