CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2011
OPERATING REVENUES
Utility	$ 787,987		$ 627,713		$ 971,724
Nonutility	2,410,081		1,621,210		2,037,485
Total operating revenues	3,198,068		2,248,923		3,009,209
OPERATING EXPENSES
Gas Purchases - Utility	406,185		268,459		534,363
Gas Purchases - Nonutility	2,306,038		1,572,949		2,016,208
Operation and maintenance	173,473		171,045		163,111
Regulatory rider expenses	48,417		40,350		51,246
Depreciation and amortization	47,310		41,643		34,370
Energy and other taxes	57,414		45,787		66,910
Total operating expenses	3,038,837		2,140,233		2,866,208
OPERATING INCOME	159,231		108,690		143,001
Other income	4,783		2,128		3,747
Interest expense, net of capitalized interest	23,979		20,844		19,623
INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF AFFILIATES	140,035		89,974		127,125
Income tax provision	35,575		7,729		37,665
Equity in earnings of affiliates	10,349		10,634		11,839
NET INCOME	$ 114,809		$ 92,879		$ 101,299
EARNINGS PER COMMON SHARE
BASIC (in usd per share)	$ 2.76		$ 2.24		$ 2.45
DILUTED (in usd per share)	$ 2.75	[1]	$ 2.23	[1]	$ 2.44	[1]
DIVIDENDS PER COMMON SHARE (in usd per share)	$ 1.62		$ 1.54		$ 1.44
WEIGHTED AVERAGE SHARES OUTSTANDING
BASIC (in shares)	41,658		41,527		41,359
DILUTED (in shares)	41,814		41,632		41,568

[1] There were no anti-dilutive shares excluded from the calculation of diluted earnings per share for fiscal 2013, 2012 and 2011.