CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
OPERATING REVENUES
Utility		$ 731,865	$ 695,637	$ 594,346
Nonutility		2,183,244	1,572,980	1,286,559
Total operating revenues		2,915,109	2,268,617	1,880,905
Gas purchases:
Utility		276,005	258,687	205,034
Nonutility		1,990,832	1,436,740	1,139,301
Related parties		8,505	8,340	8,351
Operation and maintenance		266,919	226,356	208,421
Regulatory rider expenses		38,969	40,243	39,300
Depreciation and amortization		85,701	81,841	72,748
Energy and other taxes		52,102	49,366	40,215
Total operating expenses		2,719,033	2,101,573	1,713,370
OPERATING INCOME		196,076	167,044	167,535
Other income, net		16,853	14,437	9,196
Interest expense, net of capitalized interest		46,286	44,886	31,044
INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF AFFILIATES		166,643	136,595	145,687
Income tax (benefit) provision		(53,785)	18,343	23,530
Equity in earnings of affiliates		13,008	13,813	9,515
NET INCOME		$ 233,436	$ 132,065	$ 131,672
EARNINGS PER COMMON SHARE
Basic (in dollars per share)		$ 2.66	$ 1.53	$ 1.53
Diluted (in dollars per share)	[1]	$ 2.64	$ 1.52	$ 1.52
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (in shares)		87,689	86,321	85,884
Diluted (in shares)		88,315	87,144	86,731

[1] There were no anti-dilutive shares excluded from the calculation of diluted earnings per share for fiscal 2018, 2017 and 2016.