National Fuel Gas (NFG) 10-Q 9 May 14 2014 Q2 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	6 Months Ended
	Mar. 31, 2014	Apr. 30, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Entity Registrant Name	'NATIONAL FUEL GAS CO	'
Entity Central Index Key	'0000070145	'
Current Fiscal Year End Date	'--09-30	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	84,008,346
Trading Symbol	'nfg	'

Consolidated_Statements_Of_Inc

Consolidated Statements Of Income And Earnings Reinvested In The Business (Unaudited) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
INCOME	'	'	'	'
Operating Revenues	$756,242	$597,826	$1,306,314	$1,050,680
Operating Expenses	'	'	'	'
Purchased Gas	322,772	209,817	490,378	331,735
Operation and Maintenance	137,716	122,303	245,562	230,035
Property, Franchise and Other Taxes	25,704	22,685	46,630	42,348
Depreciation, Depletion and Amortization	89,975	80,030	183,089	152,361
Total Operating Expenses	576,167	434,835	965,659	756,479
Operating Income	180,075	162,991	340,655	294,201
Other Income (Expense):	'	'	'	'
Interest Income	249	140	951	1,526
Other Income	5,123	1,087	5,352	2,501
Interest Expense on Long-Term Debt	-22,766	-22,786	-45,651	-44,234
Other Interest Expense	-1,375	-526	-2,324	-1,595
Income Before Income Taxes	161,306	140,906	298,983	252,399
Income Tax Expense	66,095	55,186	121,520	98,735
Net Income Available for Common Stock	95,211	85,720	177,463	153,664
EARNINGS REINVESTED IN THE BUSINESS	'	'	'	'
Balance at Beginning of Period	1,493,466	1,343,765	1,442,617	1,306,284
Beginning Retained Earnings Unappropriated And Current Period Net Income Loss	1,588,677	1,429,485	1,620,080	1,459,948
Dividends on Common Stock	-31,493	-30,486	-62,896	-60,949
Balance at March 31	$1,557,184	$1,398,999	$1,557,184	$1,398,999
Earnings Per Common Share, Basic:	'	'	'	'
Net Income Available for Common Stock (in dollars per share)	$1.14	$1.03	$2.12	$1.84
Earnings Per Common Share, Diluted:	'	'	'	'
Net Income Available for Common Stock (in dollars per share)	$1.12	$1.02	$2.09	$1.83
Weighted Average Common Shares Outstanding:	'	'	'	'
Used in Basic Calculation (shares)	83,856,120	83,498,508	83,781,085	83,443,805
Used in Diluted Calculation (shares)	84,837,123	84,159,734	84,787,610	84,127,705
Dividends Per Common Share:	'	'	'	'
Dividends Declared (in dollars per share)	$0.38	$0.37	$0.75	$0.73

Consolidated_Statements_Of_Com

Consolidated Statements Of Comprehensive Income (Unaudited) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net Income Available for Common Stock	$95,211	$85,720	$177,463	$153,664
Other Comprehensive Income (Loss), Before Tax:	'	'	'	'
Unrealized Gain (Loss) on Securities Available for Sale Arising During the Period	622	1,983	3,120	2,773
Unrealized Gain (Loss) on Derivative Financial Instruments Arising During the Period	-67,461	-47,350	-64,682	-12,001
Reclassification Adjustment for Realized (Gains) Losses on Derivative Financial Instruments in Net Income	26,640	-10,503	16,457	-22,088
Other Comprehensive Income (Loss), Before Tax	-40,199	-55,870	-45,105	-31,316
Income Tax Expense (Benefit) Related to Unrealized Gain (Loss) on Securities Available for Sale Arising During the Period	231	741	1,156	1,037
Income Tax Expense (Benefit) Related to Unrealized Gain (Loss) on Derivative Financial Instruments Arising During the Period	-28,583	-19,813	-27,312	-5,076
Reclassification Adjustment for Income Tax Benefit (Expense) on Realized Losses (Gains) from Derivative Financial Instruments in Net Income	11,170	-4,419	6,872	-9,274
Income Taxes – Net	-17,182	-23,491	-19,284	-13,313
Other Comprehensive Income (Loss)	-23,017	-32,379	-25,821	-18,003
Comprehensive Income	$72,194	$53,341	$151,642	$135,661

Consolidated_Balance_Sheets_Un

Consolidated Balance Sheets (Unaudited) (USD $)	Mar. 31, 2014		Sep. 30, 2013
In Thousands, unless otherwise specified
ASSETS	'		'
Property, Plant and Equipment	$7,689,518		$7,313,203
Less - Accumulated Depreciation, Depletion and Amortization	2,325,636		2,161,477
Property, Plant and Equipment, Net, Total	5,363,882		5,151,726
Current Assets	'		'
Cash and Temporary Cash Investments	150,864		64,858
Hedging Collateral Deposits	0	[1]	1,094	[1]
Receivables – Net of Allowance for Uncollectible Accounts of $38,935 and $27,144 Respectively	267,512		133,182
Unbilled Revenue	83,378		19,483
Gas Stored Underground	3,176		51,484
Materials and Supplies - at average cost	25,551		29,904
Unrecovered Purchased Gas Costs	1,825		12,408
Other Current Assets	54,903		56,905
Deferred Income Taxes	39,650		79,359
Total Current Assets	626,859		448,677
Other Assets	'		'
Recoverable Future Taxes	161,258		163,355
Unamortized Debt Expense	15,478		16,645
Other Regulatory Assets	244,486		252,568
Deferred Charges	9,050		9,382
Other Investments	85,825		96,308
Goodwill	5,476		5,476
Prepaid Post-Retirement Benefit Costs	28,366		22,774
Fair Value of Derivative Financial Instruments	25,777		48,989
Other	738		2,447
Total Other Assets	576,454		617,944
Total Assets	6,567,195		6,218,347
Capitalization:	'		'
Common Stock, $1 Par Value Authorized - 200,000,000 Shares; Issued and Outstanding - 83,980,596 Shares and 83,661,969 Shares, Respectively	83,981		83,662
Paid in Capital	703,422		687,684
Earnings Reinvested in the Business	1,557,184		1,442,617
Accumulated Other Comprehensive Loss	-45,055		-19,234
Total Comprehensive Shareholders’ Equity	2,299,532		2,194,729
Long-Term Debt, Net of Current Portion	1,649,000		1,649,000
Total Capitalization	3,948,532		3,843,729
Current and Accrued Liabilities	'		'
Notes Payable to Banks and Commercial Paper	0		0
Current Portion of Long-Term Debt	0		0
Accounts Payable	153,147		105,283
Amounts Payable to Customers	24,665		12,828
Dividends Payable	31,493		31,373
Interest Payable on Long-Term Debt	29,960		29,960
Customer Advances	81		21,959
Customer Security Deposits	15,581		16,183
Other Accruals and Current Liabilities	235,900		83,946
Fair Value of Derivative Financial Instruments	22,236		639
Total Current and Accrued Liabilities	513,063		302,171
Deferred Credits	'		'
Deferred Income Taxes	1,352,731		1,347,007
Taxes Refundable to Customers	90,779		85,655
Unamortized Investment Tax Credit	1,361		1,579
Cost of Removal Regulatory Liability	165,138		157,622
Other Regulatory Liabilities	94,000		61,549
Pension and Other Post-Retirement Liabilities	145,085		158,014
Asset Retirement Obligations	120,884		119,511
Other Deferred Credits	135,622		141,510
Total Deferred Credits	2,105,600		2,072,447
Commitments and Contingencies	0		0
Total Capitalization and Liabilities	$6,567,195		$6,218,347
[1]	Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2014	Sep. 30, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Receivables, Allowance for Uncollectible Accounts	$38,935	$27,144
Common Stock, Par Value	$1	$1
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares Issued	83,980,596	83,661,969
Common Stock, Shares Outstanding	83,980,596	83,661,969

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (Unaudited) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
OPERATING ACTIVITIES	'	'
Net Income Available for Common Stock	$177,463	$153,664
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:	'	'
Depreciation, Depletion and Amortization	183,089	152,361
Deferred Income Taxes	71,939	102,557
Excess Tax Benefits Associated with Stock-Based Compensation Awards	-3,149	0
Stock-Based Compensation	8,045	6,596
Other	-118	8,013
Change in:	'	'
Hedging Collateral Deposits	1,094	-386
Receivables and Unbilled Revenue	-198,277	-109,403
Gas Stored Underground and Materials and Supplies	52,661	32,391
Unrecovered Purchased Gas Costs	10,583	0
Other Current Assets	-443	4,389
Accounts Payable	69,379	20,456
Amounts Payable to Customers	11,837	-1,725
Customer Advances	-21,878	-23,910
Customer Security Deposits	-602	-804
Other Accruals and Current Liabilities	102,222	39,273
Other Assets	23,445	-6,200
Other Liabilities	15,946	-10,417
Net Cash Provided by Operating Activities	503,236	366,855
INVESTING ACTIVITIES	'	'
Capital Expenditures	-367,393	-339,737
Other	4,927	-3,445
Net Cash Used in Investing Activities	-362,466	-343,182
Financing Activities	'	'
Changes in Notes Payable to Banks and Commercial Paper	0	-171,000
Excess Tax Benefits Associated with Stock-Based Compensation Awards	3,149	0
Net Proceeds from Issuance of Long-Term Debt	0	495,415
Reduction of Long-Term Debt	0	-250,000
Dividends Paid on Common Stock	-62,776	-60,879
Net Proceeds from Issuance of Common Stock	4,863	710
Net Cash Provided by (Used in) Financing Activities	-54,764	14,246
Net Increase in Cash and Temporary Cash Investments	86,006	37,919
Cash and Temporary Cash Investments at October 1	64,858	74,494
Cash and Temporary Cash Investments at March 31	150,864	112,413
Supplemental Disclosure of Cash Flow Information, Non-Cash Investing Activities:	'	'
Non-Cash Capital Expenditures	$109,355	$77,093

Summary_Of_Significant_Account

Summary Of Significant Accounting Policies	6 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Summary Of Significant Accounting Policies	'
	Summary of Significant Accounting Policies
	Principles of Consolidation.  The Company consolidates all entities in which it has a controlling financial interest.  All significant intercompany balances and transactions are eliminated.
	The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.  Actual results could differ from those estimates.
	Reclassifications.  Certain prior year amounts have been reclassified to conform with current year presentation.
	Earnings for Interim Periods.  The Company, in its opinion, has included all adjustments (which consist of only normally recurring adjustments, unless otherwise disclosed in this Form 10-Q) that are necessary for a fair statement of the results of operations for the reported periods. The consolidated financial statements and notes thereto, included herein, should be read in conjunction with the financial statements and notes for the years ended September 30, 2013, 2012 and 2011 that are included in the Company's 2013 Form 10-K.  The consolidated financial statements for the year ended September 30, 2014 will be audited by the Company's independent registered public accounting firm after the end of the fiscal year.
	The earnings for the six months ended March 31, 2014 should not be taken as a prediction of earnings for the entire fiscal year ending September 30, 2014.  Most of the business of the Utility and Energy Marketing segments is seasonal in nature and is influenced by weather conditions.  Due to the seasonal nature of the heating business in the Utility and Energy Marketing segments, earnings during the winter months normally represent a substantial part of the earnings that those segments are expected to achieve for the entire fiscal year.  The Company’s business segments are discussed more fully in Note 7 – Business Segment Information.
	Consolidated Statement of Cash Flows.  For purposes of the Consolidated Statement of Cash Flows, the Company considers all highly liquid debt instruments purchased with a maturity of generally three months or less to be cash equivalents.
	Hedging Collateral Deposits.  This is an account title for cash held in margin accounts funded by the Company to serve as collateral for hedging positions.  At March 31, 2014, the Company had no hedging collateral deposits outstanding. At September 30, 2013, the Company had hedging collateral deposits of $1.1 million related to its exchange-traded futures contracts.  In accordance with its accounting policy, the Company does not offset hedging collateral deposits paid or received against related derivative financial instruments liability or asset balances.
	Gas Stored Underground - Current.  In the Utility segment, gas stored underground – current is carried at lower of cost or market, on a LIFO method.  Gas stored underground – current normally declines during the first and second quarters of the year and is replenished during the third and fourth quarters.  In the Utility segment, the current cost of replacing gas withdrawn from storage is recorded in the Consolidated Statements of Income and a reserve for gas replacement is recorded in the Consolidated Balance Sheets under the caption “Other Accruals and Current Liabilities.”  Such reserve, which amounted to $73.9 million at March 31, 2014, is reduced to zero by September 30 of each year as the inventory is replenished.
	Property, Plant and Equipment.  In the Company’s Exploration and Production segment, oil and gas property acquisition, exploration and development costs are capitalized under the full cost method of accounting. Under this methodology, all costs associated with property acquisition, exploration and development activities are capitalized, including internal costs directly identified with acquisition, exploration and development activities. The internal costs that are capitalized do not include any costs related to production, general corporate overhead, or similar activities. The Company does not recognize any gain or loss on the sale or other disposition of oil and gas properties unless the gain or loss would significantly alter the relationship between capitalized costs and proved reserves of oil and gas attributable to a cost center.
	Capitalized costs include costs related to unproved properties, which are excluded from amortization until proved reserves are found or it is determined that the unproved properties are impaired.  Such costs amounted to $184.5 million and $106.1 million at March 31, 2014 and September 30, 2013, respectively.  All costs related to unproved properties are reviewed quarterly to determine if impairment has occurred. The amount of any impairment is transferred to the pool of capitalized costs being amortized.
	Capitalized costs are subject to the SEC full cost ceiling test. The ceiling test, which is performed each quarter, determines a limit, or ceiling, on the amount of property acquisition, exploration and development costs that can be capitalized. The ceiling under this test represents (a) the present value of estimated future net cash flows, excluding future cash outflows associated with settling asset retirement obligations that have been accrued on the balance sheet, using a discount factor of 10%, which is computed by applying prices of oil and gas (as adjusted for hedging) to estimated future production of proved oil and gas reserves as of the date of the latest balance sheet, less estimated future expenditures, plus (b) the cost of unevaluated properties not being depleted, less (c) income tax effects related to the differences between the book and tax basis of the properties. The natural gas and oil prices used to calculate the full cost ceiling are based on an unweighted arithmetic average of the first day of the month oil and gas prices for each month within the twelve-month period prior to the end of the reporting period. If capitalized costs, net of accumulated depreciation, depletion and amortization and related deferred income taxes, exceed the ceiling at the end of any quarter, a permanent impairment is required to be charged to earnings in that quarter.  At March 31, 2014, the ceiling exceeded the book value of the oil and gas properties by approximately $204.0 million.
	Accumulated Other Comprehensive Loss.  The components of Accumulated Other Comprehensive Loss and changes for the quarter and six months ended March 31, 2014, net of related tax effect, are as follows (amounts in parentheses indicate debits) (in thousands):
	Three Months Ended March 31, 2014
		Gains and Losses on Derivative Financial Instruments			Gains and Losses on Securities Available for Sale			Funded Status of the Pension and Other Post-Retirement Benefit Plans			Total
	Balance at January 1, 2014	$	26,345		$	7,910		$	(56,293	)	$	(22,038	)
	Other Comprehensive Gains and Losses Before Reclassifications	(38,878		)	391			—			(38,487		)
	Amounts Reclassified From Other Comprehensive Loss	15,470			—			—			15,470
	Balance at March 31, 2014	$	2,937		$	8,301		$	(56,293	)	$	(45,055	)
	Six Months Ended March 31, 2014
		Gains and Losses on Derivative Financial Instruments			Gains and Losses on Securities Available for Sale			Funded Status of the Pension and Other Post-Retirement Benefit Plans			Total
	Balance at October 1, 2013	$	30,722		$	6,337		$	(56,293	)	$	(19,234	)
	Other Comprehensive Gains and Losses Before Reclassifications	(37,370		)	1,964			—			(35,406		)
	Amounts Reclassified From Other Comprehensive Loss	9,585			—			—			9,585
	Balance at March 31, 2014	$	2,937		$	8,301		$	(56,293	)	$	(45,055	)
	Reclassifications Out of Accumulated Other Comprehensive Loss.  The details about the reclassification adjustments out of accumulated other comprehensive loss for the quarter and six months ended March 31, 2014 are as follows (amounts in parentheses indicate debits to the income statement) (in thousands):
	Three Months Ended March 31, 2014
	Details About Accumulated Other Comprehensive Loss Components	Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Loss			Affected Line Item in the Statement Where Net Income is Presented
	Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges:
	Commodity Contracts		($22,611	)	Operating Revenues
	Commodity Contracts	(4,029		)	Purchased Gas
		(26,640		)	Total Before Income Tax
		11,170			Income Tax Expense
			($15,470	)	Net of Tax
	Six Months Ended March 31, 2014
	Details About Accumulated Other Comprehensive Loss Components	Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Loss			Affected Line Item in the Statement Where Net Income is Presented
	Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges:
	Commodity Contracts		($12,825	)	Operating Revenues
	Commodity Contracts	(3,632		)	Purchased Gas
		(16,457		)	Total Before Income Tax
		6,872			Income Tax Expense
			($9,585	)	Net of Tax
	Other Current Assets.  The components of the Company’s Other Current Assets are as follows (in thousands):
		At March 31, 2014				At September 30, 2013
	Prepayments	$	4,221			$	10,605
	Prepaid Property and Other Taxes	21,950				13,079
	Federal Income Taxes Receivable	—				1,122
	State Income Taxes Receivable	—				3,275
	Fair Values of Firm Commitments	—				1,829
	Regulatory Assets	28,732				26,995
		$	54,903			$	56,905
	Other Accruals and Current Liabilities.  The components of the Company’s Other Accruals and Current Liabilities are as follows (in thousands):
		At March 31, 2014				At September 30, 2013
	Accrued Capital Expenditures	$	90,831			$	41,100
	Regulatory Liabilities	11,085				20,013
	Reserve for Gas Replacement	73,883				—
	Federal Income Taxes Payable	30,802				—
	State Income Taxes Payable	4,063				—
	Other	25,236				22,833
		$	235,900			$	83,946
	Earnings Per Common Share.  Basic earnings per common share is computed by dividing net income available for common stock by the weighted average number of common shares outstanding for the period. Diluted earnings per common share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock.  For purposes of determining earnings per common share, the potentially dilutive securities the Company has outstanding are stock options, SARs, restricted stock units and performance shares.  The diluted weighted average shares outstanding shown on the Consolidated Statements of Income reflects the potential dilution as a result of these securities as determined using the Treasury Stock Method.  Stock options, SARs, restricted stock units and performance shares that are antidilutive are excluded from the calculation of diluted earnings per common share.  There were no securities excluded as being antidilutive for the quarter ended March 31, 2014. There were 265 securities excluded as being antidilutive for the six months ended March 31, 2014.  There were 208,819 and 362,681 securities excluded as being antidilutive for the quarter and six months ended March 31, 2013, respectively.
	Stock-Based Compensation.  The Company granted 116,090 performance shares during the six months ended March 31, 2014. The weighted average fair value of such performance shares was $67.16 per share for the six months ended March 31, 2014. Performance shares are an award constituting units denominated in common stock of the Company, the number of which may be adjusted over a performance cycle based upon the extent to which performance goals have been satisfied.  Earned performance shares may be distributed in the form of shares of common stock of the Company, an equivalent value in cash or a combination of cash and shares of common stock of the Company, as determined by the Company. The performance shares do not entitle the participant to receive dividends during the vesting period.
	Half of the performance shares granted during the six months ended March 31, 2014 must meet a performance goal related to relative return on capital over the performance cycle of October 1, 2013 to September 30, 2016.  The performance goal over the performance cycle is the Company’s total return on capital relative to the total return on capital of other companies in a group selected by the Compensation Committee (“Report Group”).  Total return on capital for a given company means the average of the Report Group companies’ returns on capital for each twelve month period corresponding to each of the Company’s fiscal years during the performance cycle, based on data reported for the Report Group companies in the Bloomberg database.  The number of these performance shares that will vest and be paid will depend upon the Company’s performance relative to the Report Group and not upon the absolute level of return achieved by the Company.  The fair value of these performance shares is calculated by multiplying the expected number of shares that will be issued by the average market price of Company common stock on the date of grant reduced by the present value of forgone dividends over the vesting term of the award.  The fair value is recorded as compensation expense over the vesting term of the award.  The other half of the performance shares granted during the six months ended March 31, 2014 must meet a performance goal related to total shareholder return over the performance cycle of October 1, 2013 to September 30, 2016.  The performance goal over the performance cycle is the Company’s three-year total shareholder return relative to the three-year total shareholder return of the other companies in the Report Group.  Three-year shareholder return for a given company will be based on the data reported for that company (with the starting and ending stock prices over the performance cycle calculated as the average closing stock price for the prior calendar month and with dividends reinvested in that company’s securities at each ex-dividend date) in the Bloomberg database.  The number of these performance shares that will vest and be paid will depend upon the Company’s performance relative to the Report Group and not upon the absolute level of return achieved by the Company.  The fair value price at the date of grant for these performance shares is determined using a Monte Carlo simulation technique, which includes a reduction in value for the present value of forgone dividends over the vesting term of the award.  This price is multiplied by the number of performance shares awarded, the result of which is recorded as compensation expense over the vesting term of the award.
The Company granted 80,951 non-performance based restricted stock units during the six months ended March 31, 2014.  The weighted average fair value of such non-performance based restricted stock units was $65.23 per share for the six months ended March 31, 2014. Restricted stock units represent the right to receive shares of common stock of the Company (or the equivalent value in cash or a combination of cash and shares of common stock of the Company, as determined by the Company) at the end of a specified time period. These non-performance based restricted stock units do not entitle the participant to receive dividends during the vesting period. The accounting for non-performance based restricted stock units is the same as the accounting for restricted share awards, except that the fair value at the date of grant of the restricted stock units must be reduced by the present value of forgone dividends over the vesting term of the award.
No stock options, SARs or restricted share awards were granted by the Company during the six months ended March 31, 2014.

Fair_Value_Measurements

Fair Value Measurements	6 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements
	The FASB authoritative guidance regarding fair value measurements establishes a fair-value hierarchy and prioritizes the inputs used in valuation techniques that measure fair value. Those inputs are prioritized into three levels. Level 1 inputs are unadjusted quoted prices in active markets for assets or liabilities that the Company can access at the measurement date. Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly at the measurement date. Level 3 inputs are unobservable inputs for the asset or liability at the measurement date. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels.
	The following table sets forth, by level within the fair value hierarchy, the Company's financial assets and liabilities (as applicable) that were accounted for at fair value on a recurring basis as of March 31, 2014 and September 30, 2013.  Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.  The fair value presentation for over the counter swaps has been changed to combine gas and oil swaps at both March 31, 2014 and September 30, 2013.  In the September 30, 2013 Form 10-K, gas swaps were reported separately from oil swaps.  This change in presentation was made because a significant number of the counterparties enter into both gas and oil swap agreements with the Company.
	Recurring Fair Value Measures	At fair value as of March 31, 2014
	(Thousands of Dollars)	Level 1				Level 2				Level 3				Netting Adjustments(1)				Total(1)
	Assets:
	Cash Equivalents – Money Market Mutual Funds	$	129,892			$	—			$	—			$	—			$	129,892
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	3,297				—				—				(847		)		2,450
	Over the Counter Swaps – Gas and Oil	—				48,284				273				(25,230		)		23,327
	Other Investments:
	Balanced Equity Mutual Fund	34,407				—				—				—				34,407
	Common Stock – Financial Services Industry	7,631				—				—				—				7,631
	Other Common Stock	383				—				—				—				383
	Hedging Collateral Deposits	—				—				—				—				—
	Total	$	175,610			$	48,284			$	273			$	(26,077	)		$	198,090
	Liabilities:
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	$	847			$	—			$	—			$	(847	)		$	—
	Over the Counter Swaps – Gas and Oil	—				45,822				1,644				(25,230		)		22,236
	Total	$	847			$	45,822			$	1,644			$	(26,077	)		$	22,236
	Total Net Assets/(Liabilities)	$	174,763			$	2,462			$	(1,371	)		$	—			$	175,854
	Recurring Fair Value Measures	At fair value as of September 30, 2013
	(Thousands of Dollars)	Level 1				Level 2				Level 3				Netting Adjustments(1)				Total(1)
	Assets:
	Cash Equivalents – Money Market Mutual Funds	$	51,332			$	—			$	—			$	—			$	51,332
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	2,552				—				—				(1,641		)		911
	Over the Counter Swaps – Gas and Oil	—				57,070				—				(9,003		)		48,067
	Other Investments:
	Balanced Equity Mutual Fund	31,813				—				—				—				31,813
	Common Stock – Financial Services Industry	6,544				—				—				—				6,544
	Other Common Stock	330				—				—				—				330
	Hedging Collateral Deposits	1,094				—				—				—				1,094
	Total	$	93,665			$	57,070			$	—			$	(10,644	)		$	140,091
	Liabilities:
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	$	1,641			$	—			$	—			$	(1,641	)		$	—
	Over the Counter Swaps – Gas and Oil	—				4,452				5,190				(9,003		)		639
	Total	$	1,641			$	4,452			$	5,190			$	(10,644	)		$	639
	Total Net Assets/(Liabilities)	$	92,024			$	52,618			$	(5,190	)		$	—			$	139,452
	(1)	Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.
	Derivative Financial Instruments
	At March 31, 2014 and September 30, 2013, the derivative financial instruments reported in Level 1 consist of natural gas NYMEX and ICE futures contracts used in the Company’s Energy Marketing segment. Hedging collateral deposits of $1.1 million at September 30, 2013, which are associated with these futures contracts, have been reported in Level 1 as well. The derivative financial instruments reported in Level 2 at March 31, 2014 and September 30, 2013 consist of natural gas price swap agreements used in the Company’s Exploration and Production and Energy Marketing segments and the majority of the crude oil price swap agreements used in the Company’s Exploration and Production segment. The fair value of the Level 2 price swap agreements is based on an internal, discounted cash flow model that uses observable inputs (i.e. LIBOR based discount rates and basis differential information, if applicable, at active natural gas and crude oil trading markets). The derivative financial instruments reported in Level 3 consist of a portion of the crude oil price swap agreements used in the Company’s Exploration and Production segment at March 31, 2014 and September 30, 2013.  The fair value of the Level 3 crude oil price swap agreements is based on an internal, discounted cash flow model that uses both observable (i.e. LIBOR based discount rates) and unobservable inputs (i.e. basis differential information of crude oil trading markets with low trading volume).
	The significant unobservable input used in the fair value measurement of a portion of the Company’s over-the-counter crude oil swaps is the basis differential between Midway Sunset oil and NYMEX contracts.  Significant changes in the assumed basis differential could result in a significant change in value of the derivative financial instruments.  At March 31, 2014, it was assumed that Midway Sunset oil was 100.3% of NYMEX.  This is based on a historical twelve month average of Midway Sunset oil sales verses NYMEX settlements.  During this twelve-month period, the price of Midway Sunset oil ranged from 96.2% to 108.1% of NYMEX.  If the basis differential between Midway Sunset oil and NYMEX contracts used in the fair value measurement calculation at March 31, 2014 had been 10 percentage points higher, the fair value of the Level 3 crude oil price swap agreements liability would have been approximately $5.8 million higher.  If the basis differential between Midway Sunset oil and NYMEX contracts used in the fair value measurement at March 31, 2014 had been 10 percentage points lower, the fair value measurement of the Level 3 crude oil price swap agreements liability would have changed from a net liability of $1.4 million to a net asset of $4.4 million.  These calculated amounts are based solely on basis differential changes and do not take into account any other changes to the fair value measurement calculation.
	The accounting rules for fair value measurements and disclosures require consideration of the impact of nonperformance risk (including credit risk) from a market participant perspective in the measurement of the fair value of assets and liabilities.  At March 31, 2014, the Company determined that nonperformance risk would have no material impact on its financial position or results of operation.  To assess nonperformance risk, the Company considered information such as any applicable collateral posted, master netting arrangements, and applied a market-based method by using the counterparty (for an asset) or the Company’s (for a liability) credit default swaps rates.
	The tables listed below provide reconciliations of the beginning and ending net balances for assets and liabilities measured at fair value and classified as Level 3 for the quarters and six months ended March 31, 2014 and 2013, respectively. For the quarters and six months ended March 31, 2014 and March 31, 2013, no transfers in or out of Level 1 or Level 2 occurred.  There were no purchases or sales of derivative financial instruments during the periods presented in the tables below.  All settlements of the derivative financial instruments are reflected in the Gains/Losses Realized and Included in Earnings column of the tables below (amounts in parentheses indicate credits in the derivative asset/liability accounts).
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Jan-14			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2014
	Derivative Financial Instruments(2)	$	(1,842	)	$	763		(1)	$	(292	)	$	—		$	(1,371	)
	(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2014.
	(2)	Derivative Financial Instruments are shown on a net basis.
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Oct-13			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2014
	Derivative Financial Instruments(2)	$	(5,190	)	$	1,043		(1)	$	2,776		$	—		$	(1,371	)
	(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the six months ended March 31, 2014.
	(2)	Derivative Financial Instruments are shown on a net basis.
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Jan-13			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2013
	Derivative Financial Instruments(2)	$	(14,089	)	$	4,539		(1)	$	(7,056	)	$	—		$	(16,606	)
(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2013.
(2)	Derivative Financial Instruments are shown on a net basis.
Fair Value Measurements Using Unobservable Inputs (Level 3)
(Thousands of Dollars)				Total Gains/Losses
	1-Oct-12			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2013
Derivative Financial Instruments(2)	$	(19,664	)	$	6,801		(1)	$	(3,743	)	$	—		$	(16,606	)
(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the six months ended March 31, 2013.
(2)	Derivative Financial Instruments are shown on a net basis.

Financial_Instruments

Financial Instruments	6 Months Ended
	Mar. 31, 2014
Financial Instruments, Owned, at Fair Value [Abstract]	'
Financial Instruments	'
	Financial Instruments
	Long-Term Debt.  The fair market value of the Company’s debt, as presented in the table below, was determined using a discounted cash flow model, which incorporates the Company’s credit ratings and current market conditions in determining the yield, and subsequently, the fair market value of the debt.  Based on these criteria, the fair market value of long-term debt, including current portion, was as follows (in thousands):
		March 31, 2014								September 30, 2013
		Carrying Amount				Fair Value				Carrying Amount				Fair Value
	Long-Term Debt	$	1,649,000			$	1,787,823			$	1,649,000			$	1,767,519
	The fair value amounts are not intended to reflect principal amounts that the Company will ultimately be required to pay. Carrying amounts for other financial instruments recorded on the Company’s Consolidated Balance Sheets approximate fair value. The fair value of long-term debt was calculated using observable inputs (U.S. Treasuries/LIBOR for the risk free component and company specific credit spread information – generally obtained from recent trade activity in the debt).  As such, the Company considers the debt to be Level 2.
	Any temporary cash investments, notes payable to banks and commercial paper are stated at cost. Temporary cash investments are considered Level 1, while notes payable to banks and commercial paper are considered to be Level 2.  Given the short-term nature of the notes payable to banks and commercial paper, the Company believes cost is a reasonable approximation of fair value.
	Other Investments.  Investments in life insurance are stated at their cash surrender values or net present value as discussed below. Investments in an equity mutual fund and the stock of an insurance company (marketable equity securities), as discussed below, are stated at fair value based on quoted market prices.
	Other investments include cash surrender values of insurance contracts (net present value in the case of split-dollar collateral assignment arrangements) and marketable equity securities. The values of the insurance contracts amounted to $43.4 million at March 31, 2014 and $57.6 million at September 30, 2013. The fair value of the equity mutual fund was $34.4 million at March 31, 2014 and $31.8 million at September 30, 2013. The gross unrealized gain on this equity mutual fund was $7.7 million at March 31, 2014 and $5.7 million at September 30, 2013.  The fair value of the stock of an insurance company was $7.6 million at March 31, 2014 and $6.5 million at September 30, 2013. The gross unrealized gain on this stock was $5.2 million at March 31, 2014 and $4.1 million at September 30, 2013. The insurance contracts and marketable equity securities are primarily informal funding mechanisms for various benefit obligations the Company has to certain employees.
	Derivative Financial Instruments.  The Company uses derivative instruments to manage commodity price risk in the Exploration and Production and Energy Marketing segments. During 2012, the Pipeline and Storage segment discontinued its use of derivative instruments as a means of managing commodity price risk.  The Company enters into futures contracts and over-the-counter swap agreements for natural gas and crude oil to manage the price risk associated with forecasted sales of gas and oil. The Company also enters into futures contracts and swaps to manage the risk associated with forecasted gas purchases, forecasted gas sales, storage of gas, withdrawal of gas from storage to meet customer demand and the potential decline in the value of gas held in storage. The duration of the Company’s hedges does not typically exceed 5 years.
	The Company has presented its net derivative assets and liabilities as “Fair Value of Derivative Financial Instruments” on its Consolidated Balance Sheets at March 31, 2014 and September 30, 2013.  All of the derivative financial instruments reported on those line items relate to commodity contracts.
	Cash Flow Hedges
	For derivative instruments that are designated and qualify as a cash flow hedge, the effective portion of the gain or loss on the derivative is reported as a component of other comprehensive income (loss) and reclassified into earnings in the period or periods during which the hedged transaction affects earnings.  Gains and losses on the derivative representing either hedge ineffectiveness or hedge components excluded from the assessment of effectiveness are recognized in current earnings.
	As of March 31, 2014, the Company’s Exploration and Production segment had the following commodity derivative contracts (swaps) outstanding to hedge forecasted sales (where the Company uses short positions (i.e. positions that pay-off in the event of commodity price decline) to mitigate the risk of decreasing revenues and earnings):
	Commodity	Units
	Natural Gas	239		Bcf (all short positions)
	Crude Oil	4,269,000		Bbls (all short positions)
	At March 31, 2014, the Company de-designated a portion of its crude oil swaps as cash flow hedges and simultaneously re-designated them as cash flow hedges using a revised effectiveness testing model. Amounts in accumulated other comprehensive loss at March 31, 2014 associated with the de-designated crude oil swaps will be amortized into the income statement as the anticipated hedged production occurs. Since the de-designated crude oil swaps were re-designated as cash flow hedges at March 31, 2014, future gains or losses on such derivatives, to the extent they are effective, will be reported as a component of other comprehensive income (loss) and reclassified into earnings in the period or periods during which the hedged transaction affects earnings. The total mark-to-market adjustment recorded in earnings related to all of the Company's crude oil swaps, including economic hedges, was a $1.8 million loss for the quarter ended March 31, 2014. The mark-to-market impact for the six months ended March 31, 2014 was insignificant.
	As of March 31, 2014, the Company’s Energy Marketing segment had the following commodity derivative contracts (futures contracts and swaps) outstanding to hedge forecasted sales (where the Company uses short positions to mitigate the risk associated with natural gas price decreases and its impact on decreasing revenues and earnings) and, when applicable, purchases (where the Company uses long positions (i.e. positions that pay-off in the event of commodity price increases) to mitigate the risk of increasing natural gas prices, which would lead to increased purchased gas expense and decreased earnings):
	Commodity	Units
	Natural Gas	3.5		Bcf short positions (mostly forecasted storage withdrawals)
		3.4		Bcf long positions (mostly forecasted storage injections)
		6.9		Total Bcf
	As of March 31, 2014, the Company’s Exploration and Production segment had $4.8 million ($2.8 million after tax) of net hedging gains included in the accumulated other comprehensive income (loss) balance. It is expected that $31.5 million ($18.7 million after tax) of unrealized losses will be reclassified into the Consolidated Statement of Income within the next 12 months as the expected sales of the underlying commodities occur. It is expected that $36.3 million ($21.5 million after tax) of unrealized gains will be reclassified into the Consolidated Statement of Income after 12 months as the expected sales of the underlying commodities occur.
	As of March 31, 2014, the Company’s Energy Marketing segment had $0.2 million ($0.1 million after tax) of net hedging gains included in the accumulated other comprehensive income (loss) balance. It is expected that $0.1 million (less than $0.1 million after tax) of unrealized gains will be reclassified into the Consolidated Statement of Income (Loss) within the next 12 months as the expected sales of the underlying commodity occurs. It is expected that $0.1 million (less than $0.1 million after tax) of unrealized gains will be reclassified into the Consolidated Statement of Income after 12 months as the expected sales of the underlying commodities occur.
	Refer to Note 1, under Accumulated Other Comprehensive Income (Loss), for the after-tax gain (loss) pertaining to derivative financial instruments for the Exploration and Production and Energy Marketing segments.
	The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the
	Three Months Ended March 31, 2014 and 2013 (Thousands of Dollars)
	Derivatives in Cash Flow Hedging Relationships	Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion) for the Three Months Ended March 31,						Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion) for the Three Months Ended March 31,						Location of Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing) for the Three Months Ended March 31,
		2014			2013				2014			2013				2014			2013
	Commodity Contracts - Exploration & Production segment	$	(64,237	)	$	(47,364	)	Operating Revenue	$	(22,611	)	$	11,285		Operating Revenue	$	(660	)	$	(456	)
	Commodity Contracts - Energy Marketing segment	$	(3,224	)	$	14		Purchased Gas	$	(4,029	)	$	(782	)	Not Applicable	$	—		$	—
	Commodity Contracts - Pipeline & Storage segment (1)	$	—		$	—		Operating Revenue	$	—		$	—		Not Applicable	$	—		$	—
	Total	$	(67,461	)	$	(47,350	)		$	(26,640	)	$	10,503			$	(660	)	$	(456	)
	The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the
	Six Months Ended March 31, 2014 and 2013 (Thousands of Dollars)
	Derivatives in Cash Flow Hedging Relationships	Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion) for the Six Months Ended March 31,						Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion) for the Six Months Ended March 31,						Location of Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing) for the Six Months Ended March 31,
		2014			2013				2014			2013				2014			2013
	Commodity Contracts - Exploration & Production segment	$	(59,117	)	$	(13,750	)	Operating Revenue	$	(12,825	)	$	23,590		Operating Revenue	$	774		$	(456	)
	Commodity Contracts - Energy Marketing segment	$	(5,565	)	$	1,749		Purchased Gas	$	(3,632	)	$	(830	)	Not Applicable	$	—		$	—
	Commodity Contracts - Pipeline & Storage segment (1)	$	—		$	—		Operating Revenue	$	—		$	(672	)	Not Applicable	$	—		$	—
	Total	$	(64,682	)	$	(12,001	)		$	(16,457	)	$	22,088			$	774		$	(456	)
	(1)	There were no open hedging positions at March 31, 2014 or 2013.
	Fair Value Hedges
	The Company’s Energy Marketing segment utilizes fair value hedges to mitigate risk associated with fixed price sales commitments, fixed price purchase commitments, and the decline in the value of certain natural gas held in storage. With respect to fixed price sales commitments, the Company enters into long positions to mitigate the risk of price increases for natural gas supplies that could occur after the Company enters into fixed price sales agreements with its customers. With respect to fixed price purchase commitments, the Company enters into short positions to mitigate the risk of price decreases that could occur after the Company locks into fixed price purchase deals with its suppliers. With respect to storage hedges, the Company enters into short positions to mitigate the risk of price decreases that could result in a lower of cost or market writedown of the value of natural gas in storage that is recorded in the Company’s financial statements. As of March 31, 2014, the Company’s Energy Marketing segment had fair value hedges covering approximately 7.5 Bcf (7.0 Bcf of fixed price sales commitments (mostly long positions) and 0.5 Bcf of fixed price purchase commitments (mostly short positions)). For derivative instruments that are designated and qualify as a fair value hedge, the gain or loss on the derivative as well as the offsetting gain or loss on the hedged item attributable to the hedged risk completely offset each other in current earnings, as shown below.
	Derivatives in Fair Value Hedging Relationships – Energy Marketing segment	Location of Gain or (Loss) on Derivative and Hedged Item Recognized in the Consolidated Statement of Income	Amount of Gain or (Loss) on Derivative Recognized in the Consolidated Statement of Income for the Six Months Ended March 31, 2014 (In Thousands)			Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income for the Six Months Ended March 31, 2014 (In Thousands)
	Commodity Contracts – Hedge of fixed price sales commitments of natural gas	Operating Revenues	$	3,779		$	(3,779	)
	Commodity Contracts – Hedge of fixed price purchase commitments of natural gas	Purchased Gas	$	(440	)	$	440
	Commodity Contracts – Hedge of natural gas held in storage	Purchased Gas	$	(38	)	$	38
			$	3,301		$	(3,301	)
	Credit Risk
	The Company may be exposed to credit risk on any of the derivative financial instruments that are in a gain position. Credit risk relates to the risk of loss that the Company would incur as a result of nonperformance by counterparties pursuant to the terms of their contractual obligations. To mitigate such credit risk, management performs a credit check, and then on a quarterly basis monitors counterparty credit exposure. The majority of the Company’s counterparties are financial institutions and energy traders. The Company has over-the-counter swap positions with fifteen counterparties of which four are in a net gain position.   On average, the Company had $5.8 million of credit exposure per counterparty in a gain position at March 31, 2014. The maximum credit exposure per counterparty in a gain position at March 31, 2014 was $9.6 million. As of March 31, 2014, no collateral was received from the counterparties by the Company.  The Company’s gain position on such derivative financial instruments had not exceeded the established thresholds at which the counterparties would be required to post collateral, nor had the counterparties’ credit ratings declined to levels at which the counterparties were required to post collateral.
	As of March 31, 2014, twelve of the fifteen counterparties to the Company’s outstanding derivative instrument contracts (specifically the over-the-counter swaps) had a common credit-risk related contingency feature. In the event the Company’s credit rating increases or falls below a certain threshold (applicable debt ratings), the available credit extended to the Company would either increase or decrease. A decline in the Company’s credit rating, in and of itself, would not cause the Company to be required to increase the level of its hedging collateral deposits (in the form of cash deposits, letters of credit or treasury debt instruments). If the Company’s outstanding derivative instrument contracts were in a liability position (or if the current liability were larger) and/or the Company’s credit rating declined, then additional hedging collateral deposits may be required.  At March 31, 2014, the fair market value of the derivative financial instrument assets with a credit-risk related contingency feature was $22.3 million according to the Company’s internal model (discussed in Note 2 — Fair Value Measurements).  At March 31, 2014, the fair market value of the derivative financial instrument liabilities with a credit-risk related contingency feature was $19.1 million according to the Company’s internal model  (discussed in Note 2 — Fair Value Measurements).  For its over-the-counter swap agreements, no hedging collateral deposits were required to be posted by the Company at March 31, 2014.
	For its exchange traded futures contracts, which are in an asset position, no hedging collateral deposits were required to be posted by the Company as of March 31, 2014.   As these are exchange traded futures contracts, there are no specific credit-risk related contingency features. The Company posts hedging collateral based on open positions and margin requirements it has with its counterparties.
	The Company’s requirement to post hedging collateral deposits is based on the fair value determined by the Company’s counterparties, which may differ from the Company’s assessment of fair value. Hedging collateral deposits may also include closed derivative positions in which the broker has not cleared the cash from the account to offset the derivative liability. The Company records liabilities related to closed derivative positions in Other Accruals and Current Liabilities on the Consolidated Balance Sheet. These liabilities are relieved when the broker clears the cash from the hedging collateral deposit account. This is discussed in Note 1 under Hedging Collateral Deposits.

Income_Taxes

Income Taxes	6 Months Ended
	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	The components of federal and state income taxes included in the Consolidated Statements of Income are as follows (in thousands):
		Six Months Ended
		March 31,
		2014			2013
	Current Income Taxes
	Federal	$	39,974		$	(6,318	)
	State	9,607			2,496
	Deferred Income Taxes
	Federal	50,110			82,788
	State	21,829			19,769
		121,520			98,735
	Deferred Investment Tax Credit	(218		)	(213		)
	Total Income Taxes	$	121,302		$	98,522
	Presented as Follows:
	Other Income	(218		)	(213		)
	Income Tax Expense	121,520			98,735
	Total Income Taxes	$	121,302		$	98,522
	Total income taxes as reported differ from the amounts that were computed by applying the federal income tax rate to income before income taxes.  The following is a reconciliation of this difference (in thousands):
		Six Months Ended
		March 31,
		2014			2013
	U.S. Income Before Income Taxes	$	298,765		$	252,186
	Income Tax Expense, Computed at U.S. Federal Statutory Rate of 35%	$	104,568		$	88,265
	Increase (Reduction) in Taxes Resulting from:
	State Income Taxes	20,433			14,473
	Miscellaneous	(3,699		)	(4,216		)
	Total Income Taxes	$	121,302		$	98,522
	Significant components of the Company’s deferred tax liabilities and assets were as follows (in thousands):
		At March 31, 2014			At September 30, 2013
	Deferred Tax Liabilities:
	Property, Plant and Equipment	$	1,551,701		$	1,504,187
	Pension and Other Post-Retirement Benefit Costs	121,780			124,021
	Other	55,562			75,419
	Total Deferred Tax Liabilities	1,729,043			1,703,627
	Deferred Tax Assets:
	Pension and Other Post-Retirement Benefit Costs	(132,752		)	(130,256		)
	Tax Loss Carryforwards	(184,123		)	(215,262		)
	Other	(99,087		)	(90,461		)
	Total Deferred Tax Assets	(415,962		)	(435,979		)
	Total Net Deferred Income Taxes	$	1,313,081		$	1,267,648
	Presented as Follows:
	Net Deferred Tax Liability/(Asset) – Current	(39,650		)	(79,359		)
	Net Deferred Tax Liability – Non-Current	1,352,731			1,347,007
	Total Net Deferred Income Taxes	$	1,313,081		$	1,267,648
	As a result of certain realization requirements of the authoritative guidance on stock-based compensation, the table of deferred tax liabilities and assets shown above does not include certain deferred tax assets that arose directly from excess tax deductions related to stock-based compensation. Tax benefits of $3.1 million and $0.7 million relating to the excess stock-based compensation deductions were recorded in Paid in Capital during the six months ended March 31, 2014 and the year ended September 30, 2013, respectively.  Cumulative tax benefits of $36.4 million remain at both March 31, 2014 and September 30, 2013 and will be recorded in Paid in Capital in future years when such tax benefits are realized.
	Regulatory liabilities representing the reduction of previously recorded deferred income taxes associated with rate-regulated activities that are expected to be refundable to customers amounted to $90.8 million and $85.7 million at March 31, 2014 and September 30, 2013, respectively.  Also, regulatory assets representing future amounts collectible from customers, corresponding to additional deferred income taxes not previously recorded because of prior ratemaking practices, amounted to $161.3 million and $163.4 million at March 31, 2014 and September 30, 2013, respectively.
	During the quarter ended March 31, 2014, there was no change in the balance of unrecognized tax benefits.  Approximately $2.0 million of the remaining balance of unrecognized tax benefits would favorably impact the effective tax rate, if recognized.  It is reasonably possible that a reduction of $2.0 million of the balance of uncertain tax positions may occur as a result of potential settlements with taxing authorities within the next twelve months.
	The Internal Revenue Service (IRS) is currently conducting examinations of the Company for fiscal 2012, fiscal 2013 and fiscal 2014 in accordance with the Compliance Assurance Process (CAP).  The CAP audit employs a real time review of the Company’s books and tax records by the IRS that is intended to permit issue resolution prior to the filing of the tax return.  While the federal statute of limitations remains open for fiscal 2009 and later years, IRS examinations for fiscal 2008 and prior years have been completed and the Company believes such years are effectively settled.  During fiscal 2009, consent was received from the IRS National Office approving the Company’s application to change its tax method of accounting for certain capitalized costs relating to its utility property.  During the quarter ended March 31, 2013, local IRS examiners issued no-change reports for fiscal 2009, fiscal 2010 and fiscal 2011, but have reserved the right to re-examine these years, pending the anticipated issuance of IRS guidance addressing the issue for natural gas utilities.
	The Company is also subject to various routine state income tax examinations.  The Company’s principal subsidiaries operate mainly in four states which have statutes of limitations that generally expire between three to four years from the date of filing of the income tax return.
	On March 31, 2014, the New York State fiscal year 2014-2015 Executive Budget legislation was signed into law. This legislation included numerous tax provisions, including a reduction of the corporate tax rate from 7.1% to 6.5%, effective for tax years beginning after January 1, 2016. This provision resulted in a tax benefit of approximately $2.8 million, which is reflected in the accompanying financial statements.

Capitalization

Capitalization	6 Months Ended
	Mar. 31, 2014
Capitalization, Long-term Debt and Equity [Abstract]	'
Capitalization	'
	Capitalization
	Common Stock.  During the six months ended March 31, 2014, the Company issued 301,793 original issue shares of common stock as a result of stock option and SARs exercises and 8,732 original issue shares of common stock for restricted stock units that vested.  In addition, the Company issued 47,943 original issue shares of common stock for the Direct Stock Purchase and Dividend Reinvestment Plan and 32,053 original issue shares of common stock for the Company’s 401(k) plans.  The Company also issued 7,712 original issue shares of common stock to the non-employee directors of the Company who receive compensation under the Company’s 2009 Non-Employee Director Equity Compensation Plan, as partial consideration for the directors’ services during the six months ended March 31, 2014.  Holders of stock options, SARs, restricted share awards or restricted stock units will often tender shares of common stock to the Company for payment of option exercise prices and/or applicable withholding taxes.  During the six months ended March 31, 2014, 79,606 shares of common stock were tendered to the Company for such purposes.  The Company considers all shares tendered as cancelled shares restored to the status of authorized but unissued shares, in accordance with New Jersey law.
	Current Portion of Long-Term Debt.    None of the Company’s long-term debt at March 31, 2014 will mature within the following twelve-month period.

Commitments_And_Contingencies

Commitments And Contingencies	6 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments And Contingencies	'
	Commitments and Contingencies
	Environmental Matters.  The Company is subject to various federal, state and local laws and regulations relating to the protection of the environment.  The Company has established procedures for the ongoing evaluation of its operations to identify potential environmental exposures and to comply with regulatory policies and procedures.  It is the Company’s policy to accrue estimated environmental clean-up costs (investigation and remediation) when such amounts can reasonably be estimated and it is probable that the Company will be required to incur such costs.
	At March 31, 2014, the Company has estimated its remaining clean-up costs related to former manufactured gas plant sites and third party waste disposal sites will be approximately $14.1 million.  The Company expects to recover such environmental clean-up costs through rate recovery over a period of approximately 13 years.
	The Company's estimated liability for clean-up costs discussed above includes a $13.0 million estimated liability to remediate a former manufactured gas plant site located in New York.  In February 2009, the Company received approval from the NYDEC of a Remedial Design Work Plan (RDWP) for this site. In October 2010, the Company submitted a RDWP addendum to conduct additional Preliminary Design Investigation field activities necessary to design a successful remediation. As a result of this work, the Company submitted to the NYDEC a proposal to amend the NYDEC’s Record of Decision remedy for the site.  In April 2013, the NYDEC approved the Company’s proposed amendment.  Final remedial design work for the site has begun.
	The Company is currently not aware of any material additional exposure to environmental liabilities.  However, changes in environmental laws and regulations, new information or other factors could have an adverse financial impact on the Company.
	Other.  The Company is involved in other litigation and regulatory matters arising in the normal course of business.  These other matters may include, for example, negligence claims and tax, regulatory or other governmental audits, inspections, investigations and other proceedings.  These matters may involve state and federal taxes, safety, compliance with regulations, rate base, cost of service and purchased gas cost issues, among other things.  While these other matters arising in the normal course of business could have a material effect on earnings and cash flows in the period in which they are resolved, an estimate of the possible loss or range of loss, if any, cannot be made at this time.

Business_Segment_Information

Business Segment Information	6 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Business Segment Information	'
	Business Segment Information
	The Company reports financial results for five segments: Utility, Pipeline and Storage, Exploration and Production, Energy Marketing and Gathering.  The division of the Company’s operations into reportable segments is based upon a combination of factors including differences in products and services, regulatory environment and geographic factors.
	The data presented in the tables below reflect financial information for the segments and reconciliations to consolidated amounts.  As stated in the 2013 Form 10-K, the Company evaluates segment performance based on income before discontinued operations, extraordinary items and cumulative effects of changes in accounting (when applicable).  When these items are not applicable, the Company evaluates performance based on net income.  There have not been any changes in the basis of segmentation nor in the basis of measuring segment profit or loss from those used in the Company’s 2013 Form 10-K.  As for segment assets at March 31, 2014, there have been changes from the segment assets disclosed in the 2013 Form 10-K.  A listing of segment assets at March 31, 2014 and September 30, 2013 is shown in the tables below.  Energy Marketing segment revenue from external customers and net income for the quarter ended March 31, 2014 reflect the impact of $8.2 million and $0.4 million, respectively, of unbilled revenue and related decline in margin (net of tax).  For the six months ended March 31, 2014, Energy Marketing segment revenue from external customers and net income reflect the impact of $33.7 million and $0.9 million, respectively, of unbilled revenue and related incremental margin (net of tax).  In prior periods, Energy Marketing segment revenues and related purchased gas costs were recorded when billed, resulting in a one month lag.  The impact of not recording unbilled revenue and related costs was immaterial in all prior periods.
	Quarter Ended March 31, 2014 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$377,647	$53,571	$199,561	$124,439	$195	$755,413	$597	$232	$756,242
	Intersegment Revenues	$8,204	$22,235	$—	$5	$15,452	$45,896	$—	($45,896)	$—
	Segment Profit: Net Income	$35,545	$21,372	$24,390	$3,765	$7,324	$92,396	$278	$2,537	$95,211
	Six Months Ended March 31, 2014 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$608,100	$104,784	$392,607	$197,598	$429	$1,303,518	$2,298	$498	$1,306,314
	Intersegment Revenues	$12,911	$42,974	$—	$260	$29,802	$85,947	$—	($85,947)	$—
	Segment Profit: Net Income	$59,760	$40,510	$55,487	$5,369	$13,471	$174,597	$954	$1,912	$177,463
	(Thousands)	Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Segment Assets:
	At March 31, 2014	$2,019,438	$1,283,654	$2,821,355	$110,285	$247,286	$6,482,018	$95,849	($10,672)	$6,567,195
	At September 30, 2013	$1,870,587	$1,246,027	$2,746,233	$67,267	$203,323	$6,133,437	$95,793	($10,883)	$6,218,347
	Quarter Ended March 31, 2013 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$303,389	$46,383	$168,080	$78,989	$324	$597,165	$437	$224	$597,826
	Intersegment Revenues	$6,396	$23,712	$—	$208	$7,898	$38,214	$—	($38,214)	$—
	Segment Profit: Net Income (Loss)	$34,516	$16,796	$27,711	$4,283	$3,093	$86,399	($29)	($650)	$85,720
	Six Months Ended March 31, 2013 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$511,953	$89,842	$323,529	$123,154	$526	$1,049,004	$1,252	$424	$1,050,680
	Intersegment Revenues	$10,707	$46,509	$—	$634	$13,377	$71,227	$—	($71,227)	$—
	Segment Profit: Net Income (Loss)	$57,394	$33,728	$54,391	$4,778	$5,035	$155,326	($85)	($1,577)	$153,664

Retirement_Plan_And_Other_Post

Retirement Plan And Other Post-Retirement Benefits	6 Months Ended
	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]	'
Retirement Plan and Other Post-Retirement Benefits	'
	Retirement Plan and Other Post-Retirement Benefits
	Components of Net Periodic Benefit Cost (in thousands):
		Retirement Plan						Other Post-Retirement Benefits
	Three Months Ended March 31,	2014			2013			2014			2013
	Service Cost	$	2,997		$	3,961		$	735		$	1,176
	Interest Cost	10,893			9,124			5,327			4,803
	Expected Return on Plan Assets	(14,993		)	(14,336		)	(9,356		)	(8,218		)
	Amortization of Prior Service Cost (Credit)	52			60			(534		)	(534		)
	Amortization of Transition Amount	—			—			—			2
	Amortization of Losses	9,002			13,194			661			5,223
	Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	8,557			1,724			7,928			6,459
	Net Periodic Benefit Cost	$	16,508		$	13,727		$	4,761		$	8,911
		Retirement Plan						Other Post-Retirement Benefits
	Six Months Ended March 31,	2014			2013			2014			2013
	Service Cost	$	5,993		$	7,923		$	1,469		$	2,352
	Interest Cost	21,787			18,249			10,654			9,606
	Expected Return on Plan Assets	(29,986		)	(28,673		)	(18,712		)	(16,436		)
	Amortization of Prior Service Cost (Credit)	105			119			(1,069		)	(1,069		)
	Amortization of Transition Amount	—			—			—			4
	Amortization of Losses	18,003			26,388			1,323			10,446
	Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	10,135			(1,958		)	13,988			9,162
	Net Periodic Benefit Cost	$	26,037		$	22,048		$	7,653		$	14,065
	(1) The Company’s policy is to record retirement plan and other post-retirement benefit costs in the Utility segment on a volumetric basis to reflect the fact that the Utility segment experiences higher throughput of natural gas in the winter months and lower throughput of natural gas in the summer months.
	Employer Contributions.    During the six months ended March 31, 2014, the Company contributed $30.0 million to its tax-qualified, noncontributory defined-benefit retirement plan (Retirement Plan) and $2.0 million to its VEBA trusts and 401(h) accounts for its other post-retirement benefits.  In the remainder of 2014, the Company expects its contributions to the Retirement Plan to be in the range of zero to $5.0 million.  Changes in the discount rate, other actuarial assumptions, and asset performance could ultimately cause the Company to fund larger amounts to the Retirement Plan in fiscal 2014 in order to be in compliance with the Pension Protection Act of 2006 (as impacted by the Moving Ahead for Progress in the 21st Century Act).  In July 2012, the Surface Transportation Extension Act, which is also referred to as the Moving Ahead for Progress in the 21st Century Act (the Act), was passed by Congress and signed by the President.  The Act included pension funding stabilization provisions.  The Company is continually evaluating its future contributions in light of the provisions of the Act. In the remainder of 2014, the Company expects its contributions to its VEBA trusts and 401(h) accounts to be in the range of zero to $10.0 million.

Regulatory_Matters

Regulatory Matters	6 Months Ended
	Mar. 31, 2014
Regulatory Assets and Liabilities, Other Disclosures [Abstract]	'
Regulatory Matters	'
	Regulatory Matters
	Following discussions with regulatory staff with respect to earnings levels, on March 27, 2013, Distribution Corporation filed a plan (“Plan”) with the NYPSC proposing to adopt an “earnings stabilization and sharing mechanism” that would allocate earnings above a rate of return on equity of 9.96% evenly between shareholders and an accounting reserve (“Reserve”).  The Reserve would be utilized to stabilize Distribution Corporation’s earnings and to fund customer benefit programs.  The Plan also proposed to increase capital spending and to aid new customer system expansion efforts.  Discussions were held with NYPSC staff and others with respect to the Plan.
	Subsequently, on April 19, 2013, the NYPSC issued an order directing Distribution Corporation to either agree to make its rates and charges temporary subject to refund effective June 1, 2013, or show cause why its gas rates and charges should not be set on a temporary basis subject to refund (“Order”).  The Order recognized Distribution Corporation’s Plan and, while acknowledging the Company’s cost-cutting and efficiency achievements, determined nonetheless that the Plan did not propose to adjust “existing rates . . . enough to compensate for the imbalance between ratepayer and shareholder interests that has developed since . . . 2007 . . .”  Pursuant to the Order, the NYPSC commenced a “temporary rate” proceeding and, following hearings, on June 14, 2013, the NYPSC issued an order (“Temporary Rates Order”) making Distribution Corporation’s rates and charges temporary and subject to refund pending the determination of permanent gas rates through further rate proceedings.  Discussions for settlement of Distribution Corporation’s rates and charges were commenced while the formal case to establish permanent rates proceeded along a parallel path.
	In addition to authorizing a “temporary rate” proceeding, the Order also suggested an examination of the applicability of a provision of New York public utility law, PSL §66(20), that provides the NYPSC with stated authority to direct a refund of revenues received by a utility “in excess of its authorized rate of return for a period of twelve months.” On May 17, 2013, Distribution Corporation commenced an action in New York Supreme Court, Erie County, seeking the court’s declaration that PSL §66(20) is unconstitutional.  On October 25, 2013, the court dismissed Distribution Corporation’s complaint without prejudice to recommence the action after a decision is rendered in the rate proceeding before the NYPSC.  In addition, on September 25, 2013, Distribution Corporation commenced an appeal in New York Supreme Court, Albany County, seeking to annul the Temporary Rates Order on various grounds.
	On December 6, 2013, Distribution Corporation filed an agreement, executed by five of the six active parties in the rate proceeding, for settlement of the temporary rate proceeding and all issues relating to rates.  The settlement agreement proposes to fix customer rates at existing levels for a minimum two-year term retroactive to October 1, 2013.  Although customer rates are fixed, the parties agreed that the allowed rate of return on equity would be set, for ratemaking purposes, at 9.1%.  Following conventional practice in New York, the agreement also proposes an “earnings sharing mechanism” (“ESM”).  The ESM distributes earnings above the allowed rate of return as follows:  from 9.5% to 10.5%, 50% would be allocated to shareholders, and 50% will be deferred for the benefit of customers; above 10.5%, 20% would be allocated to shareholders and 80% will be deferred for the benefit of customers.  The agreement further authorizes, and rates reflect, an increase in Distribution Corporation’s pipeline replacement spending by $8.2 million per year.  The agreement contains other terms and conditions of service that are customary for settlement agreements recently approved by the NYPSC.  The Consolidated Balance Sheets at March 31, 2014 and September 30, 2013 reflect a $7.5 million refund provision related to the settlement agreement.
	Signatory parties also filed statements with the NYPSC requesting approval of the settlement agreement without modification.  One special-interest consumer advocate is opposing the settlement agreement.  Following further proceedings, the NYPSC approved the settlement agreement at a regular session held in May 2014.

Summary_Of_Significant_Account1

Summary Of Significant Accounting Policies (Policy)	6 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Principles Of Consolidation	'
	Principles of Consolidation.  The Company consolidates all entities in which it has a controlling financial interest.  All significant intercompany balances and transactions are eliminated.
	The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.  Actual results could differ from those estimates.
Reclassifications	'
	Reclassifications.  Certain prior year amounts have been reclassified to conform with current year presentation.
Earnings For Interim Periods	'
	Earnings for Interim Periods.  The Company, in its opinion, has included all adjustments (which consist of only normally recurring adjustments, unless otherwise disclosed in this Form 10-Q) that are necessary for a fair statement of the results of operations for the reported periods. The consolidated financial statements and notes thereto, included herein, should be read in conjunction with the financial statements and notes for the years ended September 30, 2013, 2012 and 2011 that are included in the Company's 2013 Form 10-K.  The consolidated financial statements for the year ended September 30, 2014 will be audited by the Company's independent registered public accounting firm after the end of the fiscal year.
	The earnings for the six months ended March 31, 2014 should not be taken as a prediction of earnings for the entire fiscal year ending September 30, 2014.  Most of the business of the Utility and Energy Marketing segments is seasonal in nature and is influenced by weather conditions.  Due to the seasonal nature of the heating business in the Utility and Energy Marketing segments, earnings during the winter months normally represent a substantial part of the earnings that those segments are expected to achieve for the entire fiscal year.  The Company’s business segments are discussed more fully in Note 7 – Business Segment Information.
Consolidated Statement Of Cash Flows	'
	Consolidated Statement of Cash Flows.  For purposes of the Consolidated Statement of Cash Flows, the Company considers all highly liquid debt instruments purchased with a maturity of generally three months or less to be cash equivalents.
Hedging Collateral Deposits	'
	Hedging Collateral Deposits.  This is an account title for cash held in margin accounts funded by the Company to serve as collateral for hedging positions.  At March 31, 2014, the Company had no hedging collateral deposits outstanding. At September 30, 2013, the Company had hedging collateral deposits of $1.1 million related to its exchange-traded futures contracts.  In accordance with its accounting policy, the Company does not offset hedging collateral deposits paid or received against related derivative financial instruments liability or asset balances.
Gas Stored Underground - Current	'
	Gas Stored Underground - Current.  In the Utility segment, gas stored underground – current is carried at lower of cost or market, on a LIFO method.  Gas stored underground – current normally declines during the first and second quarters of the year and is replenished during the third and fourth quarters.  In the Utility segment, the current cost of replacing gas withdrawn from storage is recorded in the Consolidated Statements of Income and a reserve for gas replacement is recorded in the Consolidated Balance Sheets under the caption “Other Accruals and Current Liabilities.”  Such reserve, which amounted to $73.9 million at March 31, 2014, is reduced to zero by September 30 of each year as the inventory is replenished.
Property, Plant and Equipment	'
	Property, Plant and Equipment.  In the Company’s Exploration and Production segment, oil and gas property acquisition, exploration and development costs are capitalized under the full cost method of accounting. Under this methodology, all costs associated with property acquisition, exploration and development activities are capitalized, including internal costs directly identified with acquisition, exploration and development activities. The internal costs that are capitalized do not include any costs related to production, general corporate overhead, or similar activities. The Company does not recognize any gain or loss on the sale or other disposition of oil and gas properties unless the gain or loss would significantly alter the relationship between capitalized costs and proved reserves of oil and gas attributable to a cost center.
	Capitalized costs include costs related to unproved properties, which are excluded from amortization until proved reserves are found or it is determined that the unproved properties are impaired.  Such costs amounted to $184.5 million and $106.1 million at March 31, 2014 and September 30, 2013, respectively.  All costs related to unproved properties are reviewed quarterly to determine if impairment has occurred. The amount of any impairment is transferred to the pool of capitalized costs being amortized.
	Capitalized costs are subject to the SEC full cost ceiling test. The ceiling test, which is performed each quarter, determines a limit, or ceiling, on the amount of property acquisition, exploration and development costs that can be capitalized. The ceiling under this test represents (a) the present value of estimated future net cash flows, excluding future cash outflows associated with settling asset retirement obligations that have been accrued on the balance sheet, using a discount factor of 10%, which is computed by applying prices of oil and gas (as adjusted for hedging) to estimated future production of proved oil and gas reserves as of the date of the latest balance sheet, less estimated future expenditures, plus (b) the cost of unevaluated properties not being depleted, less (c) income tax effects related to the differences between the book and tax basis of the properties. The natural gas and oil prices used to calculate the full cost ceiling are based on an unweighted arithmetic average of the first day of the month oil and gas prices for each month within the twelve-month period prior to the end of the reporting period. If capitalized costs, net of accumulated depreciation, depletion and amortization and related deferred income taxes, exceed the ceiling at the end of any quarter, a permanent impairment is required to be charged to earnings in that quarter.  At March 31, 2014, the ceiling exceeded the book value of the oil and gas properties by approximately $204.0 million.
Accumulated Other Comprehensive Income (Loss)	'
	Accumulated Other Comprehensive Loss.  The components of Accumulated Other Comprehensive Loss and changes for the quarter and six months ended March 31, 2014, net of related tax effect, are as follows (amounts in parentheses indicate debits) (in thousands):
	Three Months Ended March 31, 2014
		Gains and Losses on Derivative Financial Instruments			Gains and Losses on Securities Available for Sale			Funded Status of the Pension and Other Post-Retirement Benefit Plans			Total
	Balance at January 1, 2014	$	26,345		$	7,910		$	(56,293	)	$	(22,038	)
	Other Comprehensive Gains and Losses Before Reclassifications	(38,878		)	391			—			(38,487		)
	Amounts Reclassified From Other Comprehensive Loss	15,470			—			—			15,470
	Balance at March 31, 2014	$	2,937		$	8,301		$	(56,293	)	$	(45,055	)
	Six Months Ended March 31, 2014
		Gains and Losses on Derivative Financial Instruments			Gains and Losses on Securities Available for Sale			Funded Status of the Pension and Other Post-Retirement Benefit Plans			Total
	Balance at October 1, 2013	$	30,722		$	6,337		$	(56,293	)	$	(19,234	)
	Other Comprehensive Gains and Losses Before Reclassifications	(37,370		)	1,964			—			(35,406		)
	Amounts Reclassified From Other Comprehensive Loss	9,585			—			—			9,585
	Balance at March 31, 2014	$	2,937		$	8,301		$	(56,293	)	$	(45,055	)
Reclassifications Out Of Accumulated Other Comprehensive Loss	'
	Reclassifications Out of Accumulated Other Comprehensive Loss.  The details about the reclassification adjustments out of accumulated other comprehensive loss for the quarter and six months ended March 31, 2014 are as follows (amounts in parentheses indicate debits to the income statement) (in thousands):
	Three Months Ended March 31, 2014
	Details About Accumulated Other Comprehensive Loss Components	Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Loss			Affected Line Item in the Statement Where Net Income is Presented
	Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges:
	Commodity Contracts		($22,611	)	Operating Revenues
	Commodity Contracts	(4,029		)	Purchased Gas
		(26,640		)	Total Before Income Tax
		11,170			Income Tax Expense
			($15,470	)	Net of Tax
	Six Months Ended March 31, 2014
	Details About Accumulated Other Comprehensive Loss Components	Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Loss			Affected Line Item in the Statement Where Net Income is Presented
	Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges:
	Commodity Contracts		($12,825	)	Operating Revenues
	Commodity Contracts	(3,632		)	Purchased Gas
		(16,457		)	Total Before Income Tax
		6,872			Income Tax Expense
			($9,585	)	Net of Tax
Other Current Assets	'
	Other Current Assets.  The components of the Company’s Other Current Assets are as follows (in thousands):
		At March 31, 2014				At September 30, 2013
	Prepayments	$	4,221			$	10,605
	Prepaid Property and Other Taxes	21,950				13,079
	Federal Income Taxes Receivable	—				1,122
	State Income Taxes Receivable	—				3,275
	Fair Values of Firm Commitments	—				1,829
	Regulatory Assets	28,732				26,995
		$	54,903			$	56,905
Other Accruals And Current Liabilities	'
	Other Accruals and Current Liabilities.  The components of the Company’s Other Accruals and Current Liabilities are as follows (in thousands):
		At March 31, 2014				At September 30, 2013
	Accrued Capital Expenditures	$	90,831			$	41,100
	Regulatory Liabilities	11,085				20,013
	Reserve for Gas Replacement	73,883				—
	Federal Income Taxes Payable	30,802				—
	State Income Taxes Payable	4,063				—
	Other	25,236				22,833
		$	235,900			$	83,946
Earnings Per Common Share	'
	Earnings Per Common Share.  Basic earnings per common share is computed by dividing net income available for common stock by the weighted average number of common shares outstanding for the period. Diluted earnings per common share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock.  For purposes of determining earnings per common share, the potentially dilutive securities the Company has outstanding are stock options, SARs, restricted stock units and performance shares.  The diluted weighted average shares outstanding shown on the Consolidated Statements of Income reflects the potential dilution as a result of these securities as determined using the Treasury Stock Method.  Stock options, SARs, restricted stock units and performance shares that are antidilutive are excluded from the calculation of diluted earnings per common share.  There were no securities excluded as being antidilutive for the quarter ended March 31, 2014. There were 265 securities excluded as being antidilutive for the six months ended March 31, 2014.  There were 208,819 and 362,681 securities excluded as being antidilutive for the quarter and six months ended March 31, 2013, respectively.
Stock-Based Compensation	'
	Stock-Based Compensation.  The Company granted 116,090 performance shares during the six months ended March 31, 2014. The weighted average fair value of such performance shares was $67.16 per share for the six months ended March 31, 2014. Performance shares are an award constituting units denominated in common stock of the Company, the number of which may be adjusted over a performance cycle based upon the extent to which performance goals have been satisfied.  Earned performance shares may be distributed in the form of shares of common stock of the Company, an equivalent value in cash or a combination of cash and shares of common stock of the Company, as determined by the Company. The performance shares do not entitle the participant to receive dividends during the vesting period.
	Half of the performance shares granted during the six months ended March 31, 2014 must meet a performance goal related to relative return on capital over the performance cycle of October 1, 2013 to September 30, 2016.  The performance goal over the performance cycle is the Company’s total return on capital relative to the total return on capital of other companies in a group selected by the Compensation Committee (“Report Group”).  Total return on capital for a given company means the average of the Report Group companies’ returns on capital for each twelve month period corresponding to each of the Company’s fiscal years during the performance cycle, based on data reported for the Report Group companies in the Bloomberg database.  The number of these performance shares that will vest and be paid will depend upon the Company’s performance relative to the Report Group and not upon the absolute level of return achieved by the Company.  The fair value of these performance shares is calculated by multiplying the expected number of shares that will be issued by the average market price of Company common stock on the date of grant reduced by the present value of forgone dividends over the vesting term of the award.  The fair value is recorded as compensation expense over the vesting term of the award.  The other half of the performance shares granted during the six months ended March 31, 2014 must meet a performance goal related to total shareholder return over the performance cycle of October 1, 2013 to September 30, 2016.  The performance goal over the performance cycle is the Company’s three-year total shareholder return relative to the three-year total shareholder return of the other companies in the Report Group.  Three-year shareholder return for a given company will be based on the data reported for that company (with the starting and ending stock prices over the performance cycle calculated as the average closing stock price for the prior calendar month and with dividends reinvested in that company’s securities at each ex-dividend date) in the Bloomberg database.  The number of these performance shares that will vest and be paid will depend upon the Company’s performance relative to the Report Group and not upon the absolute level of return achieved by the Company.  The fair value price at the date of grant for these performance shares is determined using a Monte Carlo simulation technique, which includes a reduction in value for the present value of forgone dividends over the vesting term of the award.  This price is multiplied by the number of performance shares awarded, the result of which is recorded as compensation expense over the vesting term of the award.
	The Company granted 80,951 non-performance based restricted stock units during the six months ended March 31, 2014.  The weighted average fair value of such non-performance based restricted stock units was $65.23 per share for the six months ended March 31, 2014. Restricted stock units represent the right to receive shares of common stock of the Company (or the equivalent value in cash or a combination of cash and shares of common stock of the Company, as determined by the Company) at the end of a specified time period. These non-performance based restricted stock units do not entitle the participant to receive dividends during the vesting period. The accounting for non-performance based restricted stock units is the same as the accounting for restricted share awards, except that the fair value at the date of grant of the restricted stock units must be reduced by the present value of forgone dividends over the vesting term of the award.
	No stock options, SARs or restricted share awards were granted by the Company during the six months ended March 31, 2014.

Summary_Of_Significant_Account2

Summary Of Significant Accounting Policies (Tables)	6 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Components Of Accumulated Other Comprehensive Income (Loss)	'
	The components of Accumulated Other Comprehensive Loss and changes for the quarter and six months ended March 31, 2014, net of related tax effect, are as follows (amounts in parentheses indicate debits) (in thousands):
	Three Months Ended March 31, 2014
		Gains and Losses on Derivative Financial Instruments			Gains and Losses on Securities Available for Sale			Funded Status of the Pension and Other Post-Retirement Benefit Plans			Total
	Balance at January 1, 2014	$	26,345		$	7,910		$	(56,293	)	$	(22,038	)
	Other Comprehensive Gains and Losses Before Reclassifications	(38,878		)	391			—			(38,487		)
	Amounts Reclassified From Other Comprehensive Loss	15,470			—			—			15,470
	Balance at March 31, 2014	$	2,937		$	8,301		$	(56,293	)	$	(45,055	)
	Six Months Ended March 31, 2014
		Gains and Losses on Derivative Financial Instruments			Gains and Losses on Securities Available for Sale			Funded Status of the Pension and Other Post-Retirement Benefit Plans			Total
	Balance at October 1, 2013	$	30,722		$	6,337		$	(56,293	)	$	(19,234	)
	Other Comprehensive Gains and Losses Before Reclassifications	(37,370		)	1,964			—			(35,406		)
	Amounts Reclassified From Other Comprehensive Loss	9,585			—			—			9,585
	Balance at March 31, 2014	$	2,937		$	8,301		$	(56,293	)	$	(45,055	)
Schedule Of Reclassifications Out Of Accumulated Other Comprehensive Loss	'
	The details about the reclassification adjustments out of accumulated other comprehensive loss for the quarter and six months ended March 31, 2014 are as follows (amounts in parentheses indicate debits to the income statement) (in thousands):
	Three Months Ended March 31, 2014
	Details About Accumulated Other Comprehensive Loss Components	Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Loss			Affected Line Item in the Statement Where Net Income is Presented
	Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges:
	Commodity Contracts		($22,611	)	Operating Revenues
	Commodity Contracts	(4,029		)	Purchased Gas
		(26,640		)	Total Before Income Tax
		11,170			Income Tax Expense
			($15,470	)	Net of Tax
	Six Months Ended March 31, 2014
	Details About Accumulated Other Comprehensive Loss Components	Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Loss			Affected Line Item in the Statement Where Net Income is Presented
	Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges:
	Commodity Contracts		($12,825	)	Operating Revenues
	Commodity Contracts	(3,632		)	Purchased Gas
		(16,457		)	Total Before Income Tax
		6,872			Income Tax Expense
			($9,585	)	Net of Tax
Schedule Of Other Current Assets	'
	The components of the Company’s Other Current Assets are as follows (in thousands):
		At March 31, 2014				At September 30, 2013
	Prepayments	$	4,221			$	10,605
	Prepaid Property and Other Taxes	21,950				13,079
	Federal Income Taxes Receivable	—				1,122
	State Income Taxes Receivable	—				3,275
	Fair Values of Firm Commitments	—				1,829
	Regulatory Assets	28,732				26,995
		$	54,903			$	56,905
Schedule Of Other Accruals And Current Liabilities	'
	The components of the Company’s Other Accruals and Current Liabilities are as follows (in thousands):
		At March 31, 2014				At September 30, 2013
	Accrued Capital Expenditures	$	90,831			$	41,100
	Regulatory Liabilities	11,085				20,013
	Reserve for Gas Replacement	73,883				—
	Federal Income Taxes Payable	30,802				—
	State Income Taxes Payable	4,063				—
	Other	25,236				22,833
		$	235,900			$	83,946

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	6 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	'
	The following table sets forth, by level within the fair value hierarchy, the Company's financial assets and liabilities (as applicable) that were accounted for at fair value on a recurring basis as of March 31, 2014 and September 30, 2013.  Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.  The fair value presentation for over the counter swaps has been changed to combine gas and oil swaps at both March 31, 2014 and September 30, 2013.  In the September 30, 2013 Form 10-K, gas swaps were reported separately from oil swaps.  This change in presentation was made because a significant number of the counterparties enter into both gas and oil swap agreements with the Company.
	Recurring Fair Value Measures	At fair value as of March 31, 2014
	(Thousands of Dollars)	Level 1				Level 2				Level 3				Netting Adjustments(1)				Total(1)
	Assets:
	Cash Equivalents – Money Market Mutual Funds	$	129,892			$	—			$	—			$	—			$	129,892
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	3,297				—				—				(847		)		2,450
	Over the Counter Swaps – Gas and Oil	—				48,284				273				(25,230		)		23,327
	Other Investments:
	Balanced Equity Mutual Fund	34,407				—				—				—				34,407
	Common Stock – Financial Services Industry	7,631				—				—				—				7,631
	Other Common Stock	383				—				—				—				383
	Hedging Collateral Deposits	—				—				—				—				—
	Total	$	175,610			$	48,284			$	273			$	(26,077	)		$	198,090
	Liabilities:
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	$	847			$	—			$	—			$	(847	)		$	—
	Over the Counter Swaps – Gas and Oil	—				45,822				1,644				(25,230		)		22,236
	Total	$	847			$	45,822			$	1,644			$	(26,077	)		$	22,236
	Total Net Assets/(Liabilities)	$	174,763			$	2,462			$	(1,371	)		$	—			$	175,854
	Recurring Fair Value Measures	At fair value as of September 30, 2013
	(Thousands of Dollars)	Level 1				Level 2				Level 3				Netting Adjustments(1)				Total(1)
	Assets:
	Cash Equivalents – Money Market Mutual Funds	$	51,332			$	—			$	—			$	—			$	51,332
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	2,552				—				—				(1,641		)		911
	Over the Counter Swaps – Gas and Oil	—				57,070				—				(9,003		)		48,067
	Other Investments:
	Balanced Equity Mutual Fund	31,813				—				—				—				31,813
	Common Stock – Financial Services Industry	6,544				—				—				—				6,544
	Other Common Stock	330				—				—				—				330
	Hedging Collateral Deposits	1,094				—				—				—				1,094
	Total	$	93,665			$	57,070			$	—			$	(10,644	)		$	140,091
	Liabilities:
	Derivative Financial Instruments:
	Commodity Futures Contracts – Gas	$	1,641			$	—			$	—			$	(1,641	)		$	—
	Over the Counter Swaps – Gas and Oil	—				4,452				5,190				(9,003		)		639
	Total	$	1,641			$	4,452			$	5,190			$	(10,644	)		$	639
	Total Net Assets/(Liabilities)	$	92,024			$	52,618			$	(5,190	)		$	—			$	139,452
	(1)	Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.
Fair Value Measurements Using Unobservable Inputs (Level 3)	'
	All settlements of the derivative financial instruments are reflected in the Gains/Losses Realized and Included in Earnings column of the tables below (amounts in parentheses indicate credits in the derivative asset/liability accounts).
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Jan-14			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2014
	Derivative Financial Instruments(2)	$	(1,842	)	$	763		(1)	$	(292	)	$	—		$	(1,371	)
	(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2014.
	(2)	Derivative Financial Instruments are shown on a net basis.
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Oct-13			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2014
	Derivative Financial Instruments(2)	$	(5,190	)	$	1,043		(1)	$	2,776		$	—		$	(1,371	)
	(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the six months ended March 31, 2014.
	(2)	Derivative Financial Instruments are shown on a net basis.
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Jan-13			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2013
	Derivative Financial Instruments(2)	$	(14,089	)	$	4,539		(1)	$	(7,056	)	$	—		$	(16,606	)
	(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2013.
	(2)	Derivative Financial Instruments are shown on a net basis.
	Fair Value Measurements Using Unobservable Inputs (Level 3)
	(Thousands of Dollars)				Total Gains/Losses
		1-Oct-12			Gains/Losses Realized and Included in Earnings				Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)			Transfer In/Out of Level 3			March 31, 2013
	Derivative Financial Instruments(2)	$	(19,664	)	$	6,801		(1)	$	(3,743	)	$	—		$	(16,606	)
	(1)	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the six months ended March 31, 2013.
	(2)	Derivative Financial Instruments are shown on a net basis.

Financial_Instruments_Tables

Financial Instruments (Tables)	6 Months Ended
	Mar. 31, 2014
Financial Instruments, Owned, at Fair Value [Abstract]	'
Long-Term Debt	'
	Based on these criteria, the fair market value of long-term debt, including current portion, was as follows (in thousands):
		March 31, 2014								September 30, 2013
		Carrying Amount				Fair Value				Carrying Amount				Fair Value
	Long-Term Debt	$	1,649,000			$	1,787,823			$	1,649,000			$	1,767,519
Schedule Of Derivative Financial Instruments Designated And Qualifying As Cash Flow Hedges On The Statement Of Financial Performance	'
	The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the
	Three Months Ended March 31, 2014 and 2013 (Thousands of Dollars)
	Derivatives in Cash Flow Hedging Relationships	Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion) for the Three Months Ended March 31,						Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion) for the Three Months Ended March 31,						Location of Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing) for the Three Months Ended March 31,
		2014			2013				2014			2013				2014			2013
	Commodity Contracts - Exploration & Production segment	$	(64,237	)	$	(47,364	)	Operating Revenue	$	(22,611	)	$	11,285		Operating Revenue	$	(660	)	$	(456	)
	Commodity Contracts - Energy Marketing segment	$	(3,224	)	$	14		Purchased Gas	$	(4,029	)	$	(782	)	Not Applicable	$	—		$	—
	Commodity Contracts - Pipeline & Storage segment (1)	$	—		$	—		Operating Revenue	$	—		$	—		Not Applicable	$	—		$	—
	Total	$	(67,461	)	$	(47,350	)		$	(26,640	)	$	10,503			$	(660	)	$	(456	)
	The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the
	Six Months Ended March 31, 2014 and 2013 (Thousands of Dollars)
	Derivatives in Cash Flow Hedging Relationships	Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion) for the Six Months Ended March 31,						Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion) for the Six Months Ended March 31,						Location of Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing) for the Six Months Ended March 31,
		2014			2013				2014			2013				2014			2013
	Commodity Contracts - Exploration & Production segment	$	(59,117	)	$	(13,750	)	Operating Revenue	$	(12,825	)	$	23,590		Operating Revenue	$	774		$	(456	)
	Commodity Contracts - Energy Marketing segment	$	(5,565	)	$	1,749		Purchased Gas	$	(3,632	)	$	(830	)	Not Applicable	$	—		$	—
	Commodity Contracts - Pipeline & Storage segment (1)	$	—		$	—		Operating Revenue	$	—		$	(672	)	Not Applicable	$	—		$	—
	Total	$	(64,682	)	$	(12,001	)		$	(16,457	)	$	22,088			$	774		$	(456	)
	(1)	There were no open hedging positions at March 31, 2014 or 2013.
Schedule Of Derivatives And Hedged Items In Fair Value Hedging Relationships	'
	For derivative instruments that are designated and qualify as a fair value hedge, the gain or loss on the derivative as well as the offsetting gain or loss on the hedged item attributable to the hedged risk completely offset each other in current earnings, as shown below.
	Derivatives in Fair Value Hedging Relationships – Energy Marketing segment	Location of Gain or (Loss) on Derivative and Hedged Item Recognized in the Consolidated Statement of Income	Amount of Gain or (Loss) on Derivative Recognized in the Consolidated Statement of Income for the Six Months Ended March 31, 2014 (In Thousands)			Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income for the Six Months Ended March 31, 2014 (In Thousands)
	Commodity Contracts – Hedge of fixed price sales commitments of natural gas	Operating Revenues	$	3,779		$	(3,779	)
	Commodity Contracts – Hedge of fixed price purchase commitments of natural gas	Purchased Gas	$	(440	)	$	440
	Commodity Contracts – Hedge of natural gas held in storage	Purchased Gas	$	(38	)	$	38
			$	3,301		$	(3,301	)

Income_Taxes_Tables

Income Taxes (Tables)	6 Months Ended
	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Components Of Federal And State Income Taxes Included In The Consolidated Statements Of Income	'
	The components of federal and state income taxes included in the Consolidated Statements of Income are as follows (in thousands):
		Six Months Ended
		March 31,
		2014			2013
	Current Income Taxes
	Federal	$	39,974		$	(6,318	)
	State	9,607			2,496
	Deferred Income Taxes
	Federal	50,110			82,788
	State	21,829			19,769
		121,520			98,735
	Deferred Investment Tax Credit	(218		)	(213		)
	Total Income Taxes	$	121,302		$	98,522
	Presented as Follows:
	Other Income	(218		)	(213		)
	Income Tax Expense	121,520			98,735
	Total Income Taxes	$	121,302		$	98,522
Schedule Of Income Tax Reconciliation By Applying Federal Income Tax Rate	'
	Total income taxes as reported differ from the amounts that were computed by applying the federal income tax rate to income before income taxes.  The following is a reconciliation of this difference (in thousands):
		Six Months Ended
		March 31,
		2014			2013
	U.S. Income Before Income Taxes	$	298,765		$	252,186
	Income Tax Expense, Computed at U.S. Federal Statutory Rate of 35%	$	104,568		$	88,265
	Increase (Reduction) in Taxes Resulting from:
	State Income Taxes	20,433			14,473
	Miscellaneous	(3,699		)	(4,216		)
	Total Income Taxes	$	121,302		$	98,522
Significant Components Of Deferred Tax Liabilities And Assets	'
	Significant components of the Company’s deferred tax liabilities and assets were as follows (in thousands):
		At March 31, 2014			At September 30, 2013
	Deferred Tax Liabilities:
	Property, Plant and Equipment	$	1,551,701		$	1,504,187
	Pension and Other Post-Retirement Benefit Costs	121,780			124,021
	Other	55,562			75,419
	Total Deferred Tax Liabilities	1,729,043			1,703,627
	Deferred Tax Assets:
	Pension and Other Post-Retirement Benefit Costs	(132,752		)	(130,256		)
	Tax Loss Carryforwards	(184,123		)	(215,262		)
	Other	(99,087		)	(90,461		)
	Total Deferred Tax Assets	(415,962		)	(435,979		)
	Total Net Deferred Income Taxes	$	1,313,081		$	1,267,648
	Presented as Follows:
	Net Deferred Tax Liability/(Asset) – Current	(39,650		)	(79,359		)
	Net Deferred Tax Liability – Non-Current	1,352,731			1,347,007
	Total Net Deferred Income Taxes	$	1,313,081		$	1,267,648

Business_Segment_Information_T

Business Segment Information (Tables)	6 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Financial Segment Information By Segment	'
	Quarter Ended March 31, 2014 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$377,647	$53,571	$199,561	$124,439	$195	$755,413	$597	$232	$756,242
	Intersegment Revenues	$8,204	$22,235	$—	$5	$15,452	$45,896	$—	($45,896)	$—
	Segment Profit: Net Income	$35,545	$21,372	$24,390	$3,765	$7,324	$92,396	$278	$2,537	$95,211
	Six Months Ended March 31, 2014 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$608,100	$104,784	$392,607	$197,598	$429	$1,303,518	$2,298	$498	$1,306,314
	Intersegment Revenues	$12,911	$42,974	$—	$260	$29,802	$85,947	$—	($85,947)	$—
	Segment Profit: Net Income	$59,760	$40,510	$55,487	$5,369	$13,471	$174,597	$954	$1,912	$177,463
	(Thousands)	Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Segment Assets:
	At March 31, 2014	$2,019,438	$1,283,654	$2,821,355	$110,285	$247,286	$6,482,018	$95,849	($10,672)	$6,567,195
	At September 30, 2013	$1,870,587	$1,246,027	$2,746,233	$67,267	$203,323	$6,133,437	$95,793	($10,883)	$6,218,347
	Quarter Ended March 31, 2013 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$303,389	$46,383	$168,080	$78,989	$324	$597,165	$437	$224	$597,826
	Intersegment Revenues	$6,396	$23,712	$—	$208	$7,898	$38,214	$—	($38,214)	$—
	Segment Profit: Net Income (Loss)	$34,516	$16,796	$27,711	$4,283	$3,093	$86,399	($29)	($650)	$85,720
	Six Months Ended March 31, 2013 (Thousands)
		Utility	Pipeline and Storage	Exploration and Production	Energy Marketing	Gathering	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
	Revenue from External Customers	$511,953	$89,842	$323,529	$123,154	$526	$1,049,004	$1,252	$424	$1,050,680
	Intersegment Revenues	$10,707	$46,509	$—	$634	$13,377	$71,227	$—	($71,227)	$—
	Segment Profit: Net Income (Loss)	$57,394	$33,728	$54,391	$4,778	$5,035	$155,326	($85)	($1,577)	$153,664

Retirement_Plan_And_Other_Post1

Retirement Plan And Other Post-Retirement Benefits (Tables)	6 Months Ended
	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]	'
Components of Net Periodic Benefit Cost	'
	Components of Net Periodic Benefit Cost (in thousands):
		Retirement Plan						Other Post-Retirement Benefits
	Three Months Ended March 31,	2014			2013			2014			2013
	Service Cost	$	2,997		$	3,961		$	735		$	1,176
	Interest Cost	10,893			9,124			5,327			4,803
	Expected Return on Plan Assets	(14,993		)	(14,336		)	(9,356		)	(8,218		)
	Amortization of Prior Service Cost (Credit)	52			60			(534		)	(534		)
	Amortization of Transition Amount	—			—			—			2
	Amortization of Losses	9,002			13,194			661			5,223
	Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	8,557			1,724			7,928			6,459
	Net Periodic Benefit Cost	$	16,508		$	13,727		$	4,761		$	8,911
		Retirement Plan						Other Post-Retirement Benefits
	Six Months Ended March 31,	2014			2013			2014			2013
	Service Cost	$	5,993		$	7,923		$	1,469		$	2,352
	Interest Cost	21,787			18,249			10,654			9,606
	Expected Return on Plan Assets	(29,986		)	(28,673		)	(18,712		)	(16,436		)
	Amortization of Prior Service Cost (Credit)	105			119			(1,069		)	(1,069		)
	Amortization of Transition Amount	—			—			—			4
	Amortization of Losses	18,003			26,388			1,323			10,446
	Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1)	10,135			(1,958		)	13,988			9,162
	Net Periodic Benefit Cost	$	26,037		$	22,048		$	7,653		$	14,065
	(1) The Company’s policy is to record retirement plan and other post-retirement benefit costs in the Utility segment on a volumetric basis to reflect the fact that the Utility segment experiences higher throughput of natural gas in the winter months and lower throughput of natural gas in the summer months.

Summary_Of_Significant_Account3

Summary Of Significant Accounting Policies (Narrative) (Details) (USD $)

3 Months Ended

6 Months Ended

12 Months Ended

6 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Sep. 30, 2013

Mar. 31, 2014

Sep. 30, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Sep. 30, 2013

Sep. 30, 2014

Reserve For Gas Replacement [Member]

Reserve For Gas Replacement [Member]

Stock Options [Member]

Restricted Shares [Member]

Stock Appreciation Right [Member]

Non-performance Based Restricted Stock Units [Member]

Performance Shares [Member]

Exchange Traded Futures Contracts [Member]

Exchange Traded Futures Contracts [Member]

Subsequent Event [Member]

Reserve For Gas Replacement [Member]

Summary Of Significant Accounting Policies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Hedging collateral deposits

$0

[1]

'

$0

[1]

'

$1,094,000

[1]

'

'

'

'

'

'

'

$0

$1,100,000

'

Gas stored underground - current

-3,176,000

'

-3,176,000

'

-51,484,000

73,883,000

0

'

'

'

'

'

'

'

0

Capitalized costs of unproved properties excluded from amortization

'

'

184,500,000

'

106,100,000

'

'

'

'

'

'

'

'

'

'

Full cost ceiling test discount factor

10.00%

'

10.00%

'

'

'

'

'

'

'

'

'

'

'

'

Amount full cost ceiling exceeds book value of oil and gas properties

$204,000,000

'

$204,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Antidilutive securities

0

208,819

265

362,681

'

'

'

'

'

'

'

'

'

'

'

Share based compensation other than options grants in period

'

'

'

'

'

'

'

'

0

0

80,951

116,090

'

'

'

Granted in fiscal year, weighted average grant date fair value

'

'

'

'

'

'

'

'

'

'

$65.23

$67.16

'

'

'

Stock options granted

'

'

'

'

'

'

'

0

'

'

'

'

'

'

'

[1]

Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.

Summary_Of_Significant_Account4

Summary Of Significant Accounting Policies (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $)	3 Months Ended	6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2014
Accumulated Other Comprehensive Income [Roll Forward]	'	'
Balance at Beginning of Period	($22,038)	($19,234)
Other Comprehensive Gains and Losses Before Reclassification	-38,487	-35,406
Amounts Reclassified From Other Comprehensive Loss	15,470	9,585
Balance at End of Period	-45,055	-45,055
Gains And Losses On Derivative Financial Instruments [Member]	'	'
Accumulated Other Comprehensive Income [Roll Forward]	'	'
Balance at Beginning of Period	26,345	30,722
Other Comprehensive Gains and Losses Before Reclassification	-38,878	-37,370
Amounts Reclassified From Other Comprehensive Loss	15,470	9,585
Balance at End of Period	2,937	2,937
Gains And Losses On Securities Available For Sale [Member]	'	'
Accumulated Other Comprehensive Income [Roll Forward]	'	'
Balance at Beginning of Period	7,910	6,337
Other Comprehensive Gains and Losses Before Reclassification	391	1,964
Amounts Reclassified From Other Comprehensive Loss	0	0
Balance at End of Period	8,301	8,301
Funded Status Of The Pension And Other Post-Retirement Benefit Plans [Member]	'	'
Accumulated Other Comprehensive Income [Roll Forward]	'	'
Balance at Beginning of Period	-56,293	-56,293
Other Comprehensive Gains and Losses Before Reclassification	0	0
Amounts Reclassified From Other Comprehensive Loss	0	0
Balance at End of Period	($56,293)	($56,293)

Summary_Of_Significant_Account5

Summary Of Significant Accounting Policies (Reclassification Out Of Accumulated Other Comprehensive Loss) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Operating Revenues	$756,242	$597,826	$1,306,314	$1,050,680
Purchased Gas	-322,772	-209,817	-490,378	-331,735
Income Before Income Taxes	161,306	140,906	298,983	252,399
Income Tax Expense	-66,095	-55,186	-121,520	-98,735
Net Income Available for Common Stock	95,211	85,720	177,463	153,664
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Gains And Losses On Derivative Financial Instruments [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Income Before Income Taxes	-26,640	'	-16,457	'
Income Tax Expense	11,170	'	6,872	'
Net Income Available for Common Stock	-15,470	'	-9,585	'
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Commodity Contracts [Member] | Gains And Losses On Derivative Financial Instruments [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Operating Revenues	-22,611	'	-12,825	'
Purchased Gas	($4,029)	'	($3,632)	'

Summary_Of_Significant_Account6

Summary Of Significant Accounting Policies (Components Of Other Current Assets) (Details) (USD $)	Mar. 31, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Summary Of Significant Accounting Policies [Line Items]	'	'
Prepayments	$4,221	$10,605
Prepaid Property and Other Taxes	21,950	13,079
Fair Values of Firm Commitments	0	1,829
Regulatory Assets	28,732	26,995
Other Current Assets	54,903	56,905
Federal [Member]	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'
Income Taxes Receivable	0	1,122
State [Member]	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'
Income Taxes Receivable	$0	$3,275

Summary_Of_Significant_Account7

Summary Of Significant Accounting Policies (Schedule Of Other Accruals And Current Liabilities) (Details) (USD $)	Mar. 31, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Segment Reporting Information [Line Items]	'	'
Regulatory Liabilities	$11,085	$20,013
Reserve for Gas Replacement	-3,176	-51,484
Other	25,236	22,833
Other Accruals and Current Liabilities	235,900	83,946
Accrued Capital Expenditures [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Other	90,831	41,100
Reserve For Gas Replacement [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Reserve for Gas Replacement	73,883	0
Federal [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Income Taxes Payable	30,802	0
State [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Income Taxes Payable	$4,063	$0

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Details) (USD $)	6 Months Ended
	Mar. 31, 2014		Sep. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Hedging collateral deposits	$0	[1]	$1,094,000	[1]
Assumed 12 month basis differential comparison to NYMEX	100.30%		'
Assumed 12 month minimum basis differential comparison to NYMEX	96.20%		'
Assumed 12 month maximum basis differential comparison to NYMEX	108.10%		'
Fair value measured on recurring basis, net	175,854,000	[1]	139,452,000	[1]
Fair Value, Inputs, Level 1 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Hedging collateral deposits	0		1,094,000
Fair value measured on recurring basis, net	174,763,000		92,024,000
Fair Value, Inputs, Level 1 [Member] | NYMEX Futures [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Hedging collateral deposits	'		1,100,000
Fair Value, Inputs, Level 3 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Hedging collateral deposits	0		0
Fair value measured on recurring basis, net	-1,371,000		-5,190,000
Fair Value, Inputs, Level 3 [Member] | Over The Counter Swaps - Oil [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Fair value measured on recurring basis, net	1,400,000		'
Higher [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Derivative Basis Differential On NYMEX Sensitivity	10.00%		'
Higher [Member] | Fair Value, Inputs, Level 3 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Fair value of crude oil price swap sensitivity	5,800,000		'
Lower [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Derivative Basis Differential On NYMEX Sensitivity	10.00%		'
Lower [Member] | Fair Value, Inputs, Level 3 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Fair value of crude oil price swap sensitivity	$4,400,000		'
[1]	Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.

Fair_Value_Measurements_Recurr

Fair Value Measurements (Recurring Fair Value Measures Of Assets And Liabilities) (Details) (USD $)	Mar. 31, 2014		Sep. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Cash Equivalents - Money Market Mutual Funds	$129,892,000	[1]	$51,332,000	[1]
Hedging Collateral Deposits	0	[1]	1,094,000	[1]
Total Assets	198,090,000	[1]	140,091,000	[1]
Total Liabilities	22,236,000	[1]	639,000	[1]
Total Net Assets/(Liabilities)	175,854,000	[1]	139,452,000	[1]
Commodity Futures Contracts - Gas [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	2,450,000	[1]	911,000	[1]
Derivative Financial Instruments	0	[1]	0	[1]
Over The Counter Swaps - Gas And Oil [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	23,327,000	[1]	48,067,000	[1]
Derivative Financial Instruments	22,236,000	[1]	639,000	[1]
Balanced Equity Mutual Fund [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	34,407,000	[1]	31,813,000	[1]
Common Stock - Financial Services Industry [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	7,631,000	[1]	6,544,000	[1]
Other Common Stock [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	383,000	[1]	330,000	[1]
Fair Value, Inputs, Level 1 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Cash Equivalents - Money Market Mutual Funds	129,892,000		51,332,000
Hedging Collateral Deposits	0		1,094,000
Total Assets	175,610,000		93,665,000
Total Liabilities	847,000		1,641,000
Total Net Assets/(Liabilities)	174,763,000		92,024,000
Fair Value, Inputs, Level 1 [Member] | Commodity Futures Contracts - Gas [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	3,297,000		2,552,000
Derivative Financial Instruments	847,000		1,641,000
Fair Value, Inputs, Level 1 [Member] | Over The Counter Swaps - Gas And Oil [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	0		0
Derivative Financial Instruments	0		0
Fair Value, Inputs, Level 1 [Member] | Balanced Equity Mutual Fund [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	34,407,000		31,813,000
Fair Value, Inputs, Level 1 [Member] | Common Stock - Financial Services Industry [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	7,631,000		6,544,000
Fair Value, Inputs, Level 1 [Member] | Other Common Stock [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	383,000		330,000
Fair Value, Inputs, Level 2 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Cash Equivalents - Money Market Mutual Funds	0		0
Hedging Collateral Deposits	0		0
Total Assets	48,284,000		57,070,000
Total Liabilities	45,822,000		4,452,000
Total Net Assets/(Liabilities)	2,462,000		52,618,000
Fair Value, Inputs, Level 2 [Member] | Commodity Futures Contracts - Gas [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	0		0
Derivative Financial Instruments	0		0
Fair Value, Inputs, Level 2 [Member] | Over The Counter Swaps - Gas And Oil [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	48,284,000		57,070,000
Derivative Financial Instruments	45,822,000		4,452,000
Fair Value, Inputs, Level 2 [Member] | Balanced Equity Mutual Fund [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0		0
Fair Value, Inputs, Level 2 [Member] | Common Stock - Financial Services Industry [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0		0
Fair Value, Inputs, Level 2 [Member] | Other Common Stock [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0		0
Fair Value, Inputs, Level 3 [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Cash Equivalents - Money Market Mutual Funds	0		0
Hedging Collateral Deposits	0		0
Total Assets	273,000		0
Total Liabilities	1,644,000		5,190,000
Total Net Assets/(Liabilities)	-1,371,000		-5,190,000
Fair Value, Inputs, Level 3 [Member] | Commodity Futures Contracts - Gas [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	0		0
Derivative Financial Instruments	0		0
Fair Value, Inputs, Level 3 [Member] | Over The Counter Swaps - Gas And Oil [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	273,000		0
Derivative Financial Instruments	1,644,000		5,190,000
Fair Value, Inputs, Level 3 [Member] | Balanced Equity Mutual Fund [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0		0
Fair Value, Inputs, Level 3 [Member] | Common Stock - Financial Services Industry [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0		0
Fair Value, Inputs, Level 3 [Member] | Other Common Stock [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0		0
Netting Adjustments [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Cash Equivalents - Money Market Mutual Funds	0	[1]	0	[1]
Hedging Collateral Deposits	0	[1]	0	[1]
Total Assets	-26,077,000	[1]	-10,644,000	[1]
Total Liabilities	-26,077,000	[1]	-10,644,000	[1]
Total Net Assets/(Liabilities)	0	[1]	0	[1]
Netting Adjustments [Member] | Commodity Futures Contracts - Gas [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	-847,000	[1]	-1,641,000	[1]
Derivative Financial Instruments	-847,000	[1]	-1,641,000	[1]
Netting Adjustments [Member] | Over The Counter Swaps - Gas And Oil [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Derivative Financial Instruments	-25,230,000	[1]	-9,003,000	[1]
Derivative Financial Instruments	-25,230,000	[1]	-9,003,000	[1]
Netting Adjustments [Member] | Balanced Equity Mutual Fund [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0	[1]	0	[1]
Netting Adjustments [Member] | Common Stock - Financial Services Industry [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	0	[1]	0	[1]
Netting Adjustments [Member] | Other Common Stock [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'		'
Other Investments	$0	[1]	$0	[1]
[1]	Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.

Fair_Value_Measurements_Fair_V

Fair Value Measurements (Fair Value Measurements Using Unobservable Inputs (Level 3)) (Details) (Derivative Financial Instruments [Member], USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2014		Mar. 31, 2013
Derivative Financial Instruments [Member]	'		'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Roll Forward]	'		'		'		'
Beginning Balance	($1,842)	[1]	($14,089)	[1]	($5,190)	[1]	($19,664)	[1]
Total Gains/Losses, Realized and Included in Earnings	763	[1],[2]	4,539	[1],[3]	1,043	[1],[4]	6,801	[1],[5]
Total Gains/Losses Unrealized and Included in Other Comprehensive Income (Loss)	-292	[1]	-7,056	[1]	2,776	[1]	-3,743	[1]
Transfer In/Out of Level 3	0	[1]	0	[1]	0	[1]	0	[1]
Ending Balance	($1,371)	[1],[4]	($16,606)	[1]	($1,371)	[1],[4]	($16,606)	[1]
[1]	Derivative Financial Instruments are shown on a net basis.
[2]	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2014
[3]	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the three months ended March 31, 2013.
[4]	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the six months ended March 31, 2014.
[5]	Amounts are reported in Operating Revenues in the Consolidated Statement of Income for the six months ended March 31, 2013.

Financial_Instruments_Narrativ

Financial Instruments (Narrative) (Details) (USD $)

Mar. 31, 2014

Sep. 30, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Sep. 30, 2013

Mar. 31, 2014

Sep. 30, 2013

Mar. 31, 2014

Sep. 30, 2013

Mar. 31, 2014

counterparty

Exploration And Production [Member]

Exploration And Production [Member]

Energy Marketing [Member]

Over-The-Counter Swap Position

Fixed Price Purchase Commitments MMCf [Member]

Fair Value Hedges MMCf [Member]

Fixed Price Sales Commitments MMCf [Member]

Natural Gas MMCf [Member]

Natural Gas MMCf [Member]

Natural Gas MMCf [Member]

Natural Gas MMCf [Member]

Crude Oil Bbls [Member]

Exchange Traded Futures Contracts [Member]

Exchange Traded Futures Contracts [Member]

Equity Mutual Fund [Member]

Equity Mutual Fund [Member]

Insurance Company Stock [Member]

Insurance Company Stock [Member]

Credit Risk Related Contingency Feature [Member]

Over Counter Swaps Oil [Member]

Energy Marketing [Member]

Energy Marketing [Member]

Energy Marketing [Member]

Exploration And Production [Member]

Energy Marketing [Member]

Energy Marketing [Member]

Energy Marketing [Member]

Exploration And Production [Member]

Over-The-Counter Swap Position

MMcf

MMcf

MMcf

Cash Flow Hedges Short Position [Member]

MMcf

Cash Flow Hedges Short Position [Member]

Cash Flow Hedges Long Position [Member]

Cash Flow Hedges Short Position [Member]

counterparty

MMcf

MMcf

MMcf

bbl

Derivative Instruments, Gain (Loss) [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash surrender value of life insurance

$43,400,000

$57,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

34,400,000

31,800,000

7,600,000

6,500,000

'

Gross unrealized gain

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,700,000

5,700,000

5,200,000

4,100,000

'

Nonmonetary notional amount of price risk cash flow hedge derivatives, natural gas

'

'

'

'

'

'

'

'

'

239,000

6,900

3,500

3,400

'

'

'

'

'

'

'

'

Nonmonetary notional amount of price risk cash flow hedge derivatives, crude oil

'

'

'

'

'

'

'

'

'

'

'

'

'

4,269,000

'

'

'

'

'

'

'

Net hedging gains/losses in accumulated other comprehensive income (loss)

'

'

4,800,000

'

200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

After tax net hedging gains (losses) in accumulated other comprehensive income (loss)

'

'

2,800,000

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Pre-Tax Net Hedging Gain (Losses) Reclassified Within Twelve Months

'

'

-31,500,000

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

After Tax Net Hedging Gains (Losses) Reclassified Within Twelve Months, less than $0.1 million for Energy Marketing Segment

'

'

-18,700,000

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Pre-Tax Net Hedging Gain (Losses) Reclassified After Twelve Months

'

'

36,300,000

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

After Tax Net Hedging Gains (Losses) Reclassified After Twelve Months

'

'

21,500,000

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Nonmonetary notional amount of price risk fair value hedge derivatives, natural gas

'

'

'

'

'

'

500

7,500

7,000

'

'

'

'

'

'

'

'

'

'

'

'

Derivative gain (loss)

'

'

'

-1,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of counterparties in which the company holds over-the-counter swap positions

15

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of counterparties in net gain position

4

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit risk exposure per counterparty

'

'

'

'

'

5,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Maximum credit risk exposure per counterparty

'

'

'

'

'

9,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Hedging collateral deposits

0

[1]

1,094,000

[1]

'

'

'

0

'

'

'

'

'

'

'

'

0

1,100,000

'

'

'

'

'

Number of counterparties with a common credit-risk related contingency

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

12

Fair market value of derivative asset with a credit-risk related contingency

22,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair market value of derivative liability with a credit-risk related contingency

$19,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

Netting Adjustments represent the impact of legally-enforceable master netting arrangements that allow the Company to net gain and loss positions held with the same counterparties. The net asset or net liability for each counterparty is recorded as an asset or liability on the Company’s balance sheet.

Financial_Instruments_LongTerm

Financial Instruments (Long-Term Debt) (Details) (USD $)	Mar. 31, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Financial Instruments, Owned, at Fair Value [Abstract]	'	'
Carrying Amount	$1,649,000	$1,649,000
Fair Value	$1,787,823	$1,767,519

Financial_Instruments_Schedule

Financial Instruments (Schedule Of Derivative Financial Instruments Designated And Qualifying As Cash Flow Hedges On The Statement Of Financial Performance) (Details) (USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2014		Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion)	($67,461)		($47,350)		($64,682)		($12,001)
Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	-26,640		10,503		-16,457		22,088
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	-660		-456		774		-456
Exploration And Production [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion)	-64,237		-47,364		-59,117		-13,750
Exploration And Production [Member] | Operating Revenues [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	-22,611		11,285		-12,825		23,590
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	-660		-456		774		-456
Energy Marketing [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion)	-3,224		14		-5,565		1,749
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0		0		0		0
Energy Marketing [Member] | Purchased Gas [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	-4,029		-782		-3,632		-830
Pipeline And Storage [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on the Consolidated Statement of Comprehensive Income (Loss) (Effective Portion)	0	[1]	0	[1]	0	[1]	0	[1]
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	[1]	0	[1]	0	[1]	0	[1]
Pipeline And Storage [Member] | Operating Revenues [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income (Effective Portion)	$0	[1]	$0	[1]	$0	[1]	($672)	[1]
[1]	There were no open hedging positions at March 31, 2014 or 2013.

Financial_Instruments_Schedule1

Financial Instruments (Schedule Of Derivatives And Hedged Items In Fair Value Hedging Relationships) (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]	'
Amount of Gain or (Loss) on the Derivative Recognized in the Consolidated Statement of Income	$3,301
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	-3,301
Operating Revenues [Member] | Fixed Price Sales Commitments Of Natural Gas [Member]	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Amount of Gain or (Loss) on the Derivative Recognized in the Consolidated Statement of Income	3,779
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	-3,779
Purchased Gas [Member] | Fixed Price Purchase Commitments Of Natural Gas [Member]	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Amount of Gain or (Loss) on the Derivative Recognized in the Consolidated Statement of Income	-440
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	440
Purchased Gas [Member] | Natural Gas Held in Storage [Member]	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Amount of Gain or (Loss) on the Derivative Recognized in the Consolidated Statement of Income	-38
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	$38

Income_Taxes_Narrative_Details

Income Taxes (Narrative) (Details) (USD $)	6 Months Ended		12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Sep. 30, 2013
Income Taxes [Line Items]	'	'	'
Tax benefit recorded from exercise of stock options	$3,100,000	'	$700,000
Tax Benefit Not Realized Due to Tax Loss Carryforward	36,400,000	'	36,400,000
Taxes refundable to customers	90,779,000	'	85,655,000
Recoverable future taxes	161,258,000	'	163,355,000
Amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate	2,000,000	'	'
Change in unrecognized tax benefits	2,000,000	'	'
Tax benefit from change in enacted rate	-21,829,000	-19,769,000	'
Deferred Income Taxes [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Taxes refundable to customers	90,800,000	'	85,700,000
Recoverable future taxes	161,300,000	'	163,400,000
State Tax Law Change [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Tax benefit from change in enacted rate	$2,800,000	'	'
New York State | State and Local Jurisdiction [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Corporate Tax Rate	7.10%	'	'
Effective January 1, 2016 [Member] | New York State | State and Local Jurisdiction [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Corporate Tax Rate	6.50%	'	'

Income_Taxes_Components_Of_Fed

Income Taxes (Components Of Federal And State Income Taxes Included In The Consolidated Statements Of Income) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Current Income Taxes [Abstract]	'	'	'	'
Federal	'	'	$39,974	($6,318)
State	'	'	9,607	2,496
Deferred Income Taxes [Abstract]	'	'	'	'
Federal	'	'	50,110	82,788
State	'	'	21,829	19,769
Income Tax Expense	66,095	55,186	121,520	98,735
Deferred Investment Tax Credit	'	'	-218	-213
Total Income Taxes	'	'	121,302	98,522
Presented as Follows [Abstract]	'	'	'	'
Other Income	'	'	-218	-213
Income Tax Expense	$66,095	$55,186	$121,520	$98,735

Income_Taxes_Schedule_Of_Incom

Income Taxes (Schedule Of Income Tax Reconciliation By Applying Federal Income Tax Rate) (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Income Tax Disclosure [Abstract]	'	'
U.S. Income Before Income Taxes	$298,765	$252,186
Income Tax Expense, Computed at U.S. Federal Statutory Rate of 35%	104,568	88,265
Increase (Reduction) in Taxes Resulting from State Income Taxes	20,433	14,473
Increase (Reduction) in Taxes Resulting From Miscellaneous	-3,699	-4,216
Total Income Taxes	$121,302	$98,522
Federal Statutory Rate	35.00%	35.00%

Income_Taxes_Significant_Compo

Income Taxes (Significant Components Of Deferred Tax Liabilities And Assets) (Details) (USD $)	Mar. 31, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Deferred Tax Liabilities [Abstract]	'	'
Property, Plant and Equipment	$1,551,701	$1,504,187
Pension and Other Post-Retirement Benefit Costs	121,780	124,021
Other	55,562	75,419
Total Deferred Tax Liabilities	1,729,043	1,703,627
Deferred Tax Assets [Abstract]	'	'
Pension and Other Post-Retirement Benefit Costs	-132,752	-130,256
Tax Loss Carryforwards	-184,123	-215,262
Other	-99,087	-90,461
Total Deferred Tax Assets	-415,962	-435,979
Total Net Deferred Income Taxes	1,313,081	1,267,648
Net Deferred Tax Liability/(Asset) - Current	-39,650	-79,359
Net Deferred Tax Liability - Non Current	$1,352,731	$1,347,007

Capitalization_Details

Capitalization (Details)	6 Months Ended
	Mar. 31, 2014
Debt Instrument [Line Items]	'
Common stock shares issued due to stock option exercises	301,793
Issue shares of common stock for the Direct Stock Purchase and Dividend Reinvestment Plan	47,943
Issue shares of common stock for the 401(k) plans	32,053
Shares tendered	79,606
Restricted Stock Units [Member]	'
Debt Instrument [Line Items]	'
Common stock issued	8,732
Board Of Directors [Member]	'
Debt Instrument [Line Items]	'
Common stock issued	7,712

Commitments_And_Contingencies_

Commitments And Contingencies (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014
Site Contingency [Line Items]	'
Estimated minimum liability for environmental remediation	$14.10
Rate recovery period	'13 years
Former Manufactured Gas Plant Site [Member]	'
Site Contingency [Line Items]	'
Estimated minimum liability for environmental remediation	$13

Business_Segment_Information_N

Business Segment Information (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
			segment
Segment Reporting Information [Line Items]	'	'	'	'
Number of reportable segments	'	'	5	'
Segment Profit: Net Income (Loss)	$95,211	$85,720	$177,463	$153,664
Energy Marketing [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Segment Profit: Net Income (Loss)	3,765	4,283	5,369	4,778
Energy Marketing [Member] | Unbilled Revenues [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue from External Customers	8,200	'	33,700	'
Energy Marketing [Member] | Margin [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Segment Profit: Net Income (Loss)	($400)	'	$900	'

Business_Segment_Information_F

Business Segment Information (Financial Segment Information By Segment) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Sep. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	$95,211	$85,720	$177,463	$153,664	'
Segment Assets	6,567,195	'	6,567,195	'	6,218,347
Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	756,242	597,826	1,306,314	1,050,680	'
Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	0	0	0	0	'
Utility [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	35,545	34,516	59,760	57,394	'
Segment Assets	2,019,438	'	2,019,438	'	1,870,587
Utility [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	377,647	303,389	608,100	511,953	'
Utility [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	8,204	6,396	12,911	10,707	'
Pipeline And Storage [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	21,372	16,796	40,510	33,728	'
Segment Assets	1,283,654	'	1,283,654	'	1,246,027
Pipeline And Storage [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	53,571	46,383	104,784	89,842	'
Pipeline And Storage [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	22,235	23,712	42,974	46,509	'
Exploration And Production [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	24,390	27,711	55,487	54,391	'
Segment Assets	2,821,355	'	2,821,355	'	2,746,233
Exploration And Production [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	199,561	168,080	392,607	323,529	'
Exploration And Production [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	0	0	0	0	'
Energy Marketing [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	3,765	4,283	5,369	4,778	'
Segment Assets	110,285	'	110,285	'	67,267
Energy Marketing [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	124,439	78,989	197,598	123,154	'
Energy Marketing [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	5	208	260	634	'
Gathering [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	7,324	3,093	13,471	5,035	'
Segment Assets	247,286	'	247,286	'	203,323
Gathering [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	195	324	429	526	'
Gathering [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	15,452	7,898	29,802	13,377	'
Total Reportable Segments [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	92,396	86,399	174,597	155,326	'
Segment Assets	6,482,018	'	6,482,018	'	6,133,437
Total Reportable Segments [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	755,413	597,165	1,303,518	1,049,004	'
Total Reportable Segments [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	45,896	38,214	85,947	71,227	'
All Other [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	278	-29	954	-85	'
Segment Assets	95,849	'	95,849	'	95,793
All Other [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	597	437	2,298	1,252	'
All Other [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	0	0	0	0	'
Corporate And Intersegment Eliminations [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Segment Profit: Net Income (Loss)	2,537	-650	1,912	-1,577	'
Segment Assets	-10,672	'	-10,672	'	-10,883
Corporate And Intersegment Eliminations [Member] | Revenue From External Customers [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	232	224	498	424	'
Corporate And Intersegment Eliminations [Member] | Intersegment Revenues [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Revenue	($45,896)	($38,214)	($85,947)	($71,227)	'

Retirement_Plan_And_Other_Post2

Retirement Plan And Other Post-Retirement Benefits (Narrative) (Details) (USD $)	6 Months Ended
	Mar. 31, 2014
Retirement Plan [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Company's contributions	$30,000,000
VEBA Trusts And 401(h) Accounts [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Company's contributions	2,000,000
Minimum [Member] | Retirement Plan [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Estimated future contributions in remainder of fiscal year	0
Minimum [Member] | VEBA Trusts And 401(h) Accounts [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Estimated future contributions in remainder of fiscal year	0
Maximum [Member] | Retirement Plan [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Estimated future contributions in remainder of fiscal year	5,000,000
Maximum [Member] | VEBA Trusts And 401(h) Accounts [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Estimated future contributions in remainder of fiscal year	$10,000,000

Retirement_Plan_And_Other_Post3

Retirement Plan And Other Post-Retirement Benefits (Components Of Net Periodic Benefit Cost) (Details) (USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2014		Mar. 31, 2013
Retirement Plan [Member]	'		'		'		'
Defined Benefit Plan Disclosure [Line Items]	'		'		'		'
Service Cost	$2,997		$3,961		$5,993		$7,923
Interest Cost	10,893		9,124		21,787		18,249
Expected Return on Plan Assets	-14,993		-14,336		-29,986		-28,673
Amortization of Prior Service Cost (Credit)	52		60		105		119
Amortization of Transition Amount	0		0		0		0
Amortization of Losses	9,002		13,194		18,003		26,388
Net Amortization and Deferral For Regulatory Purposes (Including Volumetric Adjustments)	8,557	[1]	1,724	[1]	10,135	[1]	-1,958	[1]
Net Periodic Benefit Cost	16,508		13,727		26,037		22,048
Other Post-Retirement Benefit Plans, Defined Benefit [Member]	'		'		'		'
Defined Benefit Plan Disclosure [Line Items]	'		'		'		'
Service Cost	735		1,176		1,469		2,352
Interest Cost	5,327		4,803		10,654		9,606
Expected Return on Plan Assets	-9,356		-8,218		-18,712		-16,436
Amortization of Prior Service Cost (Credit)	-534		-534		-1,069		-1,069
Amortization of Transition Amount	0		2		0		4
Amortization of Losses	661		5,223		1,323		10,446
Net Amortization and Deferral For Regulatory Purposes (Including Volumetric Adjustments)	7,928	[1]	6,459	[1]	13,988	[1]	9,162	[1]
Net Periodic Benefit Cost	$4,761		$8,911		$7,653		$14,065
[1]	The Company’s policy is to record retirement plan and other post-retirement benefit costs in the Utility segment on a volumetric basis to reflect the fact that the Utility segment experiences higher throughput of natural gas in the winter months and lower throughput of natural gas in the summer months.

Regulatory_Matters_Details

Regulatory Matters (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013	Mar. 27, 2013
Regulatory Matters [Line Items]	'	'	'
Proposed rate of return on equity	'	'	9.96%
Rate proceeding refund provision pre tax	$7.50	$7.50	'
Allowed rate of return on equity	9.10%	'	'
Authorized Increase in Distribution Corporation's pipeline relacement spending	$8.20	'	'
Maximum [Member]	'	'	'
Regulatory Matters [Line Items]	'	'	'
Allowed rate of return on equity range	10.50%	'	'
Minimum [Member]	'	'	'
Regulatory Matters [Line Items]	'	'	'
Allowed rate of return on equity range	9.50%	'	'
9.5 Percent To 10.5 Percent Rate Of Return On Equity [Member] | Shareholder Allocation [Member]	'	'	'
Regulatory Matters [Line Items]	'	'	'
Earnings sharing mechanism allocation of earnings	50.00%	'	'
9.5 Percent To 10.5 Percent Rate Of Return On Equity [Member] | Deferred For The Benefit Of Customers [Member]	'	'	'
Regulatory Matters [Line Items]	'	'	'
Earnings sharing mechanism allocation of earnings	50.00%	'	'
Above 10.5 Percent Rate Of Return On Equity [Member] | Shareholder Allocation [Member]	'	'	'
Regulatory Matters [Line Items]	'	'	'
Earnings sharing mechanism allocation of earnings	20.00%	'	'
Above 10.5 Percent Rate Of Return On Equity [Member] | Deferred For The Benefit Of Customers [Member]	'	'	'
Regulatory Matters [Line Items]	'	'	'
Earnings sharing mechanism allocation of earnings	80.00%	'	'