Restructuring Restructuring Expected Costs, Costs To-Date, Remaining Costs, and Costs During the Period - 2013 Projects (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Restructuring Cost and Reserve [Line Items]
Costs recognized during the period ended	$ 28,379	$ (5,054)	$ 32,777	$ 3,455
Employee severance costs
Restructuring Cost and Reserve [Line Items]
Costs recognized during the period ended			30,805
Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Costs recognized during the period ended			27
Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Costs recognized during the period ended			1,945
2013 Project [Member]
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			29,101
Costs recognized during the period ended			28,379
Remaining Costs to be Recognized at Period End			722
2013 Project [Member] | Employee severance costs
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			28,151
Costs recognized during the period ended			28,151
Remaining Costs to be Recognized at Period End			0
2013 Project [Member] | Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			250
Costs recognized during the period ended			0
Remaining Costs to be Recognized at Period End			250
2013 Project [Member] | Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			700
Costs recognized during the period ended			228
Remaining Costs to be Recognized at Period End			472
2013 Project [Member] | Energy Operating Segment [Member]
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			24,863
Costs recognized during the period ended			24,243
Remaining Costs to be Recognized at Period End			620
2013 Project [Member] | Water Operating Segment [Member]
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			2,395
Costs recognized during the period ended			2,337
Remaining Costs to be Recognized at Period End			58
2013 Project [Member] | Corporate Unallocated [Member]
Restructuring Cost and Reserve [Line Items]
Total expected costs at period end			1,843
Costs recognized during the period ended			1,799
Remaining Costs to be Recognized at Period End			$ 44