Segment Information (Tables)

9 Months Ended

Jun. 30, 2018

Segment Reporting [Abstract]

Schedule of Segment Information

				Reportable Segments
Three Months Ended June 30, 2018	Total			Gas Utility			Electric Utility
Revenues	$	159,934		$	138,597		$	21,337
Cost of sales — gas and purchased power	$	72,537		$	60,837		$	11,700
Depreciation and amortization	$	21,414		$	20,011		$	1,403
Operating income	$	3,914		$	2,628		$	1,286
Interest expense	$	10,003		$	9,829		$	174
(Loss) income before income taxes	$	(6,089	)	$	(7,201	)	$	1,112
Capital expenditures (including the effects of accruals)	$	79,704		$	76,546		$	3,158

			Reportable Segments
Three Months Ended June 30, 2017	Total		Gas Utility		Electric Utility
Revenues	$	146,692	$	127,849	$	18,843
Cost of sales — gas and purchased power	$	51,979	$	42,180	$	9,799
Depreciation and amortization	$	17,912	$	16,845	$	1,067
Operating income	$	27,671	$	25,628	$	2,043
Interest expense	$	10,128	$	9,601	$	527
Income before income taxes	$	17,543	$	16,027	$	1,516
Capital expenditures (including the effects of accruals)	$	79,088	$	75,836	$	3,252

			Reportable Segments
Nine Months Ended June 30, 2018	Total		Gas Utility		Electric Utility
Revenues	$	966,300	$	894,535	$	71,765
Cost of sales — gas and purchased power	$	481,613	$	440,726	$	40,887
Depreciation and amortization	$	62,926	$	58,787	$	4,139
Operating income	$	235,336	$	230,484	$	4,852
Interest expense	$	32,033	$	31,221	$	812
Income before income taxes	$	203,303	$	199,263	$	4,040
Capital expenditures (including the effects of accruals)	$	206,492	$	196,751	$	9,741
As of June 30, 2018
Total assets	$	3,194,025	$	3,008,441	$	185,584
Goodwill	$	182,145	$	182,145	$	—

			Reportable Segments
Nine Months Ended June 30, 2017	Total		Gas Utility		Electric Utility
Revenues	$	768,045	$	700,813	$	67,232
Cost of sales — gas and purchased power	$	325,991	$	288,610	$	37,381
Depreciation and amortization	$	53,002	$	49,378	$	3,624
Operating income	$	226,315	$	219,700	$	6,615
Interest expense	$	30,478	$	29,017	$	1,461
Income before income taxes	$	195,837	$	190,683	$	5,154
Capital expenditures (including the effects of accruals)	$	199,701	$	191,715	$	7,986
As of June 30, 2017
Total assets	$	2,904,532	$	2,743,035	$	161,497
Goodwill	$	182,145	$	182,145	$	—