Property Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Property, Plant and Equipment [Line Items]
Utilities	$ 2,427,810	$ 2,295,669
Distribution [Member]
Property, Plant and Equipment [Line Items]
Utilities	2,162,580	2,047,780
Transmission [Member]
Property, Plant and Equipment [Line Items]
Utilities	86,623	85,430
General and other, including contruction in process [Member]
Property, Plant and Equipment [Line Items]
Utilities	$ 178,607	$ 162,459