Segment Information (Tables)

12 Months Ended

Sep. 30, 2016

Segment Reporting [Abstract]

Segment Information

Financial information by business segment follows:

	Total		Gas Utility		Electric Utility		Other
2016
Revenues	$	768,484	$	677,387	$	91,097
Cost of sales	$	289,786	$	239,163	$	50,623
Depreciation and amortization	$	67,303	$	62,451	$	4,852
Operating income	$	200,901	$	189,412	$	11,489
Interest expense	$	37,630	$	35,786	$	1,844
Income before income taxes	$	163,271	$	153,626	$	9,645
Total assets	$	2,743,091	$	2,570,297	$	172,794
Goodwill	$	182,145	$	182,145	$	—
Capital expenditures	$	262,503	$	251,261	$	11,242
2015
Revenues	$	1,041,581	$	933,080	$	107,577	$	924
Cost of sales	$	510,784	$	448,617	$	62,167	$	—
Depreciation and amortization	$	63,590	$	58,974	$	4,616	$	—
Operating income	$	241,667	$	226,485	$	14,153	$	1,029
Interest expense	$	41,128	$	39,112	$	2,016	$	—
Income before income taxes	$	200,539	$	187,373	$	12,137	$	1,029
Total assets	$	2,505,984	$	2,360,156	$	145,828	$	—
Goodwill	$	182,145	$	182,145	$	—	$	—
Capital expenditures	$	197,684	$	189,671	$	8,013	$	—
2014
Revenues	$	1,086,889	$	977,333	$	108,072	$	1,484
Cost of sales	$	562,942	$	496,762	$	66,180	$	—
Depreciation and amortization	$	59,219	$	54,816	$	4,403	$	—
Operating income	$	246,400	$	236,219	$	9,668	$	513
Interest expense	$	38,471	$	36,602	$	1,869	$	—
Income before income taxes	$	207,929	$	199,617	$	7,799	$	513
Total assets	$	2,352,143	$	2,211,618	$	140,525	$	—
Goodwill	$	182,145	$	182,145	$	—	$	—
Capital expenditures	$	164,180	$	156,425	$	7,755	$	—