Segment Information Information By Segment (Details) - Geographical [Domain] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Revenues	$ 470,103	$ 489,353	$ 918,350	$ 964,148
Gross profit	118,571	163,041	256,770	317,576
Operating Income (Loss)	(3,951)	31,927	9,588	36,466
Total other income (expense)	(5,549)	(4,235)	(8,160)	(9,545)
Income Before Income Taxes	(9,500)	27,692	1,428	26,921
Electricity Operating Segment [Member]
Segment Reporting Information [Line Items]
Revenues	203,410	183,755	397,262	363,973
Gross profit	52,622	52,976	107,742	95,716
Operating Income (Loss)	3,904	(1,247)	6,300	(24,216)
Gas Operating Segment [Member]
Segment Reporting Information [Line Items]
Revenues	139,386	154,322	264,475	300,431
Gross profit	44,109	56,711	87,625	115,117
Operating Income (Loss)	14,742	24,329	28,334	50,053
Water Operating Segment [Member]
Segment Reporting Information [Line Items]
Revenues	127,307	151,276	256,613	299,744
Gross profit	21,840	53,354	61,403	106,743
Operating Income (Loss)	(11,511)	20,519	(3,414)	41,162
Corporate Unallocated [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ (11,086)	$ (11,674)	$ (21,632)	$ (30,533)