Business Segments (Details) (USD $)	3 Months Ended		9 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013	Jul. 31, 2012
Segment Reporting Information [Line Items]
Revenues from External Customers	$ 162,943,000	$ 161,123,000	$ 1,078,229,000	$ 941,395,000
Margin	97,000,000	86,460,000	512,480,000	478,647,000
Operations And Maintenance Expenses	62,985,000	59,262,000	184,024,000	178,214,000
Income From Equity Method Investments	3,652,000	3,290,000	23,244,000	21,234,000
Operating Income (Loss) Before Income Taxes	(2,973,000)	(6,681,000)	219,218,000	197,099,000
Income (Loss) Before Income Taxes	(5,137,000)	(7,457,000)	228,804,000	201,124,000
Number Of Operating Segments	2
Regulated Operation [Member]
Segment Reporting Information [Line Items]
Revenues from External Customers	162,943,000	161,123,000	1,078,229,000	941,395,000
Margin	97,000,000	86,460,000	512,480,000	478,647,000
Operations And Maintenance Expenses	62,950,000	59,248,000	183,869,000	178,155,000
Income From Equity Method Investments	0	0	0	0
Operating Income (Loss) Before Income Taxes	(2,856,000)	(6,595,000)	219,540,000	197,316,000
Income (Loss) Before Income Taxes	(8,673,000)	(10,662,000)	205,882,000	180,108,000
Non Utility Activities [Member]
Segment Reporting Information [Line Items]
Revenues from External Customers	0	0	0	0
Margin	0	0	0	0
Operations And Maintenance Expenses	35,000	14,000	155,000	59,000
Income From Equity Method Investments	3,652,000	3,290,000	23,244,000	21,234,000
Operating Income (Loss) Before Income Taxes	(117,000)	(86,000)	(322,000)	(217,000)
Income (Loss) Before Income Taxes	$ 3,536,000	$ 3,205,000	$ 22,922,000	$ 21,016,000