Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014	Jul. 31, 2013
Statement of Comprehensive Income [Abstract]
Operating Revenues	$ 164,187	$ 162,943	$ 1,284,167	$ 1,078,229
Cost of Gas	59,340	65,943	706,285	565,749
Margin	104,847	97,000	577,882	512,480
Operating Expenses:
Operations and maintenance	68,605	62,950	199,437	183,869
Depreciation	29,960	28,599	87,947	82,168
General taxes	9,352	8,307	27,958	26,903
Utility income taxes	(6,324)	(3,447)	89,668	81,232
Total operating expenses	101,593	96,409	405,010	374,172
Operating Income	3,254	591	172,872	138,308
Other Income (Expense):
Income from equity method investments	5,043	3,652	29,345	23,244
Non-operating income	862	667	66	1,857
Non-operating expense	(1,660)	(897)	(3,711)	(2,355)
Income taxes	(1,718)	(603)	(10,050)	(8,152)
Total other income (expense)	2,527	2,819	15,650	14,594
Utility Interest Charges:
Interest on long-term debt	14,920	12,656	45,416	37,983
Allowance for borrowed funds used during construction	(4,543)	(7,507)	(15,960)	(25,758)
Other	2,748	554	6,298	1,257
Total utility interest charges	13,125	5,703	35,754	13,482
Net Income (Loss)	(7,344)	(2,293)	152,768	139,420
Other Comprehensive Income (Loss), net of tax:
Unrealized gain (loss) from hedging activities of equity method investments, net of tax of ($7) and ($21) for the three months ended July 31, 2014 and 2013, respectively, and $328 and $17 for the nine months ended July 31, 2014 and 2013, respectively	(10)	(36)	516	23
Reclassification adjustment of realized gain (loss) from hedging activities of equity method investments included in net income, net of tax of ($59) and ($33) for the three months ended July 31, 2014 and 2013, respectively, and ($199) and $30 for the nine months ended July 31, 2014 and 2013, respectively	(93)	(52)	(315)	45
Net current period benefit activities of equity method investments, net of tax of ($16) for the three months ended July 31, 2014 and ($16) for the nine months ended July 31, 2014	(25)		(25)
Total other comprehensive income (loss)	(128)	(88)	176	68
Comprehensive Income (Loss)	$ (7,472)	$ (2,381)	$ 152,944	$ 139,488
Average Shares of Common Stock:
Basic (in shares)	78,185	75,774	77,715	74,521
Diluted (in shares)	78,185	75,774	78,027	74,987
Earnings (Loss) Per Share of Common Stock:
Basic (usd per share)	$ (0.09)	$ (0.03)	$ 1.97	$ 1.87
Diluted (usd per share)	$ (0.09)	$ (0.03)	$ 1.96	$ 1.86