CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
OPERATING REVENUES
Utility		$ 594,346	$ 781,970	$ 819,415
Nonutility		1,286,559	1,952,017	2,918,730
Total operating revenues		1,880,905	2,733,987	3,738,145
Gas purchases:
Utility		205,034	304,953	319,897
Nonutility		1,139,301	1,767,841	2,807,008
Related parties		8,351	12,851	12,620
Operation and maintenance		208,421	209,453	215,180
Regulatory rider expenses		39,300	75,779	72,164
Depreciation and amortization		72,748	61,399	52,742
Energy and other taxes		40,215	53,260	57,344
Total operating expenses		1,713,370	2,485,536	3,536,955
OPERATING INCOME		167,535	248,451	201,190
Other income, net		9,196	6,545	7,551
Interest expense, net of capitalized interest		31,044	27,721	25,463
INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF AFFILIATES		145,687	227,275	183,278
Income tax provision		23,530	59,724	51,840
Equity in earnings of affiliates		9,515	13,409	10,532
NET INCOME		$ 131,672	$ 180,960	$ 141,970
EARNINGS PER COMMON SHARE
Basic (in dollars per share)		$ 1.53	$ 2.12	$ 1.69
Diluted (in dollars per share)	[1]	1.52	2.10	1.67
DIVIDENDS DECLARED PER COMMON SHARE (in usd per share)		$ 0.975	$ 0.915	$ 0.855
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (in shares)		85,884	85,186	84,198
Diluted (in shares)		86,731	86,265	84,922

[1] There were no anti-dilutive shares excluded from the calculation of diluted earnings per share for fiscal 2016, 2015 and 2014.