National Fuel Gas (NFG) 10-Q 2 Aug 19 2019 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - $ / shares	9 Months Ended
	Jun. 30, 2019	Jul. 31, 2019
Cover page.
Amendment Flag	false
City Area Code	716
Current Fiscal Year End Date	--09-30
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2019
Document Period End Date	Jun. 30, 2019
Document Quarterly Report	true
Document Transition Report	false
Document Type	10-Q
Entity Address, Address Line One	6363 Main Street
Entity Address, City or Town	Williamsville,
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	14221
Entity Central Index Key	0000070145
Entity Common Stock, Shares Outstanding		86,314,863
Entity Current Reporting Status	Yes
Entity Emerging Growth Company	false
Entity File Number	1-3880
Entity Filer Category	Large Accelerated Filer
Entity Incorporation, State or Country Code	NJ
Entity Interactive Data Current	Yes
Entity Registrant Name	NATIONAL FUEL GAS COMPANY
Entity Shell Company	false
Entity Small Business	false
Entity Tax Identification Number	13-1086010
Local Phone Number	857-7000
Title of 12(b) Security	Common Stock, par value $1.00 per share
Trading Symbol	NFG
Security Exchange Name	NYSE
Entity Listing, Par Value Per Share	$ 1

Consolidated Statements Of Inco

Consolidated Statements Of Income And Earnings Reinvested In The Business (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
INCOME
Operating Revenues	$ 357,200	$ 342,912	$ 1,399,991	$ 1,303,473
Operating Expenses:
Property, Franchise and Other Taxes	21,506	20,595	68,046	64,245
Depreciation, Depletion and Amortization	71,072	60,817	200,990	177,802
Total Operating Expenses	244,373	228,909	972,122	868,412
Operating Income	112,827	114,003	427,869	435,061
Other Income (Expense):
Other Income (Deductions)	(1,456)	(3,612)	(16,977)	(20,205)
Interest Expense on Long-Term Debt	(25,303)	(27,177)	(76,016)	(82,412)
Other Interest Expense	(1,202)	(1,006)	(4,061)	(2,742)
Income Before Income Taxes	84,866	82,208	330,815	329,702
Income Tax Expense (Benefit)	21,113	19,183	73,806	(23,825)
Net Income Available for Common Stock	63,753	63,025	257,009	353,527
EARNINGS REINVESTED IN THE BUSINESS
Balance at Beginning of Period	1,236,657	1,070,939	1,098,900	851,669
Beginning Retained Earnings Unappropriated And Current Period Net Income	1,300,410	1,133,964	1,355,909	1,205,196
Dividends on Common Stock	(37,543)	(36,526)	(110,885)	(107,758)
Balance at June 30	$ 1,262,867	$ 1,097,438	$ 1,262,867	$ 1,097,438
Earnings Per Common Share, Basic:
Net Income Available for Common Stock (in dollars per share)	$ 0.74	$ 0.73	$ 2.98	$ 4.12
Earnings Per Common Share, Diluted:
Net Income Available for Common Stock (in dollars per share)	$ 0.73	$ 0.73	$ 2.96	$ 4.09
Weighted Average Common Shares Outstanding:
Used in Basic Calculation (shares)	86,306,434	85,930,289	86,208,766	85,789,279
Used in Diluted Calculation (shares)	86,839,841	86,501,194	86,765,781	86,370,900
Dividends Per Common Share:
Dividends Declared (in dollars per share)	$ 0.435	$ 0.425	$ 1.285	$ 1.255
Purchased Gas [Member]
Operating Expenses:
Purchased Gas	$ 47,839	$ 52,211	$ 381,537	$ 322,854
Utility and Energy Marketing [Member]
INCOME
Operating Revenues	151,312	154,088	781,059	719,234
Operating Expenses:
Operation and Maintenance	39,607	39,560	132,082	130,348
Exploration and Production and Other [Member]
INCOME
Operating Revenues	159,864	137,492	470,267	425,811
Operating Expenses:
Operation and Maintenance	35,674	30,682	108,610	104,891
Pipeline and Storage and Gathering [Member]
INCOME
Operating Revenues	46,024	51,332	148,665	158,428
Operating Expenses:
Operation and Maintenance	28,675	25,044	80,857	68,272
Guidance for Recognition and Measurement of Financial Assets and Liabilities [Member]
EARNINGS REINVESTED IN THE BUSINESS
Cumulative Effect of Adoption of Authoritative Guidance	0	0	7,437	0
Guidance for Reclassification of Stranded Tax Effects [Member]
EARNINGS REINVESTED IN THE BUSINESS
Cumulative Effect of Adoption of Authoritative Guidance	$ 0	$ 0	$ 10,406	$ 0

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income Available for Common Stock	$ 63,753	$ 63,025	$ 257,009	$ 353,527
Other Comprehensive Income (Loss), Before Tax:
Unrealized Gain (Loss) on Securities Available for Sale Arising During the Period	0	(121)	0	(843)
Unrealized Gain (Loss) on Derivative Financial Instruments Arising During the Period	34,211	(37,452)	53,619	(55,534)
Reclassification Adjustment for Realized (Gains) Losses on Securities Available for Sale in Net Income	0	0	0	(430)
Reclassification Adjustment for Realized (Gains) Losses on Derivative Financial Instruments in Net Income	(3,869)	3,771	20,498	(5,577)
Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities to Earnings Reinvested in the Business	0	0	(11,738)	0
Other Comprehensive Income (Loss), Before Tax	30,342	(33,802)	62,379	(62,384)
Income Tax Expense (Benefit) Related to Unrealized Gain (Loss) on Securities Available for Sale Arising During the Period	0	42	0	(275)
Income Tax Expense (Benefit) Related to Unrealized Gain (Loss) on Derivative Financial Instruments Arising During the Period	9,835	(10,416)	15,434	(16,240)
Reclassification Adjustment for Income Tax Benefit (Expense) on Realized Losses (Gains) from Securities Available for Sale in Net Income	0	0	0	(158)
Reclassification Adjustment for Income Tax Benefit (Expense) on Realized Losses (Gains) from Derivative Financial Instruments in Net Income	(1,113)	1,208	5,756	(3,438)
Reclassification Adjustment for Income Tax Benefit (Expense) on the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities to Earnings Reinvested in the Business	0	0	(4,301)	0
Reclassification Adjustment for Stranded Tax Effects Related to the 2017 Tax Reform Act to Earnings Reinvested in the Business	0	0	10,406	0
Income Taxes – Net	8,722	(9,166)	27,295	(20,111)
Other Comprehensive Income (Loss)	21,620	(24,636)	35,084	(42,273)
Comprehensive Income	$ 85,373	$ 38,389	$ 292,093	$ 311,254

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands		Jun. 30, 2019	Sep. 30, 2018
ASSETS
Property, Plant and Equipment		$ 10,988,435	$ 10,439,839
Less - Accumulated Depreciation, Depletion and Amortization		5,636,065	5,462,696
Property, Plant and Equipment, Net, Total		5,352,370	4,977,143
Current Assets
Cash and Temporary Cash Investments		87,515	229,606
Hedging Collateral Deposits	[1]	6,835	3,441
Receivables – Net of Allowance for Uncollectible Accounts of $29,137 and $24,537, Respectively		178,762	141,498
Unbilled Revenue		18,047	24,182
Gas Stored Underground		17,075	37,813
Materials and Supplies - at average cost		39,010	35,823
Unrecovered Purchased Gas Costs		0	4,204
Other Current Assets		56,052	68,024
Total Current Assets		403,296	544,591
Other Assets
Recoverable Future Taxes		113,619	115,460
Unamortized Debt Expense		14,432	15,975
Other Regulatory Assets		107,206	112,918
Deferred Charges		33,627	40,025
Other Investments		137,847	132,545
Goodwill		5,476	5,476
Prepaid Post-Retirement Benefit Costs		88,939	82,733
Fair Value of Derivative Financial Instruments		36,803	9,518
Other		42,632	102
Total Other Assets		580,581	514,752
Total Assets		6,336,247	6,036,486
Capitalization:
Common Stock, $1 Par Value Authorized - 200,000,000 Shares; Issued and Outstanding - 86,306,593 Shares and 85,956,814 Shares, Respectively		86,307	85,957
Paid in Capital		827,243	820,223
Earnings Reinvested in the Business		1,262,867	1,098,900
Accumulated Other Comprehensive Loss		(32,666)	(67,750)
Total Comprehensive Shareholders’ Equity		2,143,751	1,937,330
Long-Term Debt, Net of Current Portion and Unamortized Discount and Debt Issuance Costs		2,133,101	2,131,365
Total Capitalization		4,276,852	4,068,695
Current and Accrued Liabilities
Notes Payable to Banks and Commercial Paper		0	0
Current Portion of Long-Term Debt		0	0
Accounts Payable		112,782	160,031
Amounts Payable to Customers		14,546	3,394
Dividends Payable		37,543	36,532
Interest Payable on Long-Term Debt		29,461	19,062
Customer Advances		166	13,609
Customer Security Deposits		16,801	25,703
Other Accruals and Current Liabilities		180,063	132,693
Fair Value of Derivative Financial Instruments		4,563	49,036
Total Current and Accrued Liabilities		395,925	440,060
Deferred Credits
Deferred Income Taxes		647,602	512,686
Taxes Refundable to Customers		366,184	370,628
Cost of Removal Regulatory Liability		218,340	212,311
Other Regulatory Liabilities		159,259	146,743
Pension and Other Post-Retirement Liabilities		53,142	66,103
Asset Retirement Obligations		104,732	108,235
Other Deferred Credits		114,211	111,025
Total Deferred Credits		1,663,470	1,527,731
Commitments and Contingencies (Note 7)		0	0
Total Capitalization and Liabilities		$ 6,336,247	$ 6,036,486
[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 ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Statement of Financial Position [Abstract]
Receivables, Allowance for Uncollectible Accounts	$ 29,137	$ 24,537
Common Stock, Par Value	$ 1	$ 1
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares Issued	86,306,593	85,956,814
Common Stock, Shares Outstanding	86,306,593	85,956,814

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
OPERATING ACTIVITIES
Net Income Available for Common Stock	$ 257,009	$ 353,527
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Depreciation, Depletion and Amortization	200,990	177,802
Deferred Income Taxes	111,123	(43,537)
Stock-Based Compensation	16,144	11,770
Other	7,964	12,311
Change in:
Receivables and Unbilled Revenue	(31,584)	(35,021)
Gas Stored Underground and Materials and Supplies	17,551	18,832
Unrecovered Purchased Gas Costs	4,204	4,623
Other Current Assets	11,972	(1,185)
Accounts Payable	(16,132)	2,327
Amounts Payable to Customers	11,152	16,833
Customer Advances	(13,443)	(15,504)
Customer Security Deposits	(8,902)	(1,904)
Other Accruals and Current Liabilities	36,040	26,538
Other Assets	(34,594)	(10,770)
Other Liabilities	1,061	1,441
Net Cash Provided by Operating Activities	570,555	518,083
INVESTING ACTIVITIES
Capital Expenditures	(587,442)	(403,994)
Net Proceeds from Sale of Oil and Gas Producing Properties	0	55,506
Other	(3,071)	(1,759)
Net Cash Used in Investing Activities	(590,513)	(350,247)
Financing Activities
Reduction of Long-Term Debt	0	(307,047)
Dividends Paid on Common Stock	(109,875)	(106,732)
Net Repurchases of Common Stock	(8,864)
Net Proceeds from Issuance of Common Stock		4,262
Net Cash Used in Financing Activities	(118,739)	(409,517)
Net Decrease in Cash, Cash Equivalents, and Restricted Cash	(138,697)	(241,681)
Cash, Cash Equivalents and Restricted Cash at October 1	233,047	557,271
Cash, Cash Equivalents and Restricted Cash at June 30	94,350	315,590
Supplemental Disclosure of Cash Flow Information, Non-Cash Investing Activities:
Non-Cash Capital Expenditures	$ 79,425	$ 71,410

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	9 Months Ended
	Jun. 30, 2019
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 Company uses proportionate consolidation when accounting for drilling arrangements related to oil and gas producing properties accounted for under the full cost method of accounting. 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 . In November 2016, the FASB issued authoritative guidance related to the presentation of restricted cash on the statement of cash flows. The new guidance requires restricted cash and cash equivalents be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows, and requires disclosure of how cash and cash equivalents on the statement of cash flows reconciles to the balance sheet. The Company considers Hedging Collateral Deposits to be restricted cash. The Company adopted this guidance effective October 1, 2018 on a retrospective basis. As a result, prior periods have been reclassified to conform to the current year presentation. Additional discussion is provided below at Consolidated Statement of Cash Flows. In March 2017, the FASB issued authoritative guidance related to the presentation of net periodic pension cost and net periodic postretirement benefit cost. The new guidance requires segregation of the service cost component from the other components of net periodic pension cost and net periodic postretirement benefit cost for financial reporting purposes. The service cost component is to be presented on the income statement in the same line items as other compensation costs included within Operating Expenses and the other components of net periodic pension cost and net periodic postretirement benefit cost are to be presented on the income statement below the subtotal labeled Operating Income (Loss). Under this guidance, the service cost component is eligible to be capitalized as part of the cost of inventory or property, plant and equipment while the other components of net periodic pension cost and net periodic postretirement benefit cost are generally not eligible for capitalization, unless allowed by a regulator. The Company adopted this guidance effective October 1, 2018. The Company applied the guidance retrospectively for the pension and postretirement benefit costs using amounts disclosed in prior period financial statement notes as estimates for the reclassifications in accordance with a practical expedient allowed under the guidance. For the quarter and nine months ended June 30, 2018, Operating Income increased $6.2 million and $28.6 million , respectively, and Other Income (Deductions) decreased by the same amounts as a result of the reclassifications. For the quarter and nine months ended June 30, 2019, Other Income (Deductions) includes $5.7 million and $25.5 million , respectively, of pension and postretirement benefit costs. 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, 2018 , 2017 and 2016 that are included in the Company's 2018 Form 10-K. The consolidated financial statements for the year ended September 30, 2019 will be audited by the Company's independent registered public accounting firm after the end of the fiscal year. The earnings for the nine months ended June 30, 2019 should not be taken as a prediction of earnings for the entire fiscal year ending September 30, 2019 . 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 8 – Business Segment Information. Consolidated Statements of Cash Flows. The components, as reported on the Company’s Consolidated Balance Sheets, of the total cash, cash equivalents, and restricted cash presented on the Statement of Cash Flows are as follows (in thousands): Nine Months Ended Nine Months Ended Balance at October 1, 2018 Balance at June 30, 2019 Balance at October 1, 2017 Balance at June 30, 2018 Cash and Temporary Cash Investments $ 229,606 $ 87,515 $ 555,530 $ 313,307 Hedging Collateral Deposits 3,441 6,835 1,741 2,283 Cash, Cash Equivalents, and Restricted Cash $ 233,047 $ 94,350 $ 557,271 $ 315,590 The Company considers all highly liquid debt instruments purchased with a maturity date of generally three months or less to be cash equivalents. The Company’s restricted cash is composed entirely of amounts reported as Hedging Collateral Deposits on the Consolidated Balance Sheets. Hedging Collateral Deposits is an account title for cash held in margin accounts funded by the Company to serve as collateral for hedging positions. 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. In the Utility segment, gas stored underground is carried at lower of cost or net realizable value, on a LIFO method. Gas stored underground 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 $16.3 million at June 30, 2019 , 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 $82.0 million and $62.2 million at June 30, 2019 and September 30, 2018 , 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 June 30, 2019, the ceiling exceeded the book value of the oil and gas properties by approximately $566.8 million . In adjusting estimated future cash flows for hedging under the ceiling test at June 30, 2019 , estimated future net cash flows were decreased by $23.9 million . Accumulated Other Comprehensive Loss. The components of Accumulated Other Comprehensive Loss and changes for the nine months ended June 30, 2019 and 2018, net of related tax effect, are as follows (amounts in parentheses indicate debits) (in thousands): 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 Three Months Ended June 30, 2019 Balance at April 1, 2019 $ 4,562 $ — $ (58,848 ) $ (54,286 ) Other Comprehensive Gains and Losses Before Reclassifications 24,376 — — 24,376 Amounts Reclassified From Other Comprehensive Income (Loss) (2,756 ) — — (2,756 ) Balance at June 30, 2019 $ 26,182 $ — $ (58,848 ) $ (32,666 ) Nine Months Ended June 30, 2019 Balance at October 1, 2018 $ (28,611 ) $ 7,437 $ (46,576 ) $ (67,750 ) Other Comprehensive Gains and Losses Before Reclassifications 38,185 — — 38,185 Amounts Reclassified From Other Comprehensive Income (Loss) 14,742 — — 14,742 Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities — (7,437 ) — (7,437 ) Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act 1,866 — (12,272 ) (10,406 ) Balance at June 30, 2019 $ 26,182 $ — $ (58,848 ) $ (32,666 ) Three Months Ended June 30, 2018 Balance at April 1, 2018 $ 3,841 $ 6,885 $ (58,486 ) $ (47,760 ) Other Comprehensive Gains and Losses Before Reclassifications (27,036 ) (163 ) — (27,199 ) Amounts Reclassified From Other Comprehensive Income (Loss) 2,563 — — 2,563 Balance at June 30, 2018 $ (20,632 ) $ 6,722 $ (58,486 ) $ (72,396 ) Nine Months Ended June 30, 2018 Balance at October 1, 2017 $ 20,801 $ 7,562 $ (58,486 ) $ (30,123 ) Other Comprehensive Gains and Losses Before Reclassifications (39,294 ) (568 ) — (39,862 ) Amounts Reclassified From Other Comprehensive Income (Loss) (2,139 ) (272 ) — (2,411 ) Balance at June 30, 2018 $ (20,632 ) $ 6,722 $ (58,486 ) $ (72,396 ) In February 2018, the FASB issued authoritative guidance that allows an entity to elect a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the 2017 Tax Reform Act and requires certain disclosures about stranded tax effects. The Company adopted this authoritative guidance effective January 1, 2019 and recorded a cumulative effect adjustment related to deferred income taxes associated with hedging activities and pension and post-retirement benefit obligations during the quarter ended March 31, 2019 to increase retained earnings by $10.4 million and decrease accumulated other comprehensive income by the same amount. In January 2016, the FASB issued authoritative guidance regarding the recognition and measurement of financial assets and liabilities. The authoritative guidance primarily affects the accounting for equity investments and the presentation and disclosure requirements for financial instruments. All equity investments in unconsolidated entities will be measured at fair value through earnings rather than through accumulated other comprehensive income. The Company adopted this authoritative guidance effective October 1, 2018 and, as called for by the modified retrospective method of adoption, recorded a cumulative effect adjustment during the quarter ended December 31, 2018 to increase retained earnings by $7.4 million and decrease accumulated other comprehensive income by the same amount. Reclassifications Out of Accumulated Other Comprehensive Loss. The details about the reclassification adjustments out of accumulated other comprehensive loss for the nine months ended June 30, 2019 and 2018 are as follows (amounts in parentheses indicate debits to the income statement) (in thousands): 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 Three Months Ended June 30, Nine Months Ended June 30, 2019 2018 2019 2018 Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges: Commodity Contracts $4,091 ($3,249 ) ($18,692 ) $6,125 Operating Revenues Commodity Contracts — 5 (1,182 ) 952 Purchased Gas Foreign Currency Contracts (222 ) (527 ) (624 ) (1,500 ) Operating Revenues Gains (Losses) on Securities Available for Sale — — — 430 Other Income (Deductions) 3,869 (3,771 ) (20,498 ) 6,007 Total Before Income Tax (1,113 ) 1,208 5,756 (3,596 ) Income Tax Expense $2,756 ($2,563 ) ($14,742 ) $2,411 Net of Tax Other Current Assets . The components of the Company’s Other Current Assets are as follows (in thousands): At June 30, 2019 At September 30, 2018 Prepayments $ 13,777 $ 10,770 Prepaid Property and Other Taxes 11,501 14,444 Federal Income Taxes Receivable 6,554 22,457 State Income Taxes Receivable 8,773 8,822 Fair Values of Firm Commitments 5,618 1,739 Regulatory Assets 9,829 9,792 $ 56,052 $ 68,024 Other Assets . The components of the Company’s Other Assets are as follows (in thousands): At June 30, 2019 At September 30, 2018 Federal Income Taxes Receivable $ 42,546 $ — Other 86 102 $ 42,632 $ 102 Other Accruals and Current Liabilities . The components of the Company’s Other Accruals and Current Liabilities are as follows (in thousands): At June 30, 2019 At September 30, 2018 Accrued Capital Expenditures $ 60,082 $ 38,354 Regulatory Liabilities 50,233 57,425 Reserve for Gas Replacement 16,251 — Liability for Royalty and Working Interests 19,846 12,062 Other 33,651 24,852 $ 180,063 $ 132,693 Earnings Per Common Share. Basic earnings per common share is computed by dividing income or loss 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 had outstanding were SARs, restricted stock units and performance shares. For the quarter and nine months ended June 30, 2019, 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. SARs, restricted stock units and performance shares that are antidilutive are excluded from the calculation of diluted earnings per common share. There were 120,546 securities and 122,327 securities excluded as being antidilutive for the quarter and nine months ended June 30, 2019, respectively. There were 1,095,838 securities and 316,279 securities excluded as being antidilutive for the quarter and nine months ended June 30, 2018, respectively. Stock-Based Compensation. The Company granted 244,734 performance shares during the nine months ended June 30, 2019 . The weighted average fair value of such performance shares was $55.67 per share for the nine months ended June 30, 2019 . 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 nine months ended June 30, 2019 must meet a performance goal related to relative return on capital over a three-year performance cycle. 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 nine months ended June 30, 2019 must meet a performance goal related to relative total shareholder return over a three-year performance cycle. 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 total 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 total shareholder return performance shares ("TSR 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 the TSR 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 TSR performance shares awarded, the result of which is recorded as compensation expense over the vesting term of the award. The Company granted 112,608 nonperformance-based restricted stock units during the nine months ended June 30, 2019 . The weighted average fair value of such nonperformance-based restricted stock units was $49.70 per share for the nine months ended June 30, 2019 . 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 nonperformance-based restricted stock units do not entitle the participant to receive dividends during the vesting period. The accounting for nonperformance-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. New Authoritative Accounting and Financial Reporting Guidance. In February 2016, the FASB issued authoritative guidance, which has subsequently been amended, requiring organizations that lease assets to recognize on the balance sheet the assets and liabilities for the rights and obligations created by all leases, regardless of whether they are considered to be capital leases or operating leases. The FASB’s previous authoritative guidance required organizations that lease assets to recognize on the balance sheet the assets and liabilities for the rights and obligations created by capital leases while excluding operating leases from balance sheet recognition. The new authoritative guidance will be effective as of the Company’s first quarter of fiscal 2020, with early adoption permitted. The Company does not anticipate early adoption. The Company will adopt the new authoritative guidance using the optional transition method, which permits an entity to initially apply the new lease accounting standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. The Company plans to apply practical expedients provided in the authoritative guidance that allow, among other things, an entity not to reassess contracts that commenced prior to the adoption date and to exclude all land easement arrangements that exist prior to the adoption date from treatment under the guidance. The Company also expects to elect a policy not to recognize right of use assets and lease liabilities related to short-term leases. The Company has finalized a plan for the adoption and implementation of the authoritative guidance and performed an initial assessment of its existing leasing arrangements and other contractual obligations. The Company also continues to evaluate and document technical accounting issues, policy considerations, financial reporting and disclosure implications, and changes to internal controls and businesses processes. While the Company continues to assess the impact on its financial statements, the Company expects that adoption of the authoritative guidance will result in an increase to its assets and liabilities on its consolidated balance sheet. In August 2017, the FASB issued authoritative guidance which changes the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities and to simplify the application of hedge accounting. The new guidance will be effective as of the Company’s first quarter of fiscal 2020, with early adoption permitted. The Company does not expect adoption of this guidance to have a significant impact on its consolidated financial statements and is currently evaluating the impact of this guidance.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	9 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers The Company adopted authoritative guidance regarding revenue recognition on October 1, 2018 using the modified retrospective method of adoption for open contracts as of October 1, 2018. A cumulative effect adjustment to retained earnings was not necessary since no revenue recognition differences were identified when comparing the revenue recognition criteria under the new authoritative guidance to the previous guidance. The Company records revenue related to its derivative financial instruments in the Exploration and Production segment as well as in the Energy Marketing segment. The Company also records revenue related to alternative revenue programs in its Utility segment. Revenue related to derivative financial instruments and alternative revenue programs are excluded from the scope of the new authoritative guidance since they are accounted for under other existing accounting guidance. The following tables provide a disaggregation of the Company's revenues for the quarter and nine months ended June 30, 2019 , presented by type of service from each reportable segment. Quarter Ended June 30, 2019 (Thousands) Revenues By Type of Service Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing All Other Corporate and Intersegment Eliminations Total Consolidated Production of Natural Gas $ 113,975 $ — $ — $ — $ — $ — $ — $ 113,975 Production of Crude Oil 38,823 — — — — — — 38,823 Natural Gas Processing 731 — — — — — — 731 Natural Gas Gathering Services — — 32,875 — — — (32,875 ) — Natural Gas Transportation Service — 50,001 — 23,010 — — (17,672 ) 55,339 Natural Gas Storage Service — 18,598 — — — — (8,060 ) 10,538 Natural Gas Residential Sales — — — 96,146 — — — 96,146 Natural Gas Commercial Sales — — — 12,107 — — — 12,107 Natural Gas Industrial Sales — — — 1,032 — — — 1,032 Natural Gas Marketing — — — — 22,212 — (681 ) 21,531 Other 152 368 — 161 5 854 (20 ) 1,520 Total Revenues from Contracts with Customers 153,681 68,967 32,875 132,456 22,217 854 (59,308 ) 351,742 Alternative Revenue Programs — — — 465 — — — 465 Derivative Financial Instruments 5,194 — — — (201 ) — — 4,993 Total Revenues $ 158,875 $ 68,967 $ 32,875 $ 132,921 $ 22,016 $ 854 $ (59,308 ) $ 357,200 Nine Months Ended June 30, 2019 (Thousands) Revenues By Type of Service Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing All Other Corporate and Intersegment Eliminations Total Consolidated Production of Natural Gas $ 371,710 $ — $ — $ — $ — $ — $ — $ 371,710 Production of Crude Oil 111,256 — — — — — — 111,256 Natural Gas Processing 2,676 — — — — — — 2,676 Natural Gas Gathering Services — — 91,931 — — — (91,931 ) — Natural Gas Transportation Service — 158,376 — 103,723 — — (54,556 ) 207,543 Natural Gas Storage Service — 56,887 — — — — (24,367 ) 32,520 Natural Gas Residential Sales — — — 492,267 — — — 492,267 Natural Gas Commercial Sales — — — 68,408 — — — 68,408 Natural Gas Industrial Sales — — — 4,400 — — — 4,400 Natural Gas Marketing — — — — 130,015 — (1,056 ) 128,959 Other 1,028 3,112 2 (8,662 ) 15 2,170 (529 ) (2,864 ) Total Revenues from Contracts with Customers 486,670 218,375 91,933 660,136 130,030 2,170 (172,439 ) 1,416,875 Alternative Revenue Programs — — — (1,528 ) — — — (1,528 ) Derivative Financial Instruments (18,817 ) — — — 3,461 — — (15,356 ) Total Revenues $ 467,853 $ 218,375 $ 91,933 $ 658,608 $ 133,491 $ 2,170 $ (172,439 ) $ 1,399,991 Exploration and Production Segment Revenue The Company’s Exploration and Production segment records revenue from the sale of the natural gas and oil that it produces and natural gas liquids (NGLs) processed based on entitlement, which means that revenue is recorded based on the actual amount of natural gas or oil that is delivered to a pipeline, or upon pick-up in the case of NGLs, and the Company’s ownership interest. Natural gas production occurs primarily in the Appalachian region of the United States and crude oil production occurs primarily in the West Coast region of the United States. If a production imbalance occurs between what was supposed to be delivered to a pipeline and what was actually produced and delivered, the Company accrues the difference as an imbalance. The sales contracts generally require the Company to deliver a specific quantity of a commodity per day for a specific number of days at a price that is either fixed or variable and considers the delivery of each unit (MMBtu or Bbl) to be a separate performance obligation that is satisfied upon delivery. The transaction price for the sale of natural gas, oil and NGLs is contractually agreed upon based on prevailing market pricing (primarily tied to a market index with certain adjustments based on factors such as delivery location and prevailing supply and demand conditions) or fixed pricing. The Company allocates the transaction price to each performance obligation on the basis of the relative standalone selling price of each distinct unit sold. Revenue is recognized at a point in time when the transfer of the commodity occurs at the delivery point per the contract. The amount billable, as determined by the contracted quantity and price, indicates the value to the customer, and is used for revenue recognition purposes by the Exploration and Production segment as specified by the “invoice practical expedient” (the amount that the Exploration and Production segment has the right to invoice) under the authoritative guidance for revenue recognition. The contracts typically require payment within 30 days of the end of the calendar month in which the natural gas and oil is delivered, or picked up in the case of NGLs. The Company uses derivative financial instruments to manage commodity price risk in the Exploration and Production segment related to sales of the natural gas and oil that it produces. Gains or losses on such derivative financial instruments are recorded as adjustments to revenue; however, they are not considered to be revenue from contracts with customers. Pipeline and Storage Segment Revenue The Company’s Pipeline and Storage segment records revenue for natural gas transportation and storage services in New York and Pennsylvania at tariff-based rates regulated by the FERC. Customers secure their own gas supply and the Pipeline and Storage segment provides transportation and/or storage services to move the customer-supplied gas to the intended location, including injections into or withdrawals from the storage field. This performance obligation is satisfied over time. The rate design for the Pipeline and Storage segment’s customers generally includes a combination of volumetric or commodity charges as well as monthly “fixed” charges (including charges commonly referred to as capacity charges, demand charges, or reservation charges). These types of fixed charges represent compensation for standing ready over the period of the month to deliver quantities of gas, regardless of whether the customer takes delivery of any quantity of gas. The performance obligation under these circumstances is satisfied based on the passage of time and meter reads, if applicable, which correlates to the period for which the charges are eligible to be invoiced. The amount billable, as determined by the meter read and the “fixed” monthly charge, indicates the value to the customer, and is used for revenue recognition purposes by the Pipeline and Storage segment as specified by the “invoice practical expedient” (the amount that the Pipeline and Storage segment has the right to invoice) under the authoritative guidance for revenue recognition. Customers are billed after the end of each calendar month, with payment typically due by the 25th day of the month in which the invoice is received. The Company’s Pipeline and Storage segment expects to recognize the following revenue amounts in future periods related to “fixed” charges associated with remaining performance obligations for transportation and storage contracts: $41.8 million for the remainder of fiscal 2019; $158.9 million for fiscal 2020; $135.3 million for fiscal 2021; $114.1 million for fiscal 2022; $82.3 million for fiscal 2023; and $370.5 million thereafter. Gathering Segment Revenue The Company’s Gathering segment provides gathering and processing services in the Appalachian region of Pennsylvania, primarily for Seneca. The Gathering segment’s primary performance obligation is to deliver gathered natural gas volumes from Seneca’s wells into interstate pipelines at contractually agreed upon per unit rates. This obligation is satisfied over time. The performance obligation is satisfied based on the passage of time and meter reads, which correlates to the period for which the charges are eligible to be invoiced. The amount billable, as determined by the meter read and the contracted volumetric rate, indicates the value to the customer, and is used for revenue recognition purposes by the Gathering segment as specified by the “invoice practical expedient” (the amount that the Gathering segment has the right to invoice) under the authoritative guidance for revenue recognition. Customers are billed after the end of each calendar month, with payment typically due by the 10th day after the invoice is received. Utility Segment Revenue The Company’s Utility segment records revenue for natural gas sales and natural gas transportation services in western New York and northwestern Pennsylvania at tariff-based rates regulated by the NYPSC and the PaPUC. Natural gas sales and transportation services are provided largely to residential, commercial and industrial customers. The Utility segment’s performance obligation to its customers is to deliver natural gas, an obligation which is satisfied over time. This obligation generally remains in effect as long as the customer consumes the natural gas provided by the Utility segment. The Utility segment recognizes revenue when it satisfies its performance obligation by delivering natural gas to the customer. Natural gas is delivered and consumed by the customer simultaneously. The satisfaction of the performance obligation is measured by the turn of the meter dial. The amount billable, as determined by the meter read and the tariff-based rate, indicates the value to the customer, and is used for revenue recognition purposes by the Utility segment as specified by the “invoice practical expedient” (the amount that the Utility segment has the right to invoice) under the authoritative guidance for revenue recognition. Since the Utility segment bills its customers in cycles having billing dates that do not generally coincide with the end of a calendar month, a receivable is recorded for natural gas delivered but not yet billed to customers based on an estimate of the amount of natural gas delivered between the last meter reading date and the end of the accounting period. Such receivables are a component of Unbilled Revenue on the Consolidated Balance Sheets. The Utility segment’s tariffs allow customers to utilize budget billing. In this situation, since the amount billed may differ from the amount of natural gas delivered to the customer in any given month, revenue is recognized monthly based on the amount of natural gas consumed. The differential between the amount billed and the amount consumed is recorded as a component of Receivables or Customer Advances on the Consolidated Balance Sheets. All receivables or advances related to budget billing are settled within one year. Utility Segment Alternative Revenue Programs As indicated in the revenue table shown above, the Company’s Utility segment has alternative revenue programs that are excluded from the scope of the new authoritative guidance regarding revenue recognition. The NYPSC has authorized alternative revenue programs that are designed to mitigate the impact that weather and conservation have on margin. The NYPSC has also authorized additional alternative revenue programs that adjust billings for the effects of broad external factors or to compensate the Company for demand-side management initiatives. These alternative revenue programs primarily allow the Company and customer to share in variances from imputed margins due to migration of transportation customers, allow for adjustments to the gas cost recovery mechanism for fluctuations in uncollectible expenses associated with gas costs, and allow the Company to pass on to customers costs associated with customer energy efficiency programs. In general, revenue is adjusted monthly for these programs and is collected from or passed back to customers within 24 months of the annual reconciliation period. Energy Marketing Segment Revenue The Company’s Energy Marketing segment records revenue for competitively priced natural gas sales in western and central New York and northwestern Pennsylvania. Sales are provided largely to industrial, wholesale, commercial, public authority and residential customers. The Energy Marketing segment’s performance obligation to its customers is to deliver natural gas, an obligation which is satisfied over time. This obligation generally remains in effect as long as the customer consumes the natural gas provided by the Energy Marketing segment. The Energy Marketing segment recognizes revenue when it satisfies its performance obligation by delivering natural gas to the customer. Natural gas is delivered and consumed by the customer simultaneously. The satisfaction of the performance obligation is measured by the turn of the meter dial. The amount billable, as determined by the meter read and the contracted or market based rate, indicates the value to the customer, and is used for revenue recognition purposes by the Energy Marketing segment as specified by the “invoice practical expedient” (the amount that the Energy Marketing segment has the right to invoice) under the authoritative guidance for revenue recognition. Since the Energy Marketing segment bills its residential customers in cycles having billing dates that do not generally coincide with the end of a calendar month, a receivable is recorded for natural gas delivered but not yet billed to customers based on an estimate of the amount of natural gas delivered between the last meter reading date and the end of the accounting period. Such receivables are a component of Unbilled Revenue on the Consolidated Balance Sheets. The Energy Marketing segment also allows customers to utilize budget billing. In this situation, since the amount billed may differ from the amount of natural gas delivered to the customer in any given month, revenue is recognized monthly based on the amount of natural gas consumed. The differential between the amount billed and the amount consumed is recorded as a component of Receivables or Customer Advances on the Consolidated Balance Sheets. All receivables or advances related to budget billing are settled within one year. The Company uses derivative financial instruments to manage commodity price risk in the Energy Marketing segment related to the sale of natural gas to its customers. Gains or losses on such derivative financial instruments are recorded as adjustments to revenue; however, they are not considered to be revenue from contracts with customers.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Jun. 30, 2019
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 June 30, 2019 and September 30, 2018 . 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 combines gas and oil swaps 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 June 30, 2019 (Thousands of Dollars) Level 1 Level 2 Level 3 Netting Adjustments (1) Total (1) Assets: Cash Equivalents – Money Market Mutual Funds $ 75,375 $ — $ — $ — $ 75,375 Derivative Financial Instruments: Commodity Futures Contracts – Gas 1,367 — — (1,367 ) — Over the Counter Swaps – Gas and Oil — 44,929 — (6,850 ) 38,079 Foreign Currency Contracts — 78 — (1,500 ) (1,422 ) Other Investments: Balanced Equity Mutual Fund 40,313 — — — 40,313 Fixed Income Mutual Fund 55,034 — — — 55,034 Common Stock – Financial Services Industry 1,841 — — — 1,841 Hedging Collateral Deposits 6,835 — — — 6,835 Total $ 180,765 $ 45,007 $ — $ (9,717 ) $ 216,055 Liabilities: Derivative Financial Instruments: Commodity Futures Contracts – Gas $ 5,686 $ — $ — $ (1,367 ) $ 4,319 Over the Counter Swaps – Gas and Oil — 7,071 — (6,850 ) 221 Foreign Currency Contracts — 1,523 — (1,500 ) 23 Total $ 5,686 $ 8,594 $ — $ (9,717 ) $ 4,563 Total Net Assets/(Liabilities) $ 175,079 $ 36,413 $ — $ — $ 211,492 Recurring Fair Value Measures At fair value as of September 30, 2018 (Thousands of Dollars) Level 1 Level 2 Level 3 Netting Adjustments (1) Total (1) Assets: Cash Equivalents – Money Market Mutual Funds $ 215,272 $ — $ — $ — $ 215,272 Derivative Financial Instruments: Commodity Futures Contracts – Gas 1,075 — — (1,075 ) — Over the Counter Swaps – Gas and Oil — 26,074 — (17,041 ) 9,033 Foreign Currency Contracts — 443 — (443 ) — Other Investments: Balanced Equity Mutual Fund 38,468 — — — 38,468 Fixed Income Mutual Fund 51,331 — — — 51,331 Common Stock – Financial Services Industry 2,776 — — — 2,776 Hedging Collateral Deposits 3,441 — — — 3,441 Total $ 312,363 $ 26,517 $ — $ (18,559 ) $ 320,321 Liabilities: Derivative Financial Instruments: Commodity Futures Contracts – Gas $ 2,412 $ — $ — $ (1,075 ) $ 1,337 Over the Counter Swaps – Gas and Oil — 64,224 — (17,041 ) 47,183 Foreign Currency Contracts — 959 — (443 ) 516 Total $ 2,412 $ 65,183 $ — $ (18,559 ) $ 49,036 Total Net Assets/(Liabilities) $ 309,951 $ (38,666 ) $ — $ — $ 271,285 (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 June 30, 2019 and September 30, 2018 , 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 were $6.8 million at June 30, 2019 and $3.4 million at September 30, 2018, which were associated with these futures contracts and have been reported in Level 1 as well. The derivative financial instruments reported in Level 2 at June 30, 2019 and September 30, 2018 consist of natural gas price swap agreements used in the Company’s Exploration and Production and Energy Marketing segments, crude oil price swap agreements used in the Company’s Exploration and Production segment, basis hedge swap agreements used in the Company's Energy Marketing segment and foreign currency contracts 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 fair value of the Level 2 foreign currency contracts is determined using the market approach based on observable market transactions of forward Canadian currency rates. 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 June 30, 2019 , 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's (assuming the derivative is in a gain position) or the Company’s (assuming the derivative is in a loss position) credit default swaps rates. For the quarters ended June 30, 2019 and June 30, 2018 , there were no assets or liabilities measured at fair value and classified as Level 3. For the quarters ended June 30, 2019 and June 30, 2018 , no

Financial Instruments

Financial Instruments	9 Months Ended
	Jun. 30, 2019
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): June 30, 2019 September 30, 2018 Carrying Amount Fair Value Carrying Amount Fair Value Long-Term Debt $ 2,133,101 $ 2,252,231 $ 2,131,365 $ 2,121,861 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. The components of the Company's Other Investments are as follows (in thousands): At June 30, 2019 At September 30, 2018 Life Insurance Contracts $ 40,659 $ 39,970 Equity Mutual Fund 40,313 38,468 Fixed Income Mutual Fund 55,034 51,331 Marketable Equity Securities 1,841 2,776 $ 137,847 $ 132,545 Investments in life insurance contracts are stated at their cash surrender values or net present value. Investments in an equity mutual fund, a fixed income mutual fund and the stock of an insurance company (marketable equity securities) are stated at fair value based on quoted market prices with changes in fair value recognized in net income. The insurance contracts and marketable equity and fixed income securities are primarily informal funding mechanisms for various benefit obligations the Company has to certain employees. Derivative Financial Instruments. The Company uses derivative financial instruments to manage commodity price risk in the Exploration and Production segment as well as the Energy Marketing segment. 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. In addition, the Company also enters into foreign exchange forward contracts to manage the risk of currency fluctuations associated with transportation costs denominated in Canadian currency in the Exploration and Production segment. These instruments are accounted for as cash flow hedges. The Company also enters into futures contracts and swaps, which are accounted for as cash flow hedges, to manage the price risk associated with forecasted gas purchases. The Company enters into futures contracts and swaps to mitigate risk associated with fixed price sales commitments, fixed price purchase commitments, and the decline in value of natural gas held in storage. These instruments are accounted for as fair value hedges. The duration of the Company’s combined cash flow and fair value commodity hedges does not typically exceed 5 years while the foreign currency forward contracts do not exceed 7 years . The Exploration and Production segment holds the majority of the Company’s derivative financial instruments. The Company has presented its net derivative assets and liabilities as “Fair Value of Derivative Financial Instruments” on its Consolidated Balance Sheets at June 30, 2019 and September 30, 2018 . Substantially all of the derivative financial instruments reported on those line items relate to commodity contracts and a small portion relates to foreign currency forward 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 June 30, 2019 , the Company had the following commodity derivative contracts (swaps and futures contracts) outstanding: Commodity Units Natural Gas 80.2 Bcf (short positions) Natural Gas 3.7 Bcf (long positions) Crude Oil 3,225,000 Bbls (short positions) As of June 30, 2019 , the Company was hedging a total of $79.7 million of forecasted transportation costs denominated in Canadian dollars with foreign currency forward contracts (long positions). As of June 30, 2019 , the Company had $36.7 million ( $26.2 million after tax) of net hedging gains included in the accumulated other comprehensive income (loss) balance. It is expected that $28.7 million ( $20.5 million after tax) of unrealized gains will be reclassified into the Consolidated Statement of Income within the next 12 months as the underlying hedged transactions are recorded in earnings. The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the Three Months Ended June 30, 2019 and 2018 (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 June 30, 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 June 30, 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 June 30, 2019 2018 2019 2018 2019 2018 Commodity Contracts $ 33,531 $ (35,976 ) Operating Revenue $ 4,091 $ (3,249 ) Operating Revenue $ 1,020 $ (339 ) Commodity Contracts 150 124 Purchased Gas — 5 Not Applicable — — Foreign Currency Contracts 530 (1,600 ) Operating Revenue (222 ) (527 ) Not Applicable — — Total $ 34,211 $ (37,452 ) $ 3,869 $ (3,771 ) $ 1,020 $ (339 ) The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the Nine Months Ended June 30, 2019 and 2018 (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 Nine Months Ended June 30, 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 Nine Months Ended June 30, 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 Nine Months Ended June 30, 2019 2018 2019 2018 2019 2018 Commodity Contracts $ 56,356 $ (52,440 ) Operating Revenue $ (18,692 ) $ 6,125 Operating Revenue $ 783 $ (436 ) Commodity Contracts (1,183 ) 737 Purchased Gas (1,182 ) 952 Not Applicable — — Foreign Currency Contracts (1,554 ) (3,831 ) Operating Revenue (624 ) (1,500 ) Not Applicable — — Total $ 53,619 $ (55,534 ) $ (20,498 ) $ 5,577 $ 783 $ (436 ) Fair Value Hedges The Company 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 net realizable value writedown of the value of natural gas in storage that is recorded in the Company’s financial statements. As of June 30, 2019 , the Company’s Energy Marketing segment had fair value hedges covering approximately 24.8 Bcf ( 24.3 Bcf of fixed price sales commitments and 0.5 Bcf of commitments related to the withdrawal of storage gas). 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 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 Nine Months Ended June 30, 2019 (In Thousands) Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income for the Nine Months Ended June 30, 2019 (In Thousands) Commodity Contracts Operating Revenues $ (3,507 ) $ 3,507 Commodity Contracts Purchased Gas $ 240 $ (240 ) $ (3,267 ) $ 3,267 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 and applicable foreign currency forward contracts with eighteen counterparties of which seventeen are in a net gain position. On average, the Company had $2.1 million of credit exposure per counterparty in a gain position at June 30, 2019 . The maximum credit exposure per counterparty in a gain position at June 30, 2019 was $6.1 million . As of June 30, 2019 , 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 June 30, 2019 , fifteen of the eighteen counterparties to the Company’s outstanding derivative instrument contracts (specifically the over-the-counter swaps and applicable foreign currency forward contracts) 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 liability were larger) and/or the Company’s credit rating declined, then additional hedging collateral deposits may be required. At June 30, 2019 , the fair market value of the derivative financial instrument assets with a credit-risk related contingency feature was $27.3 million according to the Company’s internal model (discussed in Note 3 — Fair Value Measurements). At June 30, 2019 , the fair market value of the derivative financial instrument liabilities with a credit-risk related contingency feature was $0.2 million according to the Company's internal model. For its over-the-counter swap agreements and foreign currency forward contracts, no hedging collateral deposits were required to be posted by the Company at June 30, 2019 . For its exchange traded futures contracts, the Company was required to post $6.8 million in hedging collateral deposits as of June 30, 2019 . As these are exchange traded futures contracts, there are no specific credit-risk related contingency features. The Company posts or receives hedging collateral based on open positions and margin requirements it has with its counterparties. The Company’s requirement to post hedging collateral deposits and the Company's right to receive 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.

Income Taxes

Income Taxes	9 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rates for the quarters ended June 30, 2019 and June 30, 2018 were 24.9% and 23.3% , respectively. The increase in the effective tax rates was primarily the result of a one-time tax benefit recorded as part of an IRS settlement in fiscal 2018. The effective tax rates for the nine months ended June 30, 2019 and June 30, 2018 were 22.3% and negative 7.2% , respectively. The difference is a result of the impact of the one-time remeasurement of the deferred income tax liability under the 2017 Tax Reform Act. On December 22, 2017, the 2017 Tax Reform Act was enacted. The 2017 Tax Reform Act included a reduction in the corporate federal income tax rate from 35% to a blended 24.5% for fiscal 2018 and 21% for fiscal 2019 and beyond. The Company’s accumulated deferred income taxes were remeasured based upon the new tax rates. For the non-rate regulated activities through the year ended September 30, 2018, the change in beginning of the year deferred income taxes of $103.5 million was recorded as a reduction to income tax expense. For the Company's rate regulated activities, the reduction in deferred income taxes of $336.7 million was recorded as a decrease to Recoverable Future Taxes of $65.7 million and an increase to Taxes Refundable to Customers of $271.0 million . The 2017 Tax Reform Act includes provisions that stipulate how these excess deferred taxes are to be passed back to customers for certain accelerated tax depreciation benefits. Potential refunds of other deferred income taxes will be determined by the federal and state regulatory agencies. For further discussion, refer to Note 10 — Regulatory Matters. The 2017 Tax Reform Act also provides that the Company’s existing alternative minimum tax (AMT) credit carryovers are refundable, if not utilized to reduce tax, beginning in fiscal 2019. During fiscal 2018, the Department of Treasury indicated that a portion of the refundable AMT credit carryovers would be subject to sequestration. Accordingly, the Company recorded a $5.0 million valuation allowance related to this sequestration. During the quarter ended December 31, 2018, the Office of Management and Budget determined that these AMT refunds would not be subject to sequestration. As such, the Company has removed the valuation allowance. In addition, the Company reclassified the estimated fiscal 2019 refund, approximately $42.5 million

Capitalization

Capitalization	9 Months Ended
	Jun. 30, 2019
Capitalization, Long-term Debt and Equity [Abstract]
Capitalization	Capitalization Summary of Changes in Common Stock Equity Common Stock Paid In Capital Earnings Reinvested in the Business Accumulated Other Comprehensive Income (Loss) Shares Amount (Thousands, except per share amounts) Balance at April 1, 2019 86,301 $ 86,301 $ 821,837 $ 1,236,657 $ (54,286 ) Net Income Available for Common Stock 63,753 Dividends Declared on Common Stock ($0.435 Per Share) (37,543 ) Other Comprehensive Income, Net of Tax 21,620 Share-Based Payment Expense (1) 5,054 Common Stock Issued Under Stock and Benefit Plans 6 6 352 Balance at June 30, 2019 86,307 $ 86,307 $ 827,243 $ 1,262,867 $ (32,666 ) Balance at October 1, 2018 85,957 $ 85,957 $ 820,223 $ 1,098,900 $ (67,750 ) Net Income Available for Common Stock 257,009 Dividends Declared on Common Stock ($1.285 Per Share) (110,885 ) Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities 7,437 Cumulative Effect of Adoption of Authoritative Guidance for Reclassification of Stranded Tax Effects 10,406 Other Comprehensive Income, Net of Tax 35,084 Share-Based Payment Expense (1) 15,008 Common Stock Issued (Repurchased) Under Stock and Benefit Plans 350 350 (7,988 ) Balance at June 30, 2019 86,307 $ 86,307 $ 827,243 $ 1,262,867 $ (32,666 ) Balance at April 1, 2018 85,882 $ 85,882 $ 810,126 $ 1,070,939 $ (47,760 ) Net Income Available for Common Stock 63,025 Dividends Declared on Common Stock ($0.425 Per Share) (36,526 ) Other Comprehensive Loss, Net of Tax (24,636 ) Share-Based Payment Expense (1) 3,558 Common Stock Issued Under Stock and Benefit Plans 62 62 2,711 Balance at June 30, 2018 85,944 $ 85,944 $ 816,395 $ 1,097,438 $ (72,396 ) Balance at October 1, 2017 85,543 $ 85,543 $ 796,646 $ 851,669 $ (30,123 ) Net Income Available for Common Stock 353,527 Dividends Declared on Common Stock ($1.255 Per Share) (107,758 ) Other Comprehensive Loss, Net of Tax (42,273 ) Share-Based Payment Expense (1) 10,632 Common Stock Issued Under Stock and Benefit Plans 401 401 9,117 Balance at June 30, 2018 85,944 $ 85,944 $ 816,395 $ 1,097,438 $ (72,396 ) (1) Paid in Capital includes compensation costs associated with performance shares and/or restricted stock awards. The expense is included within Net Income Available For Common Stock, net of tax benefits. Common Stock. During the nine months ended June 30, 2019 , the Company issued 126,879 original issue shares of common stock as a result of SARs exercises, 79,654 original issue shares of common stock for restricted stock units that vested and 281,882 original issue shares of common stock for performance shares that vested. The Company also issued 20,501 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 nine months ended June 30, 2019 . Holders of stock-based compensation awards will often tender shares of common stock to the Company for payment of applicable withholding taxes. During the nine months ended June 30, 2019 , 159,137 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 as of June 30, 2019

Commitments And Contingencies

Commitments And Contingencies	9 Months Ended
	Jun. 30, 2019
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 requirements. 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 June 30, 2019 , the Company has estimated its remaining clean-up costs related to former manufactured gas plant sites will be approximately $7.1 million , which includes a $3.9 million estimated minimum liability to remediate a former manufactured gas plant site located in New York. In March 2018, the NYDEC issued a Record of Decision for this New York site and the minimum liability reflects the remedy selected in the Record of Decision. The Company's liability for such clean-up costs has been recorded in Other Deferred Credits on the Consolidated Balance Sheet at June 30, 2019 . The Company expects to recover its environmental clean-up costs through rate recovery over a period of approximately 3 years and 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. Northern Access Project. On February 3, 2017, Supply Corporation and Empire received FERC approval of the Northern Access project described herein. On April 7, 2017, the NYDEC issued a Notice of Denial of the federal Clean Water Act Section 401 Water Quality Certification and other state stream and wetland permits for the New York portion of the project (the Water Quality Certification for the Pennsylvania portion of the project was received on January 27, 2017). On April 21, 2017, Supply Corporation and Empire filed a Petition for Review in the United States Court of Appeals for the Second Circuit of the NYDEC's Notice of Denial with respect to National Fuel's application for the Water Quality Certification, and on May 11, 2017, the Company commenced legal action in New York State Supreme Court challenging the NYDEC's actions with regard to various state permits. On August 6, 2018, the FERC issued an Order finding that the NYDEC exceeded the statutory time frame to take action under the Clean Water Act and, therefore, waived its opportunity to approve or deny the Water Quality Certification. FERC denied rehearing requests associated with its Order. In light of these legal actions and the need to complete necessary project development activities in advance of construction, the in-service date for the project is expected to be no earlier than fiscal 2022. 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	9 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Business Segment Information	Business Segment Information The Company reports financial results for five segments: Exploration and Production, Pipeline and Storage, Gathering, Utility and Energy Marketing. 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 2018 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 2018 Form 10-K. A listing of segment assets at June 30, 2019 and September 30, 2018 is shown in the tables below. Quarter Ended June 30, 2019 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $158,875 $46,024 $— $129,977 $21,335 $356,211 $854 $135 $357,200 Intersegment Revenues $— $22,943 $32,875 $2,944 $681 $59,443 $— $(59,443) $— Segment Profit: Net Income (Loss) $26,512 $15,792 $14,638 $7,362 $(1,441) $62,863 $(3) $893 $63,753 Nine Months Ended June 30, 2019 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $467,853 $148,663 $2 $648,624 $132,435 $1,397,577 $2,170 $244 $1,399,991 Intersegment Revenues $— $69,712 $91,931 $9,984 $1,056 $172,683 $— $(172,683) $— Segment Profit: Net Income (Loss) $86,599 $58,643 $41,511 $68,600 $(1,198) $254,155 $252 $2,602 $257,009 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Segment Assets: At June 30, 2019 $1,847,706 $1,894,824 $555,185 $1,967,123 $45,736 $6,310,574 $78,528 $(52,855) $6,336,247 At September 30, 2018 $1,568,563 $1,848,180 $533,608 $1,921,971 $50,971 $5,923,293 $78,109 $35,084 $6,036,486 Quarter Ended June 30, 2018 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $135,828 $51,363 $(31) $128,628 $25,460 $341,248 $1,496 $168 $342,912 Intersegment Revenues $— $22,496 $27,908 $3,519 $512 $54,435 $— $(54,435) $— Segment Profit: Net Income (Loss) $27,817 $20,723 $11,566 $3,930 $(190) $63,846 $297 $(1,118) $63,025 Nine Months Ended June 30, 2018 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $421,381 $158,387 $41 $599,495 $119,739 $1,299,043 $3,824 $606 $1,303,473 Intersegment Revenues $— $67,524 $79,404 $11,401 $589 $158,918 $— $(158,918) $— Segment Profit: Net Income (Loss) $161,052 $81,909 $68,736 $58,283 $1,434 $371,414 $(214) $(17,673) $353,527

Retirement Plan And Other Post-

Retirement Plan And Other Post-Retirement Benefits	9 Months Ended
	Jun. 30, 2019
Retirement Benefits [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 June 30, 2019 2018 2019 2018 Service Cost $ 2,120 $ 2,480 $ 380 $ 458 Interest Cost 9,594 8,252 4,286 3,700 Expected Return on Plan Assets (15,591 ) (15,429 ) (7,539 ) (7,871 ) Amortization of Prior Service Cost (Credit) 206 235 (107 ) (107 ) Amortization of Losses 8,024 9,301 1,490 2,639 Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1) (113 ) 712 3,757 3,386 Net Periodic Benefit Cost $ 4,240 $ 5,551 $ 2,267 $ 2,205 Retirement Plan Other Post-Retirement Benefits Nine Months Ended June 30, 2019 2018 2019 2018 Service Cost $ 6,362 $ 7,441 $ 1,140 $ 1,373 Interest Cost 28,783 24,754 12,858 11,101 Expected Return on Plan Assets (46,775 ) (46,286 ) (22,618 ) (23,612 ) Amortization of Prior Service Cost (Credit) 619 703 (321 ) (322 ) Amortization of Losses 24,072 27,904 4,471 7,918 Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1) 5,490 8,926 14,294 13,243 Net Periodic Benefit Cost $ 18,551 $ 23,442 $ 9,824 $ 9,701 (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 nine months ended June 30, 2019 , the Company contributed $29.2 million to its tax-qualified, noncontributory defined-benefit retirement plan (Retirement Plan) and $2.7 million to its VEBA trusts for its other post-retirement benefits. In the remainder of 2019 , the Company may contribute up to $5.0 million to the Retirement Plan and the Company expects to contribute approximately $0.2 million to its VEBA trusts.

Regulatory Matters

Regulatory Matters	9 Months Ended
	Jun. 30, 2019
Regulatory Assets and Liabilities, Other Disclosures [Abstract]
Regulatory Matters	Regulatory Matters New York Jurisdiction Distribution Corporation's current delivery rates in its New York jurisdiction were approved by the NYPSC in an order issued on April 20, 2017 with rates becoming effective May 1, 2017. The order provided for a return on equity of 8.7% . Pennsylvania Jurisdiction Distribution Corporation’s Pennsylvania jurisdiction delivery rates are being charged to customers in accordance with a rate settlement approved by the PaPUC. The rate settlement does not specify any requirement to file a future rate case. FERC Jurisdiction Supply Corporation filed a Section 4 rate case on July 31, 2019 proposing rate increases to be effective September 1, 2019. The proposed rates reflect an annual cost of service of $295.4 million , a rate base of $970.8 million and a proposed cost of equity of 15% . The proposed rate increases are expected to be suspended, with an effective date of February 1, 2020, subject to refund. If the proposed rate increases finally approved at the end of the proceeding exceed the rates that were in effect at July 31, 2019, but are less than rates put into effect subject to refund on February 1, 2020, Supply Corporation would be required to refund the difference between the rates collected subject to refund and the final approved rates, with interest at the FERC-approved rate. If the rates approved at the end of the proceeding are lower than the rates in effect at July 31, 2019, such lower rates will become effective prospectively from the date of the applicable FERC order, and refunds with interest will be limited to the difference between the rates collected subject to refund and the rates in effect at July 31, 2019. In response to the FERC’s July 2018 Final Rule in RM18-11-000, et. al (Order No. 849), on December 6, 2018, Supply Corporation filed its Form 501-G, which addresses the impact of the 2017 Tax Reform Act, and advised the Commission that it would make a Section 4 rate filing no later than July 31, 2019, which it has done, thereby obviating the need for FERC to take any further action. Refer to Note 5 - Income Taxes for further discussion of the 2017 Tax Reform Act. Empire filed a Section 4 rate case on June 29, 2018, proposing rate increases to be effective August 1, 2018. Empire and its customers reached a settlement in principle in December 2018, and Empire’s subsequent motion to put in place those interim settlement rates, effective January 1, 2019, was approved by FERC’s Chief Administrative Law Judge on December 31, 2018. The settlement was approved May 3, 2019. The “black box” settlement provides for new, system-wide rates, and which, based on current contracts, is estimated to increase Empire’s revenues on a yearly basis by approximately $4.6 million . The settlement also provides new depreciation rates and a tiered transportation revenue sharing mechanism, beginning with Empire sharing 35% of transportation only revenues (net of certain excluded items) over $64.4 million up to Empire sharing 55% of those revenues over $68.4 million . Empire has also committed to undertake certain improvements to its electronic bulletin board and will convene regular customer meetings to address these and other improvements. Under the settlement, Empire and the other parties may not file to change rates until March 31, 2021, except that Empire may make a filing (to be effective November 1, 2020) under limited circumstances for contract changes with a large customer. Empire must file a Section 4 rate case no later than May 1, 2025.

Summary Of Significant Accoun_2

Summary Of Significant Accounting Policies (Policy)	9 Months Ended
	Jun. 30, 2019
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 Company uses proportionate consolidation when accounting for drilling arrangements related to oil and gas producing properties accounted for under the full cost method of accounting. 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 . In November 2016, the FASB issued authoritative guidance related to the presentation of restricted cash on the statement of cash flows. The new guidance requires restricted cash and cash equivalents be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows, and requires disclosure of how cash and cash equivalents on the statement of cash flows reconciles to the balance sheet. The Company considers Hedging Collateral Deposits to be restricted cash. The Company adopted this guidance effective October 1, 2018 on a retrospective basis. As a result, prior periods have been reclassified to conform to the current year presentation. Additional discussion is provided below at Consolidated Statement of Cash Flows. In March 2017, the FASB issued authoritative guidance related to the presentation of net periodic pension cost and net periodic postretirement benefit cost. The new guidance requires segregation of the service cost component from the other components of net periodic pension cost and net periodic postretirement benefit cost for financial reporting purposes. The service cost component is to be presented on the income statement in the same line items as other compensation costs included within Operating Expenses and the other components of net periodic pension cost and net periodic postretirement benefit cost are to be presented on the income statement below the subtotal labeled Operating Income (Loss). Under this guidance, the service cost component is eligible to be capitalized as part of the cost of inventory or property, plant and equipment while the other components of net periodic pension cost and net periodic postretirement benefit cost are generally not eligible for capitalization, unless allowed by a regulator. The Company adopted this guidance effective October 1, 2018. The Company applied the guidance retrospectively for the pension and postretirement benefit costs using amounts disclosed in prior period financial statement notes as estimates for the reclassifications in accordance with a practical expedient allowed under the guidance. For the quarter and nine months ended June 30, 2018, Operating Income increased $6.2 million and $28.6 million , respectively, and Other Income (Deductions) decreased by the same amounts as a result of the reclassifications. For the quarter and nine months ended June 30, 2019, Other Income (Deductions) includes $5.7 million and $25.5 million , respectively, of pension and postretirement benefit costs.
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, 2018 , 2017 and 2016 that are included in the Company's 2018 Form 10-K. The consolidated financial statements for the year ended September 30, 2019 will be audited by the Company's independent registered public accounting firm after the end of the fiscal year. The earnings for the nine months ended June 30, 2019 should not be taken as a prediction of earnings for the entire fiscal year ending September 30, 2019 . 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 8 – Business Segment Information.
Consolidated Statements of Cash Flows	Consolidated Statements of Cash Flows. The components, as reported on the Company’s Consolidated Balance Sheets, of the total cash, cash equivalents, and restricted cash presented on the Statement of Cash Flows are as follows (in thousands): Nine Months Ended Nine Months Ended Balance at October 1, 2018 Balance at June 30, 2019 Balance at October 1, 2017 Balance at June 30, 2018 Cash and Temporary Cash Investments $ 229,606 $ 87,515 $ 555,530 $ 313,307 Hedging Collateral Deposits 3,441 6,835 1,741 2,283 Cash, Cash Equivalents, and Restricted Cash $ 233,047 $ 94,350 $ 557,271 $ 315,590 The Company considers all highly liquid debt instruments purchased with a maturity date of generally three months or less to be cash equivalents. The Company’s restricted cash is composed entirely of amounts reported as Hedging Collateral Deposits on the Consolidated Balance Sheets. Hedging Collateral Deposits is an account title for cash held in margin accounts funded by the Company to serve as collateral for hedging positions. 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	Gas Stored Underground. In the Utility segment, gas stored underground is carried at lower of cost or net realizable value, on a LIFO method. Gas stored underground 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 $16.3 million at June 30, 2019 , 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 $82.0 million and $62.2 million at June 30, 2019 and September 30, 2018 , 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 June 30, 2019, the ceiling exceeded the book value of the oil and gas properties by approximately $566.8 million . In adjusting estimated future cash flows for hedging under the ceiling test at June 30, 2019 , estimated future net cash flows were decreased by $23.9 million .
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss. The components of Accumulated Other Comprehensive Loss and changes for the nine months ended June 30, 2019 and 2018, net of related tax effect, are as follows (amounts in parentheses indicate debits) (in thousands): 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 Three Months Ended June 30, 2019 Balance at April 1, 2019 $ 4,562 $ — $ (58,848 ) $ (54,286 ) Other Comprehensive Gains and Losses Before Reclassifications 24,376 — — 24,376 Amounts Reclassified From Other Comprehensive Income (Loss) (2,756 ) — — (2,756 ) Balance at June 30, 2019 $ 26,182 $ — $ (58,848 ) $ (32,666 ) Nine Months Ended June 30, 2019 Balance at October 1, 2018 $ (28,611 ) $ 7,437 $ (46,576 ) $ (67,750 ) Other Comprehensive Gains and Losses Before Reclassifications 38,185 — — 38,185 Amounts Reclassified From Other Comprehensive Income (Loss) 14,742 — — 14,742 Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities — (7,437 ) — (7,437 ) Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act 1,866 — (12,272 ) (10,406 ) Balance at June 30, 2019 $ 26,182 $ — $ (58,848 ) $ (32,666 ) Three Months Ended June 30, 2018 Balance at April 1, 2018 $ 3,841 $ 6,885 $ (58,486 ) $ (47,760 ) Other Comprehensive Gains and Losses Before Reclassifications (27,036 ) (163 ) — (27,199 ) Amounts Reclassified From Other Comprehensive Income (Loss) 2,563 — — 2,563 Balance at June 30, 2018 $ (20,632 ) $ 6,722 $ (58,486 ) $ (72,396 ) Nine Months Ended June 30, 2018 Balance at October 1, 2017 $ 20,801 $ 7,562 $ (58,486 ) $ (30,123 ) Other Comprehensive Gains and Losses Before Reclassifications (39,294 ) (568 ) — (39,862 ) Amounts Reclassified From Other Comprehensive Income (Loss) (2,139 ) (272 ) — (2,411 ) Balance at June 30, 2018 $ (20,632 ) $ 6,722 $ (58,486 ) $ (72,396 ) In February 2018, the FASB issued authoritative guidance that allows an entity to elect a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the 2017 Tax Reform Act and requires certain disclosures about stranded tax effects. The Company adopted this authoritative guidance effective January 1, 2019 and recorded a cumulative effect adjustment related to deferred income taxes associated with hedging activities and pension and post-retirement benefit obligations during the quarter ended March 31, 2019 to increase retained earnings by $10.4 million and decrease accumulated other comprehensive income by the same amount. In January 2016, the FASB issued authoritative guidance regarding the recognition and measurement of financial assets and liabilities. The authoritative guidance primarily affects the accounting for equity investments and the presentation and disclosure requirements for financial instruments. All equity investments in unconsolidated entities will be measured at fair value through earnings rather than through accumulated other comprehensive income. The Company adopted this authoritative guidance effective October 1, 2018 and, as called for by the modified retrospective method of adoption, recorded a cumulative effect adjustment during the quarter ended December 31, 2018 to increase retained earnings by $7.4 million and decrease accumulated other comprehensive income by the same amount.
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 nine months ended June 30, 2019 and 2018 are as follows (amounts in parentheses indicate debits to the income statement) (in thousands): 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 Three Months Ended June 30, Nine Months Ended June 30, 2019 2018 2019 2018 Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges: Commodity Contracts $4,091 ($3,249 ) ($18,692 ) $6,125 Operating Revenues Commodity Contracts — 5 (1,182 ) 952 Purchased Gas Foreign Currency Contracts (222 ) (527 ) (624 ) (1,500 ) Operating Revenues Gains (Losses) on Securities Available for Sale — — — 430 Other Income (Deductions) 3,869 (3,771 ) (20,498 ) 6,007 Total Before Income Tax (1,113 ) 1,208 5,756 (3,596 ) Income Tax Expense $2,756 ($2,563 ) ($14,742 ) $2,411 Net of Tax
Other Current Assets	Other Current Assets . The components of the Company’s Other Current Assets are as follows (in thousands): At June 30, 2019 At September 30, 2018 Prepayments $ 13,777 $ 10,770 Prepaid Property and Other Taxes 11,501 14,444 Federal Income Taxes Receivable 6,554 22,457 State Income Taxes Receivable 8,773 8,822 Fair Values of Firm Commitments 5,618 1,739 Regulatory Assets 9,829 9,792 $ 56,052 $ 68,024
Other Assets	Other Assets . The components of the Company’s Other Assets are as follows (in thousands): At June 30, 2019 At September 30, 2018 Federal Income Taxes Receivable $ 42,546 $ — Other 86 102 $ 42,632 $ 102
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 June 30, 2019 At September 30, 2018 Accrued Capital Expenditures $ 60,082 $ 38,354 Regulatory Liabilities 50,233 57,425 Reserve for Gas Replacement 16,251 — Liability for Royalty and Working Interests 19,846 12,062 Other 33,651 24,852 $ 180,063 $ 132,693
Earnings Per Common Share	Earnings Per Common Share. Basic earnings per common share is computed by dividing income or loss 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 had outstanding were SARs, restricted stock units and performance shares. For the quarter and nine months ended June 30, 2019, 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. SARs, restricted stock units and performance shares that are antidilutive are excluded from the calculation of diluted earnings per common share. There were 120,546 securities and 122,327 securities excluded as being antidilutive for the quarter and nine months ended June 30, 2019, respectively. There were 1,095,838 securities and 316,279 securities excluded as being antidilutive for the quarter and nine months ended June 30, 2018, respectively.
Stock-Based Compensation	Stock-Based Compensation. The Company granted 244,734 performance shares during the nine months ended June 30, 2019 . The weighted average fair value of such performance shares was $55.67 per share for the nine months ended June 30, 2019 . 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 nine months ended June 30, 2019 must meet a performance goal related to relative return on capital over a three-year performance cycle. 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 nine months ended June 30, 2019 must meet a performance goal related to relative total shareholder return over a three-year performance cycle. 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 total 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 total shareholder return performance shares ("TSR 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 the TSR 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 TSR performance shares awarded, the result of which is recorded as compensation expense over the vesting term of the award. The Company granted 112,608 nonperformance-based restricted stock units during the nine months ended June 30, 2019 . The weighted average fair value of such nonperformance-based restricted stock units was $49.70 per share for the nine months ended June 30, 2019 . 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 nonperformance-based restricted stock units do not entitle the participant to receive dividends during the vesting period. The accounting for nonperformance-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.
New Authoritative Accounting and Financial Reporting Guidance	New Authoritative Accounting and Financial Reporting Guidance. In February 2016, the FASB issued authoritative guidance, which has subsequently been amended, requiring organizations that lease assets to recognize on the balance sheet the assets and liabilities for the rights and obligations created by all leases, regardless of whether they are considered to be capital leases or operating leases. The FASB’s previous authoritative guidance required organizations that lease assets to recognize on the balance sheet the assets and liabilities for the rights and obligations created by capital leases while excluding operating leases from balance sheet recognition. The new authoritative guidance will be effective as of the Company’s first quarter of fiscal 2020, with early adoption permitted. The Company does not anticipate early adoption. The Company will adopt the new authoritative guidance using the optional transition method, which permits an entity to initially apply the new lease accounting standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. The Company plans to apply practical expedients provided in the authoritative guidance that allow, among other things, an entity not to reassess contracts that commenced prior to the adoption date and to exclude all land easement arrangements that exist prior to the adoption date from treatment under the guidance. The Company also expects to elect a policy not to recognize right of use assets and lease liabilities related to short-term leases. The Company has finalized a plan for the adoption and implementation of the authoritative guidance and performed an initial assessment of its existing leasing arrangements and other contractual obligations. The Company also continues to evaluate and document technical accounting issues, policy considerations, financial reporting and disclosure implications, and changes to internal controls and businesses processes. While the Company continues to assess the impact on its financial statements, the Company expects that adoption of the authoritative guidance will result in an increase to its assets and liabilities on its consolidated balance sheet. In August 2017, the FASB issued authoritative guidance which changes the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities and to simplify the application of hedge accounting. The new guidance will be effective as of the Company’s first quarter of fiscal 2020, with early adoption permitted. The Company does not expect adoption of this guidance to have a significant impact on its consolidated financial statements and is currently evaluating the impact of this guidance.

Summary Of Significant Accoun_3

Summary Of Significant Accounting Policies (Tables)	9 Months Ended
	Jun. 30, 2019
Accounting Policies [Abstract]
Schedule of Cash, Cash Equivalents and Restricted Cash	The components, as reported on the Company’s Consolidated Balance Sheets, of the total cash, cash equivalents, and restricted cash presented on the Statement of Cash Flows are as follows (in thousands): Nine Months Ended Nine Months Ended Balance at October 1, 2018 Balance at June 30, 2019 Balance at October 1, 2017 Balance at June 30, 2018 Cash and Temporary Cash Investments $ 229,606 $ 87,515 $ 555,530 $ 313,307 Hedging Collateral Deposits 3,441 6,835 1,741 2,283 Cash, Cash Equivalents, and Restricted Cash $ 233,047 $ 94,350 $ 557,271 $ 315,590
Components of Accumulated Other Comprehensive Loss	The components of Accumulated Other Comprehensive Loss and changes for the nine months ended June 30, 2019 and 2018, net of related tax effect, are as follows (amounts in parentheses indicate debits) (in thousands): 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 Three Months Ended June 30, 2019 Balance at April 1, 2019 $ 4,562 $ — $ (58,848 ) $ (54,286 ) Other Comprehensive Gains and Losses Before Reclassifications 24,376 — — 24,376 Amounts Reclassified From Other Comprehensive Income (Loss) (2,756 ) — — (2,756 ) Balance at June 30, 2019 $ 26,182 $ — $ (58,848 ) $ (32,666 ) Nine Months Ended June 30, 2019 Balance at October 1, 2018 $ (28,611 ) $ 7,437 $ (46,576 ) $ (67,750 ) Other Comprehensive Gains and Losses Before Reclassifications 38,185 — — 38,185 Amounts Reclassified From Other Comprehensive Income (Loss) 14,742 — — 14,742 Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities — (7,437 ) — (7,437 ) Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act 1,866 — (12,272 ) (10,406 ) Balance at June 30, 2019 $ 26,182 $ — $ (58,848 ) $ (32,666 ) Three Months Ended June 30, 2018 Balance at April 1, 2018 $ 3,841 $ 6,885 $ (58,486 ) $ (47,760 ) Other Comprehensive Gains and Losses Before Reclassifications (27,036 ) (163 ) — (27,199 ) Amounts Reclassified From Other Comprehensive Income (Loss) 2,563 — — 2,563 Balance at June 30, 2018 $ (20,632 ) $ 6,722 $ (58,486 ) $ (72,396 ) Nine Months Ended June 30, 2018 Balance at October 1, 2017 $ 20,801 $ 7,562 $ (58,486 ) $ (30,123 ) Other Comprehensive Gains and Losses Before Reclassifications (39,294 ) (568 ) — (39,862 ) Amounts Reclassified From Other Comprehensive Income (Loss) (2,139 ) (272 ) — (2,411 ) Balance at June 30, 2018 $ (20,632 ) $ 6,722 $ (58,486 ) $ (72,396 )
Schedule of Reclassifications Out of Accumulated Other Comprehensive Loss	The details about the reclassification adjustments out of accumulated other comprehensive loss for the nine months ended June 30, 2019 and 2018 are as follows (amounts in parentheses indicate debits to the income statement) (in thousands): 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 Three Months Ended June 30, Nine Months Ended June 30, 2019 2018 2019 2018 Gains (Losses) on Derivative Financial Instrument Cash Flow Hedges: Commodity Contracts $4,091 ($3,249 ) ($18,692 ) $6,125 Operating Revenues Commodity Contracts — 5 (1,182 ) 952 Purchased Gas Foreign Currency Contracts (222 ) (527 ) (624 ) (1,500 ) Operating Revenues Gains (Losses) on Securities Available for Sale — — — 430 Other Income (Deductions) 3,869 (3,771 ) (20,498 ) 6,007 Total Before Income Tax (1,113 ) 1,208 5,756 (3,596 ) Income Tax Expense $2,756 ($2,563 ) ($14,742 ) $2,411 Net of Tax
Schedule of Other Current Assets	The components of the Company’s Other Current Assets are as follows (in thousands): At June 30, 2019 At September 30, 2018 Prepayments $ 13,777 $ 10,770 Prepaid Property and Other Taxes 11,501 14,444 Federal Income Taxes Receivable 6,554 22,457 State Income Taxes Receivable 8,773 8,822 Fair Values of Firm Commitments 5,618 1,739 Regulatory Assets 9,829 9,792 $ 56,052 $ 68,024
Schedule of Other Assets	The components of the Company’s Other Assets are as follows (in thousands): At June 30, 2019 At September 30, 2018 Federal Income Taxes Receivable $ 42,546 $ — Other 86 102 $ 42,632 $ 102
Schedule of Other Accruals and Current Liabilities	The components of the Company’s Other Accruals and Current Liabilities are as follows (in thousands): At June 30, 2019 At September 30, 2018 Accrued Capital Expenditures $ 60,082 $ 38,354 Regulatory Liabilities 50,233 57,425 Reserve for Gas Replacement 16,251 — Liability for Royalty and Working Interests 19,846 12,062 Other 33,651 24,852 $ 180,063 $ 132,693

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	9 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following tables provide a disaggregation of the Company's revenues for the quarter and nine months ended June 30, 2019 , presented by type of service from each reportable segment. Quarter Ended June 30, 2019 (Thousands) Revenues By Type of Service Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing All Other Corporate and Intersegment Eliminations Total Consolidated Production of Natural Gas $ 113,975 $ — $ — $ — $ — $ — $ — $ 113,975 Production of Crude Oil 38,823 — — — — — — 38,823 Natural Gas Processing 731 — — — — — — 731 Natural Gas Gathering Services — — 32,875 — — — (32,875 ) — Natural Gas Transportation Service — 50,001 — 23,010 — — (17,672 ) 55,339 Natural Gas Storage Service — 18,598 — — — — (8,060 ) 10,538 Natural Gas Residential Sales — — — 96,146 — — — 96,146 Natural Gas Commercial Sales — — — 12,107 — — — 12,107 Natural Gas Industrial Sales — — — 1,032 — — — 1,032 Natural Gas Marketing — — — — 22,212 — (681 ) 21,531 Other 152 368 — 161 5 854 (20 ) 1,520 Total Revenues from Contracts with Customers 153,681 68,967 32,875 132,456 22,217 854 (59,308 ) 351,742 Alternative Revenue Programs — — — 465 — — — 465 Derivative Financial Instruments 5,194 — — — (201 ) — — 4,993 Total Revenues $ 158,875 $ 68,967 $ 32,875 $ 132,921 $ 22,016 $ 854 $ (59,308 ) $ 357,200 Nine Months Ended June 30, 2019 (Thousands) Revenues By Type of Service Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing All Other Corporate and Intersegment Eliminations Total Consolidated Production of Natural Gas $ 371,710 $ — $ — $ — $ — $ — $ — $ 371,710 Production of Crude Oil 111,256 — — — — — — 111,256 Natural Gas Processing 2,676 — — — — — — 2,676 Natural Gas Gathering Services — — 91,931 — — — (91,931 ) — Natural Gas Transportation Service — 158,376 — 103,723 — — (54,556 ) 207,543 Natural Gas Storage Service — 56,887 — — — — (24,367 ) 32,520 Natural Gas Residential Sales — — — 492,267 — — — 492,267 Natural Gas Commercial Sales — — — 68,408 — — — 68,408 Natural Gas Industrial Sales — — — 4,400 — — — 4,400 Natural Gas Marketing — — — — 130,015 — (1,056 ) 128,959 Other 1,028 3,112 2 (8,662 ) 15 2,170 (529 ) (2,864 ) Total Revenues from Contracts with Customers 486,670 218,375 91,933 660,136 130,030 2,170 (172,439 ) 1,416,875 Alternative Revenue Programs — — — (1,528 ) — — — (1,528 ) Derivative Financial Instruments (18,817 ) — — — 3,461 — — (15,356 ) Total Revenues $ 467,853 $ 218,375 $ 91,933 $ 658,608 $ 133,491 $ 2,170 $ (172,439 ) $ 1,399,991

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	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 June 30, 2019 and September 30, 2018 . 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 combines gas and oil swaps 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 June 30, 2019 (Thousands of Dollars) Level 1 Level 2 Level 3 Netting Adjustments (1) Total (1) Assets: Cash Equivalents – Money Market Mutual Funds $ 75,375 $ — $ — $ — $ 75,375 Derivative Financial Instruments: Commodity Futures Contracts – Gas 1,367 — — (1,367 ) — Over the Counter Swaps – Gas and Oil — 44,929 — (6,850 ) 38,079 Foreign Currency Contracts — 78 — (1,500 ) (1,422 ) Other Investments: Balanced Equity Mutual Fund 40,313 — — — 40,313 Fixed Income Mutual Fund 55,034 — — — 55,034 Common Stock – Financial Services Industry 1,841 — — — 1,841 Hedging Collateral Deposits 6,835 — — — 6,835 Total $ 180,765 $ 45,007 $ — $ (9,717 ) $ 216,055 Liabilities: Derivative Financial Instruments: Commodity Futures Contracts – Gas $ 5,686 $ — $ — $ (1,367 ) $ 4,319 Over the Counter Swaps – Gas and Oil — 7,071 — (6,850 ) 221 Foreign Currency Contracts — 1,523 — (1,500 ) 23 Total $ 5,686 $ 8,594 $ — $ (9,717 ) $ 4,563 Total Net Assets/(Liabilities) $ 175,079 $ 36,413 $ — $ — $ 211,492 Recurring Fair Value Measures At fair value as of September 30, 2018 (Thousands of Dollars) Level 1 Level 2 Level 3 Netting Adjustments (1) Total (1) Assets: Cash Equivalents – Money Market Mutual Funds $ 215,272 $ — $ — $ — $ 215,272 Derivative Financial Instruments: Commodity Futures Contracts – Gas 1,075 — — (1,075 ) — Over the Counter Swaps – Gas and Oil — 26,074 — (17,041 ) 9,033 Foreign Currency Contracts — 443 — (443 ) — Other Investments: Balanced Equity Mutual Fund 38,468 — — — 38,468 Fixed Income Mutual Fund 51,331 — — — 51,331 Common Stock – Financial Services Industry 2,776 — — — 2,776 Hedging Collateral Deposits 3,441 — — — 3,441 Total $ 312,363 $ 26,517 $ — $ (18,559 ) $ 320,321 Liabilities: Derivative Financial Instruments: Commodity Futures Contracts – Gas $ 2,412 $ — $ — $ (1,075 ) $ 1,337 Over the Counter Swaps – Gas and Oil — 64,224 — (17,041 ) 47,183 Foreign Currency Contracts — 959 — (443 ) 516 Total $ 2,412 $ 65,183 $ — $ (18,559 ) $ 49,036 Total Net Assets/(Liabilities) $ 309,951 $ (38,666 ) $ — $ — $ 271,285 (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 (Tables)

Financial Instruments (Tables)	9 Months Ended
	Jun. 30, 2019
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): June 30, 2019 September 30, 2018 Carrying Amount Fair Value Carrying Amount Fair Value Long-Term Debt $ 2,133,101 $ 2,252,231 $ 2,131,365 $ 2,121,861
Schedule Of Other Investments	The components of the Company's Other Investments are as follows (in thousands): At June 30, 2019 At September 30, 2018 Life Insurance Contracts $ 40,659 $ 39,970 Equity Mutual Fund 40,313 38,468 Fixed Income Mutual Fund 55,034 51,331 Marketable Equity Securities 1,841 2,776 $ 137,847 $ 132,545
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 June 30, 2019 and 2018 (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 June 30, 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 June 30, 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 June 30, 2019 2018 2019 2018 2019 2018 Commodity Contracts $ 33,531 $ (35,976 ) Operating Revenue $ 4,091 $ (3,249 ) Operating Revenue $ 1,020 $ (339 ) Commodity Contracts 150 124 Purchased Gas — 5 Not Applicable — — Foreign Currency Contracts 530 (1,600 ) Operating Revenue (222 ) (527 ) Not Applicable — — Total $ 34,211 $ (37,452 ) $ 3,869 $ (3,771 ) $ 1,020 $ (339 ) The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the Nine Months Ended June 30, 2019 and 2018 (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 Nine Months Ended June 30, 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 Nine Months Ended June 30, 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 Nine Months Ended June 30, 2019 2018 2019 2018 2019 2018 Commodity Contracts $ 56,356 $ (52,440 ) Operating Revenue $ (18,692 ) $ 6,125 Operating Revenue $ 783 $ (436 ) Commodity Contracts (1,183 ) 737 Purchased Gas (1,182 ) 952 Not Applicable — — Foreign Currency Contracts (1,554 ) (3,831 ) Operating Revenue (624 ) (1,500 ) Not Applicable — — Total $ 53,619 $ (55,534 ) $ (20,498 ) $ 5,577 $ 783 $ (436 )
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 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 Nine Months Ended June 30, 2019 (In Thousands) Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income for the Nine Months Ended June 30, 2019 (In Thousands) Commodity Contracts Operating Revenues $ (3,507 ) $ 3,507 Commodity Contracts Purchased Gas $ 240 $ (240 ) $ (3,267 ) $ 3,267

Capitalization (Tables)

Capitalization (Tables)	9 Months Ended
	Jun. 30, 2019
Capitalization, Long-term Debt and Equity [Abstract]
Summary of Changes in Common Stock Equity	Summary of Changes in Common Stock Equity Common Stock Paid In Capital Earnings Reinvested in the Business Accumulated Other Comprehensive Income (Loss) Shares Amount (Thousands, except per share amounts) Balance at April 1, 2019 86,301 $ 86,301 $ 821,837 $ 1,236,657 $ (54,286 ) Net Income Available for Common Stock 63,753 Dividends Declared on Common Stock ($0.435 Per Share) (37,543 ) Other Comprehensive Income, Net of Tax 21,620 Share-Based Payment Expense (1) 5,054 Common Stock Issued Under Stock and Benefit Plans 6 6 352 Balance at June 30, 2019 86,307 $ 86,307 $ 827,243 $ 1,262,867 $ (32,666 ) Balance at October 1, 2018 85,957 $ 85,957 $ 820,223 $ 1,098,900 $ (67,750 ) Net Income Available for Common Stock 257,009 Dividends Declared on Common Stock ($1.285 Per Share) (110,885 ) Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities 7,437 Cumulative Effect of Adoption of Authoritative Guidance for Reclassification of Stranded Tax Effects 10,406 Other Comprehensive Income, Net of Tax 35,084 Share-Based Payment Expense (1) 15,008 Common Stock Issued (Repurchased) Under Stock and Benefit Plans 350 350 (7,988 ) Balance at June 30, 2019 86,307 $ 86,307 $ 827,243 $ 1,262,867 $ (32,666 ) Balance at April 1, 2018 85,882 $ 85,882 $ 810,126 $ 1,070,939 $ (47,760 ) Net Income Available for Common Stock 63,025 Dividends Declared on Common Stock ($0.425 Per Share) (36,526 ) Other Comprehensive Loss, Net of Tax (24,636 ) Share-Based Payment Expense (1) 3,558 Common Stock Issued Under Stock and Benefit Plans 62 62 2,711 Balance at June 30, 2018 85,944 $ 85,944 $ 816,395 $ 1,097,438 $ (72,396 ) Balance at October 1, 2017 85,543 $ 85,543 $ 796,646 $ 851,669 $ (30,123 ) Net Income Available for Common Stock 353,527 Dividends Declared on Common Stock ($1.255 Per Share) (107,758 ) Other Comprehensive Loss, Net of Tax (42,273 ) Share-Based Payment Expense (1) 10,632 Common Stock Issued Under Stock and Benefit Plans 401 401 9,117 Balance at June 30, 2018 85,944 $ 85,944 $ 816,395 $ 1,097,438 $ (72,396 ) (1) Paid in Capital includes compensation costs associated with performance shares and/or restricted stock awards. The expense is included within Net Income Available For Common Stock, net of tax benefits.

Business Segment Information (T

Business Segment Information (Tables)	9 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Financial Segment Information By Segment	A listing of segment assets at June 30, 2019 and September 30, 2018 is shown in the tables below. Quarter Ended June 30, 2019 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $158,875 $46,024 $— $129,977 $21,335 $356,211 $854 $135 $357,200 Intersegment Revenues $— $22,943 $32,875 $2,944 $681 $59,443 $— $(59,443) $— Segment Profit: Net Income (Loss) $26,512 $15,792 $14,638 $7,362 $(1,441) $62,863 $(3) $893 $63,753 Nine Months Ended June 30, 2019 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $467,853 $148,663 $2 $648,624 $132,435 $1,397,577 $2,170 $244 $1,399,991 Intersegment Revenues $— $69,712 $91,931 $9,984 $1,056 $172,683 $— $(172,683) $— Segment Profit: Net Income (Loss) $86,599 $58,643 $41,511 $68,600 $(1,198) $254,155 $252 $2,602 $257,009 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Segment Assets: At June 30, 2019 $1,847,706 $1,894,824 $555,185 $1,967,123 $45,736 $6,310,574 $78,528 $(52,855) $6,336,247 At September 30, 2018 $1,568,563 $1,848,180 $533,608 $1,921,971 $50,971 $5,923,293 $78,109 $35,084 $6,036,486 Quarter Ended June 30, 2018 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $135,828 $51,363 $(31) $128,628 $25,460 $341,248 $1,496 $168 $342,912 Intersegment Revenues $— $22,496 $27,908 $3,519 $512 $54,435 $— $(54,435) $— Segment Profit: Net Income (Loss) $27,817 $20,723 $11,566 $3,930 $(190) $63,846 $297 $(1,118) $63,025 Nine Months Ended June 30, 2018 (Thousands) Exploration and Production Pipeline and Storage Gathering Utility Energy Marketing Total Reportable Segments All Other Corporate and Intersegment Eliminations Total Consolidated Revenue from External Customers $421,381 $158,387 $41 $599,495 $119,739 $1,299,043 $3,824 $606 $1,303,473 Intersegment Revenues $— $67,524 $79,404 $11,401 $589 $158,918 $— $(158,918) $— Segment Profit: Net Income (Loss) $161,052 $81,909 $68,736 $58,283 $1,434 $371,414 $(214) $(17,673) $353,527

Retirement Plan And Other Pos_2

Retirement Plan And Other Post-Retirement Benefits (Tables)	9 Months Ended
	Jun. 30, 2019
Retirement Benefits [Abstract]
Components of Net Periodic Benefit Cost	Components of Net Periodic Benefit Cost (in thousands): Retirement Plan Other Post-Retirement Benefits Three Months Ended June 30, 2019 2018 2019 2018 Service Cost $ 2,120 $ 2,480 $ 380 $ 458 Interest Cost 9,594 8,252 4,286 3,700 Expected Return on Plan Assets (15,591 ) (15,429 ) (7,539 ) (7,871 ) Amortization of Prior Service Cost (Credit) 206 235 (107 ) (107 ) Amortization of Losses 8,024 9,301 1,490 2,639 Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1) (113 ) 712 3,757 3,386 Net Periodic Benefit Cost $ 4,240 $ 5,551 $ 2,267 $ 2,205 Retirement Plan Other Post-Retirement Benefits Nine Months Ended June 30, 2019 2018 2019 2018 Service Cost $ 6,362 $ 7,441 $ 1,140 $ 1,373 Interest Cost 28,783 24,754 12,858 11,101 Expected Return on Plan Assets (46,775 ) (46,286 ) (22,618 ) (23,612 ) Amortization of Prior Service Cost (Credit) 619 703 (321 ) (322 ) Amortization of Losses 24,072 27,904 4,471 7,918 Net Amortization and Deferral for Regulatory Purposes (Including Volumetric Adjustments) (1) 5,490 8,926 14,294 13,243 Net Periodic Benefit Cost $ 18,551 $ 23,442 $ 9,824 $ 9,701 (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 Accoun_4

Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2019
Summary Of Significant Accounting Policies [Line Items]
Pension and Postretirement Benefit Costs in Other Income and Deductions	$ 5,700	$ 6,200	$ 25,500	$ 28,600
Gas stored underground	$ (17,075)		(17,075)		$ (37,813)
Capitalized costs of unproved properties excluded from amortization			$ 82,000		62,200
Full cost ceiling test discount factor	10.00%		10.00%
Amount Full Cost Ceiling Exceeds Book Value Of Oil And Gas Properties	$ 566,800		$ 566,800
Decrease estimated future net cash flows	$ 23,900
Antidilutive securities	120,546	1,095,838	122,327	316,279
Reserve For Gas Replacement [Member]
Summary Of Significant Accounting Policies [Line Items]
Gas stored underground	$ 16,251		$ 16,251		$ 0
Non-performance Based Restricted Stock Units [Member]
Summary Of Significant Accounting Policies [Line Items]
Share based compensation other than options grants in period			112,608
Granted in fiscal year, weighted average grant date fair value			$ 49.70
Performance Shares [Member]
Summary Of Significant Accounting Policies [Line Items]
Share based compensation other than options grants in period			244,734
Granted in fiscal year, weighted average grant date fair value			$ 55.67
Subsequent Event [Member] | Reserve For Gas Replacement [Member]
Summary Of Significant Accounting Policies [Line Items]
Gas stored underground						$ 0
Guidance for Reclassification of Stranded Tax Effects [Member]
Summary Of Significant Accounting Policies [Line Items]
Cumulative Effect of Adoption of Authoritative Guidance	10,400		$ 10,400
Guidance for Recognition and Measurement of Financial Assets and Liabilities [Member]
Summary Of Significant Accounting Policies [Line Items]
Cumulative Effect of Adoption of Authoritative Guidance	$ 7,400		$ 7,400

Summary Of Significant Accoun_5

Summary Of Significant Accounting Policies (Consolidated Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	Jun. 30, 2019		Sep. 30, 2018		Jun. 30, 2018	Sep. 30, 2017
Cash and Cash Equivalents [Line Items]
Cash and Temporary Cash Investments	$ 87,515		$ 229,606		$ 313,307	$ 555,530
Hedging Collateral Deposits	6,835	[1]	3,441	[1]	2,283	1,741
Cash, Cash Equivalents and Restricted Cash	$ 94,350		$ 233,047		$ 315,590	$ 557,271
[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 Accoun_6

Summary Of Significant Accounting Policies (Components Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Loss [Roll Forward]
Balance at Beginning of Period	$ (54,286)	$ (47,760)	$ (67,750)	$ (30,123)
Other Comprehensive Gains and Losses Before Reclassifications	24,376	(27,199)	38,185	(39,862)
Amounts Reclassified From Other Comprehensive Income (Loss)	(2,756)	2,563	14,742	(2,411)
Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities			(7,437)
Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act	0	0	(10,406)	0
Balance at End of Period	(32,666)	(72,396)	(32,666)	(72,396)
Gains And Losses On Derivative Financial Instruments [Member]
Accumulated Other Comprehensive Loss [Roll Forward]
Balance at Beginning of Period	4,562	3,841	(28,611)	20,801
Other Comprehensive Gains and Losses Before Reclassifications	24,376	(27,036)	38,185	(39,294)
Amounts Reclassified From Other Comprehensive Income (Loss)	(2,756)	2,563	14,742	(2,139)
Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities			0
Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act			1,866
Balance at End of Period	26,182	(20,632)	26,182	(20,632)
Gains And Losses On Securities Available For Sale [Member]
Accumulated Other Comprehensive Loss [Roll Forward]
Balance at Beginning of Period	0	6,885	7,437	7,562
Other Comprehensive Gains and Losses Before Reclassifications	0	(163)	0	(568)
Amounts Reclassified From Other Comprehensive Income (Loss)	0	0	0	(272)
Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities			(7,437)
Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act			0
Balance at End of Period	0	6,722	0	6,722
Funded Status Of The Pension And Other Post-Retirement Benefit Plans [Member]
Accumulated Other Comprehensive Loss [Roll Forward]
Balance at Beginning of Period	(58,848)	(58,486)	(46,576)	(58,486)
Other Comprehensive Gains and Losses Before Reclassifications	0	0	0	0
Amounts Reclassified From Other Comprehensive Income (Loss)	0	0	0	0
Reclassification Adjustment for the Cumulative Effect of Adoption of Authoritative Guidance for Financial Assets and Liabilities			0
Reclassification of Stranded Tax Effects Related to the 2017 Tax Reform Act			(12,272)
Balance at End of Period	$ (58,848)	$ (58,486)	$ (58,848)	$ (58,486)

Summary Of Significant Accoun_7

Summary Of Significant Accounting Policies (Reclassification Out Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	$ 357,200	$ 342,912	$ 1,399,991	$ 1,303,473
Other Income (Deductions)	(1,456)	(3,612)	(16,977)	(20,205)
Income Before Income Taxes	84,866	82,208	330,815	329,702
Income Tax Expense	(21,113)	(19,183)	(73,806)	23,825
Net Income Available for Common Stock	63,753	63,025	257,009	353,527
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Income Before Income Taxes	3,869	(3,771)	(20,498)	6,007
Income Tax Expense	(1,113)	1,208	5,756	(3,596)
Net Income Available for Common Stock	2,756	(2,563)	(14,742)	2,411
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Gains And Losses On Securities Available For Sale [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Other Income (Deductions)	0	0	0	430
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 Loss [Line Items]
Operating Revenues	4,091	(3,249)	(18,692)	6,125
Foreign Currency Contracts [Member] | 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 Loss [Line Items]
Operating Revenues	(222)	(527)	(624)	(1,500)
Purchased Gas [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Purchased Gas	47,839	52,211	381,537	322,854
Purchased Gas [Member] | 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 Loss [Line Items]
Purchased Gas	$ 0	$ 5	$ (1,182)	$ 952

Summary Of Significant Accoun_8

Summary Of Significant Accounting Policies (Components Of Other Current Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Summary Of Significant Accounting Policies [Line Items]
Prepayments	$ 13,777	$ 10,770
Prepaid Property and Other Taxes	11,501	14,444
Fair Values of Firm Commitments	5,618	1,739
Regulatory Assets	9,829	9,792
Other Current Assets	56,052	68,024
State [Member]
Summary Of Significant Accounting Policies [Line Items]
Income Taxes Receivable	8,773	8,822
Other Current Assets [Member] | Federal [Member]
Summary Of Significant Accounting Policies [Line Items]
Income Taxes Receivable	$ 6,554	$ 22,457

Summary Of Significant Accoun_9

Summary Of Significant Accounting Policies (Other Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Other Assets [Line Items]
Other	$ 86	$ 102
Other Assets	42,632	102
Other Noncurrent Assets [Member] | Federal [Member]
Other Assets [Line Items]
Income Taxes Receivable	$ 42,546	$ 0

Summary Of Significant Accou_10

Summary Of Significant Accounting Policies (Schedule Of Other Accruals And Current Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Summary Of Significant Accounting Policies [Line Items]
Regulatory Liabilities	$ 50,233	$ 57,425
Reserve for Gas Replacement	(17,075)	(37,813)
Liability for Royalty and Working Interests	19,846	12,062
Other Accruals and Current Liabilities	180,063	132,693
Accrued Capital Expenditures [Member]
Summary Of Significant Accounting Policies [Line Items]
Other	60,082	38,354
Reserve For Gas Replacement [Member]
Summary Of Significant Accounting Policies [Line Items]
Reserve for Gas Replacement	16,251	0
Other Accruals [Member]
Summary Of Significant Accounting Policies [Line Items]
Other	$ 33,651	$ 24,852

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Narrative) (Details) $ in Millions	Jun. 30, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Future Revenue Amounts Related to Remaining Performance Obligations	$ 41.8
Remaining Performance Obligation, Expected Timing of Satisfaction	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Future Revenue Amounts Related to Remaining Performance Obligations	$ 158.9
Remaining Performance Obligation, Expected Timing of Satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Future Revenue Amounts Related to Remaining Performance Obligations	$ 135.3
Remaining Performance Obligation, Expected Timing of Satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Future Revenue Amounts Related to Remaining Performance Obligations	$ 114.1
Remaining Performance Obligation, Expected Timing of Satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Future Revenue Amounts Related to Remaining Performance Obligations	$ 82.3
Remaining Performance Obligation, Expected Timing of Satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Future Revenue Amounts Related to Remaining Performance Obligations	$ 370.5
Remaining Performance Obligation, Expected Timing of Satisfaction

Revenue from Contracts with C_4

Revenue from Contracts with Customers (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 357,200	$ 342,912	$ 1,399,991	$ 1,303,473
Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	153,681		486,670
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	5,194		(18,817)
Revenue	158,875		467,853
Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	68,967		218,375
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Revenue	68,967		218,375
Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	32,875		91,933
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Revenue	32,875		91,933
Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	132,456		660,136
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	465		(1,528)
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Revenue	132,921		658,608
Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	22,217		130,030
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	(201)		3,461
Revenue	22,016		133,491
All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	854		2,170
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Revenue	854		2,170
Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	(59,308)		(172,439)
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	0		0
Revenue	(59,308)		(172,439)
Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	351,742		1,416,875
Alternative Revenue Programs Outside Scope of Authoritative Guidance on Revenue Recognition	465		(1,528)
Derivative Financial Instruments Outside Scope of Authoritative Guidance on Revenue Recognition	4,993		(15,356)
Revenue	357,200		1,399,991
Production of Natural Gas [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	113,975		371,710
Production of Natural Gas [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Natural Gas [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Natural Gas [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Natural Gas [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Natural Gas [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Natural Gas [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Natural Gas [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	113,975		371,710
Production of Crude Oil [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	38,823		111,256
Production of Crude Oil [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Crude Oil [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Crude Oil [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Crude Oil [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Crude Oil [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Crude Oil [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Production of Crude Oil [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	38,823		111,256
Natural Gas Processing [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	731		2,676
Natural Gas Processing [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Processing [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Processing [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Processing [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Processing [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Processing [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Processing [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	731		2,676
Natural Gas Gathering Services [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Gathering Services [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Gathering Services [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	32,875		91,931
Natural Gas Gathering Services [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Gathering Services [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Gathering Services [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Gathering Services [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	(32,875)		(91,931)
Natural Gas Gathering Services [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Transportation Service [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Transportation Service [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	50,001		158,376
Natural Gas Transportation Service [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Transportation Service [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	23,010		103,723
Natural Gas Transportation Service [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Transportation Service [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Transportation Service [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	(17,672)		(54,556)
Natural Gas Transportation Service [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	55,339		207,543
Natural Gas Storage Service [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Storage Service [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	18,598		56,887
Natural Gas Storage Service [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Storage Service [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Storage Service [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Storage Service [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Storage Service [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	(8,060)		(24,367)
Natural Gas Storage Service [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	10,538		32,520
Natural Gas Residential Sales [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Residential Sales [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Residential Sales [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Residential Sales [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	96,146		492,267
Natural Gas Residential Sales [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Residential Sales [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Residential Sales [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Residential Sales [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	96,146		492,267
Natural Gas Commercial Sales [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Commercial Sales [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Commercial Sales [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Commercial Sales [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	12,107		68,408
Natural Gas Commercial Sales [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Commercial Sales [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Commercial Sales [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Commercial Sales [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	12,107		68,408
Natural Gas Industrial Sales [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Industrial Sales [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Industrial Sales [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Industrial Sales [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,032		4,400
Natural Gas Industrial Sales [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Industrial Sales [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Industrial Sales [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Industrial Sales [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,032		4,400
Natural Gas Marketing [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Marketing [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Marketing [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Marketing [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Marketing [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	22,212		130,015
Natural Gas Marketing [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		0
Natural Gas Marketing [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	(681)		(1,056)
Natural Gas Marketing [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	21,531		128,959
Other [Member] | Exploration And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	152		1,028
Other [Member] | Pipeline And Storage [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	368		3,112
Other [Member] | Gathering [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0		2
Other [Member] | Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	161		(8,662)
Other [Member] | Energy Marketing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	5		15
Other [Member] | All Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	854		2,170
Other [Member] | Corporate And Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	(20)		(529)
Other [Member] | Total Consolidated [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 1,520		$ (2,864)

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	Jun. 30, 2019		Sep. 30, 2018		Jun. 30, 2018	Sep. 30, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedging collateral deposits	$ 6,835,000	[1]	$ 3,441,000	[1]	$ 2,283,000	$ 1,741,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedging collateral deposits	6,835,000		3,441,000
Fair Value, Inputs, Level 1 [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedging collateral deposits	6,800,000		$ 3,400,000
Derivative Financial Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Level 3 Fair Value	0				0
Level 1 or Level 2 Transfers	$ 0				$ 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.

Fair Value Measurements (Recurr

Fair Value Measurements (Recurring Fair Value Measures Of Assets And Liabilities) (Details) - USD ($) $ in Thousands		Jun. 30, 2019		Sep. 30, 2018		Jun. 30, 2018	Sep. 30, 2017
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash Equivalents - Money Market Mutual Funds	[1]	$ 75,375		$ 215,272
Hedging Collateral Deposits		6,835	[1]	3,441	[1]	$ 2,283	$ 1,741
Total Assets	[1]	216,055		320,321
Total Liabilities	[1]	4,563		49,036
Total Net Assets/(Liabilities)	[1]	211,492		271,285
Commodity Futures Contracts - Gas [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	[1]	0		0
Derivative Liability	[1]	4,319		1,337
Over The Counter Swaps - Gas And Oil [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	[1]	38,079		9,033
Derivative Liability	[1]	221		47,183
Foreign Currency Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	[1]	(1,422)		0
Derivative Liability	[1]	23		516
Balanced Equity Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments	[1]	40,313		38,468
Fixed Income Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments	[1]	55,034		51,331
Common Stock - Financial Services Industry [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments	[1]	1,841		2,776
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash Equivalents - Money Market Mutual Funds		75,375		215,272
Hedging Collateral Deposits		6,835		3,441
Total Assets		180,765		312,363
Total Liabilities		5,686		2,412
Total Net Assets/(Liabilities)		175,079		309,951
Fair Value, Inputs, Level 1 [Member] | Commodity Futures Contracts - Gas [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset		1,367		1,075
Derivative Liability		5,686		2,412
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 Asset		0		0
Derivative Liability		0		0
Fair Value, Inputs, Level 1 [Member] | Foreign Currency Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset		0		0
Derivative Liability		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		40,313		38,468
Fair Value, Inputs, Level 1 [Member] | Fixed Income Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments		55,034		51,331
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		1,841		2,776
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		45,007		26,517
Total Liabilities		8,594		65,183
Total Net Assets/(Liabilities)		36,413		(38,666)
Fair Value, Inputs, Level 2 [Member] | Commodity Futures Contracts - Gas [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset		0		0
Derivative Liability		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 Asset		44,929		26,074
Derivative Liability		7,071		64,224
Fair Value, Inputs, Level 2 [Member] | Foreign Currency Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset		78		443
Derivative Liability		1,523		959
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] | Fixed Income 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 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		0		0
Total Liabilities		0		0
Total Net Assets/(Liabilities)		0		0
Fair Value, Inputs, Level 3 [Member] | Commodity Futures Contracts - Gas [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset		0		0
Derivative Liability		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 Asset		0		0
Derivative Liability		0		0
Fair Value, Inputs, Level 3 [Member] | Foreign Currency Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset		0		0
Derivative Liability		0		0
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] | Fixed Income 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
Netting Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Cash Equivalents - Money Market Mutual Funds	[1]	0		0
Hedging Collateral Deposits	[1]	0		0
Total Assets	[1]	(9,717)		(18,559)
Total Liabilities	[1]	(9,717)		(18,559)
Total Net Assets/(Liabilities)	[1]	0		0
Netting Adjustments [Member] | Commodity Futures Contracts - Gas [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	[1]	(1,367)		(1,075)
Derivative Liability	[1]	(1,367)		(1,075)
Netting Adjustments [Member] | Over The Counter Swaps - Gas And Oil [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	[1]	(6,850)		(17,041)
Derivative Liability	[1]	(6,850)		(17,041)
Netting Adjustments [Member] | Foreign Currency Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	[1]	(1,500)		(443)
Derivative Liability	[1]	(1,500)		(443)
Netting Adjustments [Member] | Balanced Equity Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments	[1]	0		0
Netting Adjustments [Member] | Fixed Income Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments	[1]	0		0
Netting Adjustments [Member] | Common Stock - Financial Services Industry [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Other Investments	[1]	$ 0		$ 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.

Financial Instruments (Narrativ

Financial Instruments (Narrative) (Details) $ in Thousands	9 Months Ended
	Jun. 30, 2019USD ($)counterpartyMMcfbbl		Sep. 30, 2018USD ($)	[1]	Jun. 30, 2018USD ($)	Sep. 30, 2017USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Foreign Currency Forward Contract Hedge Duration	7 years
Net hedging gains (losses) in accumulated other comprehensive income (loss)	$ 36,700
After tax net hedging gains (losses) in accumulated other comprehensive income (loss)	26,200
Pre-Tax Net Hedging Gains (Losses) Reclassified Within Twelve Months	28,700
After Tax Net Hedging Gains (Losses) Reclassified Within Twelve Months	20,500
Fair market value of derivative asset with a credit-risk related contingency	27,300
Fair market value of derivative liability with a credit-risk related contingency	200
Hedging collateral deposits	$ 6,835	[1]	$ 3,441		$ 2,283	$ 1,741
Cash Flow and Fair Value Commodity Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedge Duration	5 years
Over the Counter Swaps and Foreign Currency Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Number of counterparties in which the company holds over-the-counter swap positions | counterparty	18
Number of counterparties in net gain position | counterparty	17
Credit risk exposure per counterparty	$ 2,100
Maximum credit risk exposure per counterparty	6,100
Collateral Received by the Company	0
Hedging collateral deposits	$ 0
Withdrawal of Storage Gas Mmcf [Member] | Energy Marketing [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Nonmonetary notional amount of price risk fair value hedge derivatives, natural gas | MMcf	500
Fair Value Hedges MMCf [Member] | Energy Marketing [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Nonmonetary notional amount of price risk fair value hedge derivatives, natural gas | MMcf	24,800
Fixed Price Sales Commitments MMCf [Member] | Energy Marketing [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Nonmonetary notional amount of price risk fair value hedge derivatives, natural gas | MMcf	24,300
Natural Gas MMCf [Member] | Cash Flow Hedges Short Position [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Nonmonetary notional amount of price risk cash flow hedge derivatives, natural gas | MMcf	80,200
Natural Gas MMCf [Member] | Cash Flow Hedges Long Position [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Nonmonetary notional amount of price risk cash flow hedge derivatives, natural gas | MMcf	3,700
Crude Oil Bbls [Member] | Cash Flow Hedges Short Position [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Nonmonetary notional amount of price risk cash flow hedge derivatives, crude oil | bbl	3,225,000
Exchange Traded Futures Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedging collateral deposits	$ 6,800
Foreign Currency Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 79,700
Credit Risk Related Contingency Feature [Member] | Over the Counter Swaps and Foreign Currency Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Number of counterparties with a common credit-risk related contingency | counterparty	15
[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 (Long-Ter

Financial Instruments (Long-Term Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Financial Instruments, Owned, at Fair Value [Abstract]
Carrying Amount	$ 2,133,101	$ 2,131,365
Fair Value	$ 2,252,231	$ 2,121,861

Financial Investments (Other In

Financial Investments (Other Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Investment Holdings [Line Items]
Life Insurance Contracts	$ 40,659	$ 39,970
Other Investments	137,847	132,545
Equity Mutual Fund [Member]
Investment Holdings [Line Items]
Fair Value	40,313	38,468
Fixed Income Mutual Fund [Member]
Investment Holdings [Line Items]
Fair Value	55,034	51,331
Marketable Equity Securities [Member]
Investment Holdings [Line Items]
Fair Value	$ 1,841	$ 2,776

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 ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
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)	$ 34,211	$ (37,452)	$ 53,619	$ (55,534)
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)	3,869	(3,771)	(20,498)	5,577
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	1,020	(339)	783	(436)
Foreign Currency Contracts [Member] | Operating Revenues [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)	530	(1,600)	(1,554)	(3,831)
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)	(222)	(527)	(624)	(1,500)
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Commodity Contracts [Member] | Operating Revenues [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)	33,531	(35,976)	56,356	(52,440)
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)	4,091	(3,249)	(18,692)	6,125
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	1,020	(339)	783	(436)
Commodity Contracts [Member] | Purchased Gas [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)	150	124	(1,183)	737
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	5	(1,182)	952
Derivative Gain or (Loss) Recognized in the Consolidated Statement of Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)	$ 0	$ 0	$ 0	$ 0

Financial Instruments (Schedu_2

Financial Instruments (Schedule Of Derivatives And Hedged Items In Fair Value Hedging Relationships) (Details) $ in Thousands	9 Months Ended
	Jun. 30, 2019USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) on Derivative Recognized in the Consolidated Statement of Income	$ (3,267)
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	3,267
Operating Revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) on Derivative Recognized in the Consolidated Statement of Income	(3,507)
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	3,507
Purchased Gas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) on Derivative Recognized in the Consolidated Statement of Income	240
Amount of Gain or (Loss) on the Hedged Item Recognized in the Consolidated Statement of Income	$ (240)

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Income Taxes [Line Items]
Effective Tax Rate	24.90%	23.30%	22.30%	(7.20%)
Federal Statutory Rate			21.00%		24.50%	35.00%
Reduction to Income Tax Expense Due to Remeasurement of Deferred Income Tax Assets and Liabilities			$ 5,000		$ 103,500
Reduction In Deferred Taxes for Rate Regulated Activities Due to Remeasurement of Deferred Income Tax Assets and Liabilities					336,700
Decrease to Recoverable Future Taxes Due to Change in Corporate Tax Rate					65,700
Increase in Taxes Refundable to Customers Due to Change in Corporate Tax Rate					271,000
Federal [Member] | Other Noncurrent Assets [Member]
Income Taxes [Line Items]
Income Taxes Receivable	$ 42,546		$ 42,546		$ 0

Capitalization (Narrative) (Det

Capitalization (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Common stock shares issued due to SARs exercises	126,879
Shares tendered	159,137
Current Portion of Long-Term Debt	$ 0	$ 0
Restricted Stock Units [Member]
Debt Instrument [Line Items]
Common stock issued	79,654
Performance Shares [Member]
Debt Instrument [Line Items]
Common stock issued	281,882
Board Of Directors [Member]
Debt Instrument [Line Items]
Common stock issued	20,501

Capitalization and Short-Term B

Capitalization and Short-Term Borrowings (Summary of Changes in Common Stock Equity) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Schedule of Capitalization, Equity [Line Items]
Beginning balance (shares)				85,956,814
Beginning balance				$ 820,223
Balance at Beginning of Period		$ 1,236,657	$ 1,070,939	1,098,900	$ 851,669
Balance at Beginning of Period		(54,286)	(47,760)	(67,750)	(30,123)
Net Income Available for Common Stock		63,753	63,025	257,009	353,527
Dividends Declared on Common Stock		(37,543)	(36,526)	(110,885)	(107,758)
Other Comprehensive Income (Loss), Net of Tax		$ 21,620	(24,636)	$ 35,084	(42,273)
Ending balance (shares)		86,306,593		86,306,593
Ending balance		$ 827,243		$ 827,243
Balance at June 30		1,262,867	1,097,438	1,262,867	1,097,438
Balance at End of Period		(32,666)	(72,396)	(32,666)	(72,396)
Paid-in Capital [Member]
Schedule of Capitalization, Equity [Line Items]
Beginning balance		821,837	810,126	820,223	796,646
Share-Based Payment Expense	[1]	5,054	3,558	15,008	10,632
Common Stock Issued Under Stock and Benefit Plans (Value)		352	2,711		9,117
Common Stock Repurchased Under Stock and Benefit Plans, Value				(7,988)
Ending balance		827,243	816,395	827,243	816,395
Earnings Reinvested in The Business [Member]
Schedule of Capitalization, Equity [Line Items]
Balance at Beginning of Period		1,236,657	1,070,939	1,098,900	851,669
Net Income Available for Common Stock		63,753	63,025	257,009	353,527
Dividends Declared on Common Stock		(37,543)	(36,526)	(110,885)	(107,758)
Balance at June 30		1,262,867	1,097,438	1,262,867	1,097,438
Accumulated Other Comprehensive Income (Loss) [Member]
Schedule of Capitalization, Equity [Line Items]
Balance at Beginning of Period		(54,286)	(47,760)	(67,750)	(30,123)
Other Comprehensive Income (Loss), Net of Tax		21,620	(24,636)	35,084	(42,273)
Balance at End of Period		$ (32,666)	$ (72,396)	$ (32,666)	$ (72,396)
Common Stock [Member]
Schedule of Capitalization, Equity [Line Items]
Beginning balance (shares)		86,301,000	85,882,000	85,957,000	85,543,000
Beginning balance (value)		$ 86,301	$ 85,882	$ 85,957	$ 85,543
Common Stock Issued Under Stock and Benefit Plans (Shares)		6,000	62,000	350,000	401,000
Common Stock Issued Under Stock and Benefit Plans (Value)		$ 6	$ 62	$ 350	$ 401
Ending balance (shares)		86,307,000	85,944,000	86,307,000	85,944,000
Ending balance (value)		$ 86,307	$ 85,944	$ 86,307	$ 85,944
Guidance for Reclassification of Stranded Tax Effects [Member]
Schedule of Capitalization, Equity [Line Items]
Cumulative Effect of Adoption of Authoritative Guidance		10,400		10,400
Guidance for Reclassification of Stranded Tax Effects [Member] | Earnings Reinvested in The Business [Member]
Schedule of Capitalization, Equity [Line Items]
Cumulative Effect of Adoption of Authoritative Guidance		10,406		10,406
Guidance for Recognition and Measurement of Financial Assets and Liabilities [Member]
Schedule of Capitalization, Equity [Line Items]
Cumulative Effect of Adoption of Authoritative Guidance		7,400		7,400
Guidance for Recognition and Measurement of Financial Assets and Liabilities [Member] | Earnings Reinvested in The Business [Member]
Schedule of Capitalization, Equity [Line Items]
Cumulative Effect of Adoption of Authoritative Guidance		$ 7,437		$ 7,437
[1]	Paid in Capital includes compensation costs associated with performance shares and/or restricted stock awards. The expense is included within Net Income Available For Common Stock, net of tax benefits.

Commitments And Contingencies (

Commitments And Contingencies (Details) $ in Millions	9 Months Ended
	Jun. 30, 2019USD ($)
Site Contingency [Line Items]
Estimated minimum liability for environmental remediation	$ 7.1
Rate recovery period	3 years
Former Manufactured Gas Plant Site New York [Member]
Site Contingency [Line Items]
Estimated minimum liability for environmental remediation	$ 3.9

Business Segment Information (N

Business Segment Information (Narrative) (Details)	9 Months Ended
	Jun. 30, 2019segment
Segment Reporting [Abstract]
Number of reportable segments	5

Business Segment Information (F

Business Segment Information (Financial Segment Information By Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 357,200	$ 342,912	$ 1,399,991	$ 1,303,473
Segment Profit: Net Income (Loss)	63,753	63,025	257,009	353,527
Segment Assets	6,336,247		6,336,247		$ 6,036,486
Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	357,200	342,912	1,399,991	1,303,473
Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	0	0	0	0
Exploration And Production [Member]
Segment Reporting Information [Line Items]
Revenue	158,875		467,853
Segment Profit: Net Income (Loss)	26,512	27,817	86,599	161,052
Segment Assets	1,847,706		1,847,706		1,568,563
Exploration And Production [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	158,875	135,828	467,853	421,381
Exploration And Production [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	0	0	0	0
Pipeline And Storage [Member]
Segment Reporting Information [Line Items]
Revenue	68,967		218,375
Segment Profit: Net Income (Loss)	15,792	20,723	58,643	81,909
Segment Assets	1,894,824		1,894,824		1,848,180
Pipeline And Storage [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	46,024	51,363	148,663	158,387
Pipeline And Storage [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	22,943	22,496	69,712	67,524
Gathering [Member]
Segment Reporting Information [Line Items]
Revenue	32,875		91,933
Segment Profit: Net Income (Loss)	14,638	11,566	41,511	68,736
Segment Assets	555,185		555,185		533,608
Gathering [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	0	(31)	2	41
Gathering [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	32,875	27,908	91,931	79,404
Utility [Member]
Segment Reporting Information [Line Items]
Revenue	132,921		658,608
Segment Profit: Net Income (Loss)	7,362	3,930	68,600	58,283
Segment Assets	1,967,123		1,967,123		1,921,971
Utility [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	129,977	128,628	648,624	599,495
Utility [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	2,944	3,519	9,984	11,401
Energy Marketing [Member]
Segment Reporting Information [Line Items]
Revenue	22,016		133,491
Segment Profit: Net Income (Loss)	(1,441)	(190)	(1,198)	1,434
Segment Assets	45,736		45,736		50,971
Energy Marketing [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	21,335	25,460	132,435	119,739
Energy Marketing [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	681	512	1,056	589
Total Reportable Segments [Member]
Segment Reporting Information [Line Items]
Segment Profit: Net Income (Loss)	62,863	63,846	254,155	371,414
Segment Assets	6,310,574		6,310,574		5,923,293
Total Reportable Segments [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	356,211	341,248	1,397,577	1,299,043
Total Reportable Segments [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	59,443	54,435	172,683	158,918
All Other [Member]
Segment Reporting Information [Line Items]
Revenue	854		2,170
Segment Profit: Net Income (Loss)	(3)	297	252	(214)
Segment Assets	78,528		78,528		78,109
All Other [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	854	1,496	2,170	3,824
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]
Revenue	(59,308)		(172,439)
Segment Profit: Net Income (Loss)	893	(1,118)	2,602	(17,673)
Segment Assets	(52,855)		(52,855)		$ 35,084
Corporate And Intersegment Eliminations [Member] | Revenue from External Customers [Member]
Segment Reporting Information [Line Items]
Revenue	135	168	244	606
Corporate And Intersegment Eliminations [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	$ (59,443)	$ (54,435)	$ (172,683)	$ (158,918)

Retirement Plan And Other Pos_3

Retirement Plan And Other Post-Retirement Benefits (Narrative) (Details) $ in Millions	9 Months Ended
	Jun. 30, 2019USD ($)
Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's contributions	$ 29.2
VEBA Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's contributions	2.7
Estimated future contributions in remainder of fiscal year	0.2
Maximum [Member] | Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions in remainder of fiscal year	$ 5

Retirement Plan And Other Pos_4

Retirement Plan And Other Post-Retirement Benefits (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost		$ 2,120	$ 2,480	$ 6,362	$ 7,441
Interest Cost		9,594	8,252	28,783	24,754
Expected Return on Plan Assets		(15,591)	(15,429)	(46,775)	(46,286)
Amortization of Prior Service Cost (Credit)		206	235	619	703
Amortization of Losses		8,024	9,301	24,072	27,904
Net Amortization and Deferral For Regulatory Purposes (Including Volumetric Adjustments)	[1]	(113)	712	5,490	8,926
Net Periodic Benefit Cost		4,240	5,551	18,551	23,442
Other Post-Retirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost		380	458	1,140	1,373
Interest Cost		4,286	3,700	12,858	11,101
Expected Return on Plan Assets		(7,539)	(7,871)	(22,618)	(23,612)
Amortization of Prior Service Cost (Credit)		(107)	(107)	(321)	(322)
Amortization of Losses		1,490	2,639	4,471	7,918
Net Amortization and Deferral For Regulatory Purposes (Including Volumetric Adjustments)	[1]	3,757	3,386	14,294	13,243
Net Periodic Benefit Cost		$ 2,267	$ 2,205	$ 9,824	$ 9,701
[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) $ in Millions	9 Months Ended
	Jun. 30, 2019USD ($)
Regulatory Matters [Line Items]
Approved Return on Equity	8.70%
Supply Corporation [Member]
Regulatory Matters [Line Items]
Proposed Annual Cost of Service	$ 295.4
Proposed Rate Base	$ 970.8
Proposed Return on Equity	15.00%
Empire [Member]
Regulatory Matters [Line Items]
Estimated Increase to Revenues from Interim Rates	$ 4.6
Empire [Member] | Maximum [Member]
Regulatory Matters [Line Items]
Revenue Sharing Mechanism Percentage	55.00%
Revenue Sharing Mechanism Revenue Level	$ 68.4
Empire [Member] | Minimum [Member]
Regulatory Matters [Line Items]
Revenue Sharing Mechanism Percentage	35.00%
Revenue Sharing Mechanism Revenue Level	$ 64.4