Disclosures About Derivative Instruments and Hedging Activities Textual (Details) (USD $) In Thousands, unless otherwise specified												3 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2013 Electric Utility electric transmission congestion [Member] kWh	Dec. 31, 2012 Electric Utility electric transmission congestion [Member] kWh	Dec. 31, 2013 Gas Utility [Member] DTH	Dec. 31, 2012 Gas Utility [Member] DTH	Dec. 31, 2013 Electric Utility [Member] kWh	Dec. 31, 2012 Electric Utility [Member] kWh	Dec. 31, 2013 Interest Rate Protection Agreements [Member]	Dec. 31, 2012 Interest Rate Protection Agreements [Member]	Dec. 31, 2012 Interest Rate Swap [Member]
Disclosures About Derivative Instruments Hedging Activities (Textual) [Abstract]
Notional amount (in units)				117,900,000	118,200,000	9,700,000	13,000,000	324,400,000	482,300,000
Total Derivatives Liability	$ 3,344	$ 6,726	$ 39,664					$ (3,182)	$ (8,182)
Derivative Assets	2,058	43	4,760
Derivative Liabilities	3,272	6,677	39,453
Total Derivatives Assets	2,130	92	4,971
Underlying variable rate debt										0	173,000
Recorded loss amount included in Other Income, Net												0
Maximum length of time hedged in price risk cash flow hedges (in months)						9 months		11 months
Amount of net losses associated with interest rate hedges to be reclassified with interest rate hedges during the next 12 months	2,680
Restricted Cash in brokerage accounts	$ 0	$ 3,181	$ 2,106