Condensed Consolidated Statements of Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues	$ 148,798	$ 143,644	$ 818,496	$ 770,087
Costs and expenses:
Cost of sales — gas, fuel and purchased power (excluding depreciation shown below)	64,332	62,701	415,394	412,377
Operating and administrative expenses	46,420	37,689	143,076	124,380
Operating and administrative expenses - related parties	1,940	2,107	6,757	7,013
Taxes other than income taxes	3,756	3,919	12,716	12,903
Depreciation	13,201	12,425	38,849	37,132
Amortization	832	826	2,467	2,292
Other income, net	(561)	(1,323)	(1,435)	(4,362)
Total costs and expenses	129,920	118,344	617,824	591,735
Operating income	18,878	25,300	200,672	178,352
Interest expense	9,690	10,575	29,587	31,859
Income before income taxes	9,188	14,725	171,085	146,493
Income taxes	3,815	6,265	70,641	57,494
Net income	$ 5,373	$ 8,460	$ 100,444	$ 88,999