Redeemable Noncontrolling Interests And Subsidiary Acquisitions Redeemable Noncontrolling Interests And Subsidiary Acquisitions (LPB Acquisition) (Details) (USD $)	9 Months Ended		0 Months Ended	1 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Jan. 31, 2012 LPB Energy Management [Member]	Jan. 31, 2012 LPB Energy Management [Member]	Sep. 30, 2013 Ecova [Member]	Sep. 30, 2013 Business Acquisition, Additional Payment Due in Year Two [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 50,600,000
Borrowed Funds			25,000,000	25,000,000
Proceeds from Issuance of Common Stock	4,479,000	28,699,000		20,000,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High						1,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Contingent Liability					$ 200,000