Condensed Consolidated Statements of Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Revenues	$ 298,899	$ 273,797
Costs and expenses:
Cost of sales — gas, fuel and purchased power (excluding depreciation shown below)	151,865	138,277
Operating and administrative expenses	41,145	44,235
Operating and administrative expenses — related parties	1,843	1,805
Taxes other than income taxes	4,179	4,276
Depreciation	13,622	12,753
Amortization	828	818
Other income, net	(426)	(931)
Total costs and expenses	213,056	201,233
Operating income	85,843	72,564
Interest expense	8,797	10,077
Income before income taxes	77,046	62,487
Income taxes	31,760	25,675
Net income	$ 45,286	$ 36,812