Income Taxes (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended			1 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2013	Oct. 31, 2011 Tax Year 2007	Oct. 31, 2011 Tax Year 2008	Oct. 31, 2011 Tax Year 2009
Income Tax Contingency [Line Items]
Effective tax rate	27.00%	24.40%	26.90%	19.60%
Net benefit for a previously unrecognized position					$ 49.8
Expense for non-income based state taxes					10.3
Proposed deduction disallowance by tax authorities						$ 130.0	$ 130.0	$ 130.0