Summary Of Significant Accounting Policies (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Summary Of Significant Accounting Policies [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount		$ 2,300,000		$ 4,600,000
Investment portfolio percentage rated AA or higher			95.00%		97.00%
Sale and maturity of securities available for sale	8,100,000	44,500,000	15,130,000	71,492,000
Ecova [Member]
Summary Of Significant Accounting Policies [Line Items]
Owners percentage interest	79.00%		79.00%
Employee Severance [Member]
Summary Of Significant Accounting Policies [Line Items]
Severance costs					$ 7,300,000
Restructuring number of positions eliminated					55
Other Intangible Assets [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life			1 year
Other Intangible Assets [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life			12 years
Software and Software Development Costs [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life			3 years
Software and Software Development Costs [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life			5 years
Customer Relationships [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life			6 years
Customer Relationships [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life			12 years