Atmos Energy (ATO) 10-Q 8 Aug 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Jun. 30, 2018	Aug. 03, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Atmos Energy Corporation
Entity Central Index Key	731,802
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		111,200,632

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
ASSETS
Property, plant and equipment	$ 12,260,376	$ 11,301,304
Less accumulated depreciation and amortization	2,188,516	2,042,122
Net property, plant and equipment	10,071,860	9,259,182
Current assets
Cash and cash equivalents	20,930	26,409
Accounts receivable, net	253,546	222,263
Gas stored underground	126,010	184,653
Other current assets	52,369	106,321
Total current assets	452,855	539,646
Goodwill	730,132	730,132
Deferred charges and other assets	252,777	220,636
Total assets	11,507,624	10,749,596
Shareholders’ equity
Common stock, no par value (stated at $0.005 per share); 200,000,000 shares authorized; issued and outstanding: June 30, 2018 — 111,195,448 shares; September 30, 2017 — 106,104,634 shares	556	531
Additional paid-in capital	2,964,043	2,536,365
Accumulated other comprehensive loss	(76,381)	(105,254)
Retained earnings	1,871,334	1,467,024
Shareholders’ equity	4,759,552	3,898,666
Long-term debt	2,618,315	3,067,045
Total capitalization	7,377,867	6,965,711
Current liabilities
Accounts payable and accrued liabilities	198,172	233,050
Other current liabilities	573,012	332,648
Short-term debt	244,777	447,745
Current maturities of long-term debt	450,000	0
Total current liabilities	1,465,961	1,013,443
Deferred income taxes	1,133,622	1,878,699
Regulatory excess deferred taxes (See Note 6)	733,509	0
Regulatory cost of removal obligation	482,001	485,420
Pension and postretirement liabilities	239,946	230,588
Deferred credits and other liabilities	74,718	175,735
Total shareholders' equity and liabilities	$ 11,507,624	$ 10,749,596

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) - $ / shares	Jun. 30, 2018	Sep. 30, 2017
Statement of Financial Position [Abstract]
Common stock stated value (USD per share)	$ 0.005	$ 0.005
Common stock authorized (in shares)	200,000,000	200,000,000
Common stock issued (in shares)	111,195,448	106,104,634
Common stock outstanding (in shares)	111,195,448	106,104,634

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operating revenues
Total operating revenues	$ 562,245	$ 526,501	$ 2,670,846	$ 2,294,855
Purchased gas cost
Total purchased gas cost	130,886	114,176	1,124,763	852,975
Operation and maintenance expense	145,075	128,690	435,715	385,867
Depreciation and amortization expense	90,671	80,023	268,426	234,648
Taxes, other than income	72,620	62,948	208,400	185,611
Operating income	122,993	140,664	633,542	635,754
Miscellaneous expense	(2,003)	(289)	(4,291)	(450)
Interest charges	23,349	28,498	82,162	86,472
Income before income taxes	97,641	111,877	547,089	548,832
Income tax expense	26,448	41,069	(17,228)	201,974
Income from continuing operations	71,193	70,808	564,317	346,858
Income from discontinued operations, net of tax ($0 and $6,841)			0	10,994
Gain on sale of discontinued operations, net of tax ($0 and $10,215)			0	2,716
Net income	$ 71,193	$ 70,808	$ 564,317	$ 360,568
Income per share from continuing operations (USD per share)	$ 0.64	$ 0.67	$ 5.09	$ 3.27
Income per share from discontinued operations (USD per share)	0	0	0	0.13
Net income per share - basic and diluted (USD per share)	0.64	0.67	5.09	3.40
Cash dividends per share (USD per share)	$ 0.485	$ 0.450	$ 1.455	$ 1.350
Basic and diluted weighted average shares outstanding (in shares)	111,851	106,364	110,707	105,862
Operating Segments | Distribution segment
Operating revenues
Total operating revenues	$ 535,488	$ 494,060	$ 2,595,571	$ 2,211,257
Purchased gas cost
Total purchased gas cost	230,887	197,767	1,421,698	1,106,209
Operation and maintenance expense	111,895	99,631	347,623	296,048
Depreciation and amortization expense	66,504	62,760	197,587	185,219
Taxes, other than income	64,420	56,850	184,219	165,032
Operating income	61,782	77,052	444,444	458,749
Miscellaneous expense	(1,191)	(62)	(2,198)	334
Interest charges	13,315	18,394	51,581	56,437
Income before income taxes	47,276	58,596	390,665	402,646
Income tax expense	11,932	22,082	(39,021)	149,623
Income from continuing operations				253,023
Income from discontinued operations, net of tax ($0 and $6,841)				0
Gain on sale of discontinued operations, net of tax ($0 and $10,215)				0
Net income	35,344	36,514	429,686	253,023
Operating Segments | Pipeline and storage segment
Operating revenues
Total operating revenues	127,633	117,283	375,051	339,207
Purchased gas cost
Total purchased gas cost	561	1,251	1,906	2,331
Operation and maintenance expense	33,494	29,059	89,027	89,863
Depreciation and amortization expense	24,167	17,263	70,839	49,429
Taxes, other than income	8,200	6,098	24,181	20,579
Operating income	61,211	63,612	189,098	177,005
Miscellaneous expense	(812)	(227)	(2,093)	(784)
Interest charges	10,034	10,104	30,581	30,035
Income before income taxes	50,365	53,281	156,424	146,186
Income tax expense	14,516	18,987	21,793	52,351
Income from continuing operations				93,835
Income from discontinued operations, net of tax ($0 and $6,841)				0
Gain on sale of discontinued operations, net of tax ($0 and $10,215)				0
Net income	35,849	34,294	134,631	93,835
Intersegment eliminations
Operating revenues
Total operating revenues	(100,876)	(84,842)	(299,776)	(255,609)
Purchased gas cost
Total purchased gas cost	(100,562)	(84,842)	(298,841)	(255,565)
Operation and maintenance expense	(314)	0	(935)	(44)
Depreciation and amortization expense	0	0	0	0
Taxes, other than income	0	0	0	0
Operating income	0	0	0	0
Miscellaneous expense	0	0	0	0
Interest charges	0	0	0	0
Income before income taxes	0	0	0	0
Income tax expense	0	0	0	0
Income from continuing operations				0
Income from discontinued operations, net of tax ($0 and $6,841)				0
Gain on sale of discontinued operations, net of tax ($0 and $10,215)				0
Net income	$ 0	$ 0	$ 0	$ 0

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (PARENTHETICAL) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Income from discontinued operations, tax	$ 0	$ 6,841
Gain on sale of discontinued operations, tax	$ 0	$ 10,215

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 71,193	$ 70,808	$ 564,317	$ 360,568
Other comprehensive income (loss), net of tax
Net unrealized holding gains (losses) on available-for-sale securities, net of tax of $92, $490, $(246) and $893	310	851	(736)	1,553
Cash flow hedges:
Amortization and unrealized gain (loss) on interest rate agreements, net of tax of $2,460, $(10,667), $8,486 and $44,194	8,320	(18,556)	29,609	76,888
Net unrealized gains on commodity cash flow hedges, net of tax of $0, $0, $0 and $3,183	0	0	0	4,982
Total other comprehensive income (loss)	8,630	(17,705)	28,873	83,423
Total comprehensive income	$ 79,823	$ 53,103	$ 593,190	$ 443,991

CONDENSED CONSOLIDATED STATEME7

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (PARENTHETICAL) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net unrealized holding gains (losses) on available-for-sale securities, tax	$ 92	$ 490	$ (246)	$ 893
Amortization and unrealized gain (loss) on interest rate agreements, tax	2,460	(10,667)	8,486	44,194
Net unrealized gains on commodity cash flow hedges, tax	$ 0	$ 0	$ 0	$ 3,183

CONDENSED CONSOLIDATED STATEME8

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash Flows From Operating Activities
Net income	$ 564,317	$ 360,568
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	268,426	234,833
Deferred income taxes	139,852	188,256
One-time income tax benefit	(165,522)	0
Gain on sale of discontinued operations	0	(12,931)
Discontinued cash flow hedging for natural gas marketing commodity contracts	0	(10,579)
Other	18,007	14,892
Net assets / liabilities from risk management activities	912	25,661
Net change in operating assets and liabilities	209,304	(55,139)
Net cash provided by operating activities	1,035,296	745,561
Cash Flows From Investing Activities
Capital expenditures	(1,088,472)	(812,148)
Acquisition	0	(86,128)
Proceeds from the sale of discontinued operations	3,000	140,253
Available-for-sale securities activities, net	(7,857)	(14,329)
Use tax refund	0	18,562
Other, net	6,105	6,435
Net cash used in investing activities	(1,087,224)	(747,355)
Cash Flows From Financing Activities
Net decrease in short-term debt	(202,968)	(571,238)
Net proceeds from equity offering	395,092	98,755
Issuance of common stock through stock purchase and employee retirement plans	15,850	22,673
Proceeds from issuance of long-term debt	0	884,911
Settlement of interest rate agreements	0	(36,996)
Interest rate agreements cash collateral	0	25,670
Repayment of long-term debt	0	(250,000)
Cash dividends paid	(160,007)	(143,075)
Debt issuance costs	0	(6,663)
Other	(1,518)	0
Net cash provided by financing activities	46,449	24,037
Net increase (decrease) in cash and cash equivalents	(5,479)	22,243
Cash and cash equivalents at beginning of period	26,409	47,534
Cash and cash equivalents at end of period	$ 20,930	$ 69,777

Nature of Business

Nature of Business	9 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business Atmos Energy Corporation (“Atmos Energy” or the “Company”) is engaged in the regulated natural gas distribution and pipeline and storage businesses. Our distribution business is subject to federal and state regulation and/or regulation by local authorities in each of the states in which our regulated divisions and subsidiaries operate. Our distribution business delivers natural gas through sales and transportation arrangements to over three million residential, commercial, public authority and industrial customers through our six regulated distribution divisions, which at June 30, 2018 , covered service areas located in eight states. Our pipeline and storage business, which is also subject to federal and state regulations, includes the transportation of natural gas to our Texas and Louisiana distribution systems and the management of our underground storage facilities used to support our distribution business in various states.

Unaudited Financial Information

Unaudited Financial Information	9 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Unaudited Financial Information	Unaudited Financial Information These consolidated interim-period financial statements have been prepared in accordance with accounting principles generally accepted in the United States on the same basis as those used for the Company’s audited consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017 . In the opinion of management, all material adjustments (consisting of normal recurring accruals) necessary for a fair presentation have been made to the unaudited consolidated interim-period financial statements. These consolidated interim-period financial statements are condensed as permitted by the instructions to Form 10-Q and should be read in conjunction with the audited consolidated financial statements of Atmos Energy Corporation included in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. Because of seasonal and other factors, the results of operations for the nine -month period ended June 30, 2018 are not indicative of our results of operations for the full 2018 fiscal year, which ends September 30, 2018 . No events have occurred subsequent to the balance sheet date that would require recognition or disclosure in the condensed consolidated financial statements. Significant accounting policies Our accounting policies are described in Note 2 to the consolidated financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. During the second quarter of fiscal 2018, we completed our annual goodwill impairment assessment. Based on the assessment performed, we determined that our goodwill was not impaired. In May 2014, the Financial Accounting Standards Board (FASB) issued a comprehensive new revenue recognition standard that will supersede virtually all existing revenue recognition guidance under generally accepted accounting principles in the United States. Under the new standard, an entity will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. In doing so, companies may need to use more judgment and make more estimates than under current guidance. The new guidance will become effective for us October 1, 2018 and can be applied either retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. As of June 30, 2018, we had substantially completed the evaluation of our sources of revenue and the impact that the new guidance will have on our financial position, results of operations, cash flows and business processes. Based on this evaluation, we currently do not believe the implementation of the new guidance will have a material effect on our financial position, results of operations, cash flows or business processes. We expect to apply the new guidance using the modified retrospective method on the date of adoption. We are currently still evaluating the impact on our financial statement presentation and related disclosures. In January 2016, the FASB issued guidance related to the classification and measurement of financial instruments. The amendments modify the accounting and presentation for certain financial liabilities and equity investments not consolidated or reported using the equity method. The guidance is effective for us beginning October 1, 2018; limited early adoption is permitted. The standard will require that changes in fair value of our available-for-sale equity securities be recorded in net income. The new guidance will be applied by means of a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption. We do not anticipate the new standard will have a material impact on our financial position, results of operations or cash flows. We are currently still evaluating the impact on our financial statement presentation and related disclosures. In February 2016, the FASB issued a comprehensive new leasing standard that will require lessees to recognize a lease liability and a right-of-use asset for all leases, including operating leases, with a term greater than 12 months on its balance sheet. The new standard will be effective for us beginning on October 1, 2019; early adoption is permitted. The new leasing standard requires modified retrospective transition, which requires application of the new guidance at the beginning of the earliest comparative period presented in the year of adoption. Additionally, in January 2018, the FASB issued amendments to the standard that provides a practical expedient for entities to not evaluate existing or expired land easements that were not previously accounted for as leases under the current guidance. In July 2018, the FASB issued an amendment to the standard that provides an additional and optional transition method to adopt the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. We are currently evaluating the effect of this standard and amendments on our financial position, results of operations and cash flows. In June 2016, the FASB issued new guidance which will require credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model. Under this model, entities will estimate credit losses over the entire contractual term of the instrument from the date of initial recognition of that instrument. In contrast, current U.S. GAAP is based on an incurred loss model that delays recognition of credit losses until it is probable the loss has been incurred. The new guidance also introduces a new impairment recognition model for available-for-sale securities that will require credit losses for available-for-sale debt securities to be recorded through an allowance account. The new standard will be effective for us beginning on October 1, 2021; early adoption is permitted beginning on October 1, 2019. We are currently evaluating the potential impact of this new guidance on our financial position, results of operations and cash flows. In March 2017, the FASB issued new guidance related to the income statement presentation of the components of net periodic benefit cost for an entity’s sponsored defined benefit pension and other postretirement plans. The new guidance requires entities to disaggregate the current service cost component of the net benefit cost from the other components and present it with other current compensation costs for related employees in the statement of income. The other components of net benefit cost will be presented outside of income from operations on the statement of income. In addition, only the service cost component of net benefit cost is eligible for capitalization (e.g., as part of inventory or property, plant, and equipment). The Federal Energy Regulatory Commission (“FERC”), which regulates interstate transmission pipelines and also establishes, through its Uniform System of Accounts, accounting practices of rate-regulated entities, has issued guidance that states it will permit an election to either continue to capitalize non-service benefit costs or to cease capitalizing such costs for regulatory purposes. Accounting guidelines by the FERC are typically also followed by state commissions. As such, we plan to continue to capitalize all components of net periodic benefit cost for ratemaking purposes and will defer the non-service cost components as a regulatory asset for U.S. GAAP reporting purposes. The new guidance will be effective for us in the fiscal year beginning on October 1, 2018 and for interim periods within that year. The standard requires retrospective application of the amendment related to the presentation of non-service cost components outside of income from operations in the statement of income and prospective application of the change in eligible costs for capitalization. We do not anticipate the new standard will have a material impact on our financial position, results of operations or cash flows. In February 2018, the FASB issued new guidance as a result of the Tax Cuts and Jobs Act of 2017 (the "TCJA"), related to the treatment of certain tax effects from accumulated other comprehensive income. The new guidance allows entities to reclassify from accumulated other comprehensive income to retained earnings the stranded tax effects resulting from the adoption of the TCJA. The new guidance will be effective for us in the fiscal year beginning on October 1, 2019 and for interim periods within that year. Early adoption is permitted, including adoption in any interim period for public business entities for reporting periods for which financial statements have not yet been issued and should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Cuts and Jobs Act is recognized. We plan to early adopt the new standard effective as of September 30, 2018, and reclassify the stranded tax effects resulting from the TCJA from accumulated other comprehensive income to retained earnings. We do not anticipate the new standard will have a material impact on our financial position, results of operations or cash flows. Regulatory assets and liabilities Accounting principles generally accepted in the United States require cost-based, rate-regulated entities that meet certain criteria to reflect the authorized recovery of costs due to regulatory decisions in their financial statements. As a result, certain costs are permitted to be capitalized rather than expensed because they can be recovered through rates. We record certain costs as regulatory assets when future recovery through customer rates is considered probable. Regulatory liabilities are recorded when it is probable that revenues will be reduced for amounts that will be credited to customers through the ratemaking process. Substantially all of our regulatory assets are recorded as a component of deferred charges and other assets and a portion of our regulatory liabilities are recorded as a component of other current liabilities and deferred credits and other liabilities. Deferred gas costs are recorded either in other current assets or liabilities and our regulatory excess deferred taxes and regulatory cost of removal obligation is reported separately. Significant regulatory assets and liabilities as of June 30, 2018 and September 30, 2017 included the following: June 30, September 30, (In thousands) Regulatory assets: Pension and postretirement benefit costs (1) $ 17,546 $ 26,826 Infrastructure mechanisms (2) 77,387 46,437 Deferred gas costs 347 65,714 Recoverable loss on reacquired debt 9,328 11,208 Deferred pipeline record collection costs 16,963 11,692 APT annual adjustment mechanism — 2,160 Rate case costs 3,041 2,629 Other 5,131 10,132 $ 129,743 $ 176,798 Regulatory liabilities: Regulatory excess deferred taxes (3) $ 737,746 $ — Regulatory cost of service reserve (4) 30,930 — Regulatory cost of removal obligation 528,709 521,330 Deferred gas costs 159,201 15,559 Asset retirement obligation 12,827 12,827 APT annual adjustment mechanism 20,551 — Other 9,783 5,941 $ 1,499,747 $ 555,657 (1) Includes $7.1 million and $9.4 million of pension and postretirement expense deferred pursuant to regulatory authorization. (2) Infrastructure mechanisms in Texas and Louisiana allow for the deferral of all eligible expenses associated with capital expenditures incurred pursuant to these rules, including the recording of interest on deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recoverable through base rates. (3) The TCJA resulted in the remeasurement of the net deferred tax liability included in our rate base. Of this amount, $4.2 million is recorded in Other current liabilities. The period and timing of the return of the excess deferred taxes is being determined by regulators in each of our jurisdictions. See Note 6 for further information. (4) Effective January 1, 2018, regulators in each of our service areas required us to establish a regulatory liability for the difference in recoverable federal taxes included in revenues based on the former 35% federal statutory rate and the new 21% federal statutory rate for service provided on or after January 1, 2018. The period and timing of the return of this liability to utility customers is being determined by regulators in each of our jurisdictions. See Note 6 for further information.

Segment Information

Segment Information	9 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Segment Information	Segment Information We manage and review our consolidated operations through the following reportable segments: • The distribution segment is primarily comprised of our regulated natural gas distribution and related sales operations in eight states. • The pipeline and storage segment is comprised primarily of the pipeline and storage operations of our Atmos Pipeline-Texas division and our natural gas transmission operations in Louisiana. • The natural gas marketing segment was comprised of our discontinued natural gas marketing business. Our determination of reportable segments considers the strategic operating units under which we manage sales of various products and services to customers in differing regulatory environments. Although our distribution segment operations are geographically dispersed, they are aggregated and reported as a single segment as each natural gas distribution division has similar economic characteristics. In addition, because the pipeline and storage operations of our Atmos Pipeline-Texas division and our natural gas transmission operations in Louisiana have similar economic characteristics, they have been aggregated and reported as a single segment. The accounting policies of the segments are the same as those described in the summary of significant accounting policies found in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. We evaluate performance based on net income or loss of the respective operating units. We allocate interest and pension expense to the pipeline and storage segment; however, there is no debt or pension liability recorded on the pipeline and storage segment balance sheet. All material intercompany transactions have been eliminated; however, we have not eliminated intercompany profits when such amounts are probable of recovery under the affiliates’ rate regulation process. Income taxes are allocated to each segment as if each segment’s taxes were calculated on a separate return basis. Income statements and capital expenditures for the three and nine months ended June 30, 2018 and 2017 by segment are presented in the following tables: Three Months Ended June 30, 2018 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Operating revenues from external parties $ 534,816 $ 27,429 $ — $ 562,245 Intersegment revenues 672 100,204 (100,876 ) — Total operating revenues 535,488 127,633 (100,876 ) 562,245 Purchased gas cost 230,887 561 (100,562 ) 130,886 Operation and maintenance expense 111,895 33,494 (314 ) 145,075 Depreciation and amortization expense 66,504 24,167 — 90,671 Taxes, other than income 64,420 8,200 — 72,620 Operating income 61,782 61,211 — 122,993 Miscellaneous expense (1,191 ) (812 ) — (2,003 ) Interest charges 13,315 10,034 — 23,349 Income before income taxes 47,276 50,365 — 97,641 Income tax expense 11,932 14,516 — 26,448 Net income $ 35,344 $ 35,849 $ — $ 71,193 Capital expenditures $ 284,209 $ 110,285 $ — $ 394,494 Three Months Ended June 30, 2017 Distribution Pipeline and Storage Natural Gas Marketing Eliminations Consolidated (In thousands) Operating revenues from external parties $ 493,738 $ 32,763 $ — $ — $ 526,501 Intersegment revenues 322 84,520 — (84,842 ) — Total operating revenues 494,060 117,283 — (84,842 ) 526,501 Purchased gas cost 197,767 1,251 — (84,842 ) 114,176 Operation and maintenance expense 99,631 29,059 — — 128,690 Depreciation and amortization expense 62,760 17,263 — — 80,023 Taxes, other than income 56,850 6,098 — — 62,948 Operating income 77,052 63,612 — — 140,664 Miscellaneous expense (62 ) (227 ) — — (289 ) Interest charges 18,394 10,104 — — 28,498 Income before income taxes 58,596 53,281 — — 111,877 Income tax expense 22,082 18,987 — — 41,069 Net income $ 36,514 $ 34,294 $ — $ — $ 70,808 Capital expenditures $ 205,780 $ 46,983 $ — $ — $ 252,763 Nine Months Ended June 30, 2018 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Operating revenues from external parties $ 2,593,578 $ 77,268 $ — $ 2,670,846 Intersegment revenues 1,993 297,783 (299,776 ) — Total operating revenues 2,595,571 375,051 (299,776 ) 2,670,846 Purchased gas cost 1,421,698 1,906 (298,841 ) 1,124,763 Operation and maintenance expense 347,623 89,027 (935 ) 435,715 Depreciation and amortization expense 197,587 70,839 — 268,426 Taxes, other than income 184,219 24,181 — 208,400 Operating income 444,444 189,098 — 633,542 Miscellaneous expense (2,198 ) (2,093 ) — (4,291 ) Interest charges 51,581 30,581 — 82,162 Income before income taxes 390,665 156,424 — 547,089 Income tax (benefit) expense (39,021 ) 21,793 — (17,228 ) Net income $ 429,686 $ 134,631 $ — $ 564,317 Capital expenditures $ 749,693 $ 338,779 $ — $ 1,088,472 Nine Months Ended June 30, 2017 Distribution Pipeline and Storage Natural Gas Marketing Eliminations Consolidated (In thousands) Operating revenues from external parties $ 2,210,221 $ 84,634 $ — $ — $ 2,294,855 Intersegment revenues 1,036 254,573 — (255,609 ) — Total operating revenues 2,211,257 339,207 — (255,609 ) 2,294,855 Purchased gas cost 1,106,209 2,331 — (255,565 ) 852,975 Operation and maintenance expense 296,048 89,863 — (44 ) 385,867 Depreciation and amortization expense 185,219 49,429 — — 234,648 Taxes, other than income 165,032 20,579 — — 185,611 Operating income 458,749 177,005 — — 635,754 Miscellaneous income (expense) 334 (784 ) — — (450 ) Interest charges 56,437 30,035 — — 86,472 Income from continuing operations before income taxes 402,646 146,186 — — 548,832 Income tax expense 149,623 52,351 — — 201,974 Income from continuing operations 253,023 93,835 — — 346,858 Income from discontinued operations, net of tax — — 10,994 — 10,994 Gain on sale of discontinued operations, net of tax — — 2,716 — 2,716 Net income $ 253,023 $ 93,835 $ 13,710 $ — $ 360,568 Capital expenditures $ 636,449 $ 175,699 $ — $ — $ 812,148 Balance sheet information at June 30, 2018 and September 30, 2017 by segment is presented in the following tables: June 30, 2018 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Property, plant and equipment, net $ 7,427,486 $ 2,644,374 $ — $ 10,071,860 Total assets $ 10,840,846 $ 2,866,266 $ (2,199,488 ) $ 11,507,624 September 30, 2017 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Property, plant and equipment, net $ 6,849,517 $ 2,409,665 $ — $ 9,259,182 Total assets $ 10,050,164 $ 2,621,601 $ (1,922,169 ) $ 10,749,596

Earnings Per Share

Earnings Per Share	9 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share We use the two-class method of computing earnings per share because we have participating securities in the form of non-vested restricted stock units with a nonforfeitable right to dividend equivalents, for which vesting is predicated solely on the passage of time. The calculation of earnings per share using the two-class method excludes income attributable to these participating securities from the numerator and excludes the dilutive impact of those shares from the denominator. Basic and diluted earnings per share for the three and nine months ended June 30, 2018 and 2017 are calculated as follows: Three Months Ended Nine Months Ended 2018 2017 2018 2017 (In thousands, except per share amounts) Basic and Diluted Earnings Per Share from continuing operations Income from continuing operations $ 71,193 $ 70,808 $ 564,317 $ 346,858 Less: Income from continuing operations allocated to participating securities 59 75 545 424 Income from continuing operations available to common shareholders $ 71,134 $ 70,733 $ 563,772 $ 346,434 Basic and diluted weighted average shares outstanding 111,851 106,364 110,707 105,862 Income from continuing operations per share — Basic and Diluted $ 0.64 $ 0.67 $ 5.09 $ 3.27 Basic and Diluted Earnings Per Share from discontinued operations Income from discontinued operations $ — $ — $ — $ 13,710 Less: Income from discontinued operations allocated to participating securities — — — 15 Income from discontinued operations available to common shareholders $ — $ — $ — $ 13,695 Basic and diluted weighted average shares outstanding 111,851 106,364 110,707 105,862 Income from discontinued operations per share — Basic and Diluted $ — $ — $ — $ 0.13 Net income per share — Basic and Diluted $ 0.64 $ 0.67 $ 5.09 $ 3.40

Debt

Debt	9 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Debt	Debt The nature and terms of our debt instruments and credit facilities are described in detail in Note 5 to the consolidated financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. There were no material changes in the terms of our debt instruments during the nine months ended June 30, 2018 . Long-term debt at June 30, 2018 and September 30, 2017 consisted of the following: June 30, 2018 September 30, 2017 (In thousands) Unsecured 8.50% Senior Notes, due March 2019 $ 450,000 $ 450,000 Unsecured 3.00% Senior Notes, due 2027 500,000 500,000 Unsecured 5.95% Senior Notes, due 2034 200,000 200,000 Unsecured 5.50% Senior Notes, due 2041 400,000 400,000 Unsecured 4.15% Senior Notes, due 2043 500,000 500,000 Unsecured 4.125% Senior Notes, due 2044 750,000 750,000 Medium-term note Series A, 1995-1, 6.67%, due 2025 10,000 10,000 Unsecured 6.75% Debentures, due 2028 150,000 150,000 Floating-rate term loan, due September 2019 (1) 125,000 125,000 Total long-term debt 3,085,000 3,085,000 Less: Original issue (premium) / discount on unsecured senior notes and debentures (4,425 ) (4,384 ) Debt issuance cost 21,110 22,339 Current maturities 450,000 — $ 2,618,315 $ 3,067,045 (1) Up to $200 million can be drawn under this term loan. We utilize short-term debt to provide cost-effective, short-term financing until it can be replaced with a balance of long-term debt and equity financing that achieves the Company’s desired capital structure with an equity-to-total-capitalization ratio between 50% and 60% , inclusive of long-term and short-term debt. Our short-term borrowing requirements are affected primarily by the seasonal nature of the natural gas business. Changes in the price of natural gas and the amount of natural gas we need to supply our customers’ needs could significantly affect our borrowing requirements. Our short-term borrowings typically reach their highest levels in the winter months. Currently, our short-term borrowing requirements are satisfied through a combination of a $1.5 billion commercial paper program and three committed revolving credit facilities with third-party lenders that provide approximately $1.5 billion of total working capital funding. The primary source of our funding is our commercial paper program, which is supported by a five -year unsecured $1.5 billion credit facility. On March 26, 2018, we executed one of our two one -year extension options which extended the maturity date from September 25, 2021 to September 25, 2022 . The facility bears interest at a base rate or at a LIBOR-based rate for the applicable interest period, plus a spread ranging from zero percent to 1.25 percent , based on the Company’s credit ratings. Additionally, the facility contains a $250 million accordion feature, which provides the opportunity to increase the loan, total committed availability to $1.75 billion . At June 30, 2018 and September 30, 2017 , a total of $244.8 million and $447.7 million was outstanding under our commercial paper program. Additionally, we have a $25 million 364-day unsecured facility, which was renewed effective April 1, 2018 and expires March 31, 2019, and a $10 million 364-day unsecured revolving credit facility, which is used primarily to issue letters of credit. At June 30, 2018 , there were no borrowings outstanding under either of these facilities; however, outstanding letters of credit reduced the total amount available to us under our $10 million facility to $4.4 million . The availability of funds under these credit facilities is subject to conditions specified in the respective credit agreements, all of which we currently satisfy. These conditions include our compliance with financial covenants and the continued accuracy of representations and warranties contained in these agreements. We are required by the financial covenants in each of these facilities to maintain, at the end of each fiscal quarter, a ratio of total-debt-to-total-capitalization of no greater than 70 percent . At June 30, 2018 , our total-debt-to-total-capitalization ratio, as defined in the agreements, was 42 percent . In addition, both the interest margin and the fee that we pay on unused amounts under certain of these facilities are subject to adjustment depending upon our credit ratings. These credit facilities and our public indentures contain usual and customary covenants for our business, including covenants substantially limiting liens, substantial asset sales and mergers. Additionally, our public debt indentures relating to our senior notes and debentures, as well as certain of our revolving credit agreements, each contain a default provision that is triggered if outstanding indebtedness arising out of any other credit agreements in amounts ranging from in excess of $15 million to in excess of $100 million becomes due by acceleration or is not paid at maturity. We were in compliance with all of our debt covenants as of June 30, 2018 . If we were unable to comply with our debt covenants, we would likely be required to repay our outstanding balances on demand, provide additional collateral or take other corrective actions.

Impact of the Tax Cuts and Jobs

Impact of the Tax Cuts and Jobs Act of 2017	9 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Impact of the Tax Cuts and Jobs Act of 2017	Impact of the Tax Cuts and Jobs Act of 2017 On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the "TCJA") was signed into law. The TCJA introduced several significant changes to corporate income tax laws in the United States. The most significant change that affects Atmos Energy is the reduction of the federal statutory income tax rate from 35% to 21% . As a rate-regulated entity, the accelerated capital expensing and the limitation on interest deductibility provisions included in the TCJA are not applicable to us. Under generally accepted accounting principles, we use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. At September 30, 2017, we measured our net deferred tax liability using the enacted federal statutory tax rate of 35% . The enactment of the TCJA on December 22, 2017 required us to remeasure our deferred tax assets and liabilities, including our U.S. federal income tax net operating loss carryforwards, at the newly enacted federal statutory income tax rate. As the Company’s fiscal year end is September 30, the Internal Revenue Code requires the Company to use a blended statutory federal corporate income tax rate of 24.5% for fiscal 2018. The decrease in the federal statutory income tax rate reduced our net deferred tax liability by $903.7 million . Of this amount, $738.2 million relates to regulated operations and has been recorded as a regulatory liability, a portion of which is currently being returned to utility customers. The period and timing of these revenue adjustments are subject to Internal Revenue Code provisions and regulatory actions in each of the eight states in which we operate. During the third quarter of fiscal 2018, the Company amortized $0.5 million of this regulatory liability. The remaining $165.5 million has been reflected as a one-time income tax benefit in our condensed consolidated statement of income for the nine months ended June 30, 2018, because these taxes are not related to our cost of service ratemaking. At June 30, 2018, we had $270.7 million of remeasured federal net operating loss carryforwards. The federal net operating loss carryforwards are available to offset future taxable income and will begin to expire in 2029 . The Company also has $10.1 million of federal alternative minimum tax credit carryforwards that do not expire and are expected to be fully refunded to us between 2019 and 2022 as a result of changes introduced by the TCJA. These credit carryforwards are now reflected as taxes receivable within the deferred charges and other assets line item on our condensed consolidated balance sheet. In addition, the Company has $5.3 million in remeasured charitable contribution carryforwards to offset future taxable income. The Company’s charitable contribution carryforwards expire between 2018 and 2023 . The Company also has $21.2 million of state net operating loss carryforwards and $1.5 million of state tax credit carryforwards (net of $5.6 million and $0.4 million of remeasured federal effects). Depending on the jurisdiction in which the state net operating loss was generated, the carryforwards will begin to expire between 2018 and 2032 . Due to the changes introduced by the TCJA, we now believe it is more likely than not that the benefit from certain charitable contribution carryforwards for which a valuation allowance was previously established will be realized. As a result, we reduced our valuation allowance by $4.2 million during the first quarter. This amount is included in the $165.5 million one-time income tax benefit. The SEC issued guidance in Staff Accounting Bulletin 118 (SAB 118), which allows us to record provisional amounts during a one-year measurement period, similar to the measurement period in accounting for business combinations. The Company has determined a reasonable estimate for the measurement and accounting for certain effects of the TCJA, including the remeasurement of our net deferred tax liabilities and the establishment of a regulatory liability, which have been reflected as provisional amounts in the June 30, 2018 condensed consolidated financial statements and are described in further detail above. The amounts represent our best estimates based upon records, information and current guidance. We are still analyzing certain aspects of the TCJA, refining our calculations and expecting additional guidance relating to the TCJA from the U.S. Department of the Treasury and the Internal Revenue Service. Any additional guidance issued or future actions of our regulators could potentially affect the final determination of the accounting effects arising from the implementation of the TCJA. We are actively working with our regulators in each jurisdiction to address the impact of the TCJA on our cost of service based rates. Accounting orders were issued for all our service areas that required us to establish, effective January 1, 2018, a separate regulatory liability for the difference in taxes included in our rates that have been calculated based on a 35% statutory income tax rate and the new 21% statutory income tax rate. The establishment of this regulatory liability relating to our cost of service rates resulted in a reduction to our revenues beginning in the second quarter of fiscal 2018. The period and timing of the return of these liabilities to utility customers is being determined by regulators in each of our jurisdictions. As of June 30, 2018, this regulatory liability was $30.9 million . We have received approval from regulators to update our cost of service rates to reflect the decrease in the statutory income tax rate in our Colorado, Kansas, Kentucky, Louisiana and Texas service areas. We are still working with regulators in Mississippi, Tennessee and Virginia to reflect the effects of the lower statutory income tax rate in our cost of service in rates. During the third quarter of fiscal 2018, we received approval from regulators to return amounts to customers related to the regulatory liabilities recorded for differences in our cost of service rates due to change in the federal statutory income tax rate in Colorado and Kansas, in accordance with regulatory proceedings within one year. During the third quarter of fiscal 2018, we received approval from regulators to return amounts to customers related to the regulatory liabilities recorded for the excess deferred taxes created upon implementation of the TCJA in Colorado, Kentucky and Louisiana in accordance with regulatory proceedings on a provisional basis over periods ranging from 18 to 40 years. In our remaining jurisdictions, the treatment of the effects of the TCJA in rates is being addressed in ongoing or will be addressed in future regulatory proceedings.

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Shareholders' Equity	Shareholders' Equity Shelf Registration, At-the-Market Equity Sales Program and Equity Issuance On March 28, 2016, we filed a registration statement with the Securities and Exchange Commission (SEC) that originally permitted us to issue, from time to time, up to $2.5 billion in common stock and/or debt securities, which expires March 28, 2019. At June 30, 2018 , approximately $650 million of securities remained available for issuance under the shelf registration statement. On November 14, 2017, we filed a prospectus supplement under the registration statement relating to an at-the-market (ATM) equity sales program under which we may issue and sell shares of our common stock up to an aggregate offering price of $500 million , which expires March 28, 2019. During the nine months ended June 30, 2018 , no shares of common stock were sold under the ATM program. On November 30, 2017, we filed a prospectus supplement under the registration statement relating to an underwriting agreement to sell 4,558,404 shares of our common stock for $400 million . After expenses, net proceeds from the offering were $395.1 million . Accumulated Other Comprehensive Income (Loss) We record deferred gains (losses) in AOCI related to available-for-sale securities, interest rate cash flow hedges and prior to the sale of Atmos Energy Marketing, LLC (AEM) on January 1, 2017, commodity contract cash flow hedges. Deferred gains (losses) for our available-for-sale securities and commodity contract cash flow hedges are recognized in earnings upon settlement, while deferred gains (losses) related to our interest rate agreement cash flow hedges are recognized in earnings as they are amortized. The following tables provide the components of our accumulated other comprehensive income (loss) balances, net of the related tax effects allocated to each component of other comprehensive income (loss): Available- for-Sale Securities Interest Rate Agreement Cash Flow Hedges Total (In thousands) September 30, 2017 $ 7,048 $ (112,302 ) $ (105,254 ) Other comprehensive income before reclassifications 148 28,315 28,463 Amounts reclassified from accumulated other comprehensive income (884 ) 1,294 410 Net current-period other comprehensive income (loss) (736 ) 29,609 28,873 June 30, 2018 $ 6,312 $ (82,693 ) $ (76,381 ) Available- for-Sale Securities Interest Rate Agreement Cash Flow Hedges Commodity Contracts Cash Flow Hedges Total (In thousands) September 30, 2016 $ 4,484 $ (187,524 ) $ (4,982 ) $ (188,022 ) Other comprehensive income before reclassifications 1,485 76,602 9,847 87,934 Amounts reclassified from accumulated other comprehensive income 68 286 (4,865 ) (4,511 ) Net current-period other comprehensive income 1,553 76,888 4,982 83,423 June 30, 2017 $ 6,037 $ (110,636 ) $ — $ (104,599 ) The following tables detail reclassifications out of AOCI for the three and nine months ended June 30, 2018 and 2017 . Amounts in parentheses below indicate decreases to net income in the statement of income: Three Months Ended June 30, 2018 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Available-for-sale securities $ 7 Operation and maintenance expense 7 Total before tax (2 ) Tax expense $ 5 Net of tax Cash flow hedges Interest rate agreements $ (594 ) Interest charges (594 ) Total before tax 135 Tax benefit $ (459 ) Net of tax Total reclassifications $ (454 ) Net of tax Three Months Ended June 30, 2017 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Cash flow hedges Interest rate agreements $ (177 ) Interest charges (177 ) Total before tax 64 Tax benefit Total reclassifications $ (113 ) Net of tax Nine Months Ended June 30, 2018 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Available-for-sale securities $ 1,146 Operation and maintenance expense 1,146 Total before tax (262 ) Tax expense $ 884 Net of tax Cash flow hedges Interest rate agreements $ (1,781 ) Interest charges (1,781 ) Total before tax 487 Tax benefit $ (1,294 ) Net of tax Total reclassifications $ (410 ) Net of tax Nine Months Ended June 30, 2017 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Available-for-sale securities $ (107 ) Operation and maintenance expense (107 ) Total before tax 39 Tax benefit $ (68 ) Net of tax Cash flow hedges Interest rate agreements $ (450 ) Interest charges Commodity contracts 7,967 Purchased gas cost (1) 7,517 Total before tax (2,938 ) Tax expense $ 4,579 Net of tax Total reclassifications $ 4,511 Net of tax (1) Amount is presented as part of income from discontinued operations in the condensed consolidated statement of income.

Interim Pension and Other Postr

Interim Pension and Other Postretirement Benefit Plan Information	9 Months Ended
	Jun. 30, 2018
Retirement Benefits, Description [Abstract]
Interim Pension and Other Postretirement Benefit Plan Information	Interim Pension and Other Postretirement Benefit Plan Information The components of our net periodic pension cost for our pension and other postretirement benefit plans for the three and nine months ended June 30, 2018 and 2017 are presented in the following tables. Most of these costs are recoverable through our tariff rates. A portion of these costs is capitalized into our rate base. The remaining costs are recorded as a component of operation and maintenance expense. In the second quarter of fiscal 2018, due to the retirement of certain executives, we recognized a settlement loss of $2.4 million associated with our Supplemental Executive Retirement Plan and revalued the net periodic pension cost for the remainder of fiscal 2018. The revaluation of the net periodic pension cost for our Supplemental Executive Retirement Plan resulted in an increase in the discount rate, effective March 1, 2018, to 4.12% from 3.89% , which will increase our net periodic pension cost by approximately $0.1 million for the remainder of the fiscal year. In the third quarter of fiscal 2018, due to the retirement of one of our executives, we recognized a settlement loss of $0.9 million associated with our Supplemental Executive Retirement Plan and revalued the net periodic pension cost for the remainder of fiscal 2018. The revaluation of the net periodic pension cost for our Supplemental Executive Retirement Plan resulted in an increase in the discount rate, effective June 5, 2018, to 4.29% from 4.12% , which will increase our net periodic pension cost by approximately $0.2 million for the remainder of the fiscal year. Three Months Ended June 30 Pension Benefits Other Benefits 2018 2017 2018 2017 (In thousands) Components of net periodic pension cost: Service cost $ 4,794 $ 5,216 $ 3,020 $ 3,109 Interest cost 6,448 6,296 2,726 2,669 Expected return on assets (6,917 ) (6,993 ) (2,002 ) (1,796 ) Amortization of prior service cost (credit) (57 ) (57 ) 2 (411 ) Amortization of actuarial (gain) loss 3,050 4,248 (1,618 ) (706 ) Settlements 888 — — — Net periodic pension cost $ 8,206 $ 8,710 $ 2,128 $ 2,865 Nine Months Ended June 30 Pension Benefits Other Benefits 2018 2017 2018 2017 (In thousands) Components of net periodic pension cost: Service cost $ 13,929 $ 15,649 $ 9,059 $ 9,327 Interest cost 19,311 18,890 8,180 8,009 Expected return on assets (20,750 ) (20,981 ) (6,005 ) (5,389 ) Amortization of prior service cost (credit) (173 ) (173 ) 8 (1,233 ) Amortization of actuarial (gain) loss 9,224 12,746 (4,855 ) (2,120 ) Settlements 3,303 — — — Net periodic pension cost $ 24,844 $ 26,131 $ 6,387 $ 8,594 The assumptions used to develop our net periodic pension cost for the three and nine months ended June 30, 2018 and 2017 are as follows: Supplemental Executive Retirement Plan Pension Benefits Other Benefits 2018 2017 2018 2017 2018 2017 Discount rate 4.29% 3.73% 3.89% 3.73% 3.89% 3.73% Rate of compensation increase 3.50% 3.50% 3.50% 3.50% N/A N/A Expected return on plan assets N/A N/A 6.75% 7.00% 4.29% 4.45% The discount rate used to compute the present value of a plan’s liabilities generally is based on rates of high-grade corporate bonds with maturities similar to the average period over which the benefits will be paid. Generally, our funding policy has been to contribute annually an amount in accordance with the requirements of the Employee Retirement Income Security Act of 1974. In accordance with the Pension Protection Act of 2006 (PPA), we determined the funded status of our plan as of January 1, 2018. Based on that determination, we are not required to make a minimum contribution to our defined benefit plan during fiscal 2018 ; however, we may consider whether a voluntary contribution is prudent to maintain certain funding levels. We contributed $11.4 million to our other post-retirement benefit plans during the nine months ended June 30, 2018 . We expect to contribute a total of between $10 million and $20 million to these plans during fiscal 2018 .

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation and Environmental Matters In the normal course of business, we are subject to various legal and regulatory proceedings. For such matters, we record liabilities when they are considered probable and estimable, based on currently available facts, our historical experience, and our estimates of the ultimate outcome or resolution of the liability in the future. While the outcome of these proceedings is uncertain and a loss in excess of the amount we have accrued is possible though not reasonably estimable, it is the opinion of management that any amounts exceeding the accruals will not have a material adverse impact on our financial position, results of operations or cash flows. We maintain liability insurance for various risks associated with the operation of our natural gas pipelines and facilities, including for property damage and bodily injury. These liability insurance policies generally require us to be responsible for the first $1.0 million (self-insured retention) of each incident. The National Transportation Safety Board (NTSB) is investigating an incident that occurred at a Dallas, Texas residence on February 23, 2018 that resulted in one fatality and injuries to four other residents. Together with the Railroad Commission of Texas and the Pipeline and Hazardous Materials Safety Administration, Atmos Energy is a party to the investigation and in that capacity is working closely with the NTSB to help determine the cause of this incident. On March 29, 2018 , a civil action was filed in Dallas, Texas against Atmos Energy in response to the February 23rd incident. The plaintiffs seek over $1.0 million in damages for, among with others, wrongful death and personal injury. We are a party to various other litigation and environmental-related matters or claims that have arisen in the ordinary course of our business. While the results of such litigation and response actions to such environmental-related matters or claims cannot be predicted with certainty, we continue to believe the final outcome of such litigation and matters or claims will not have a material adverse effect on our financial condition, results of operations or cash flows. Purchase Commitments Our distribution divisions maintain supply contracts with several vendors that generally cover a period of up to one year. Commitments for estimated base gas volumes are established under these contracts on a monthly basis at contractually negotiated prices. Commitments for incremental daily purchases are made as necessary during the month in accordance with the terms of the individual contract. Our Mid-Tex Division also maintains a limited number of long-term supply contracts to ensure a reliable source of gas for our customers in its service area, which obligate it to purchase specified volumes at prices indexed to natural gas hubs. At June 30, 2018 , we were committed to purchase 53.6 Bcf within one year and 51.2 Bcf within two to three years under indexed contracts. Regulatory Matters Various regulatory agencies, including the SEC and the Commodities Futures Trading Commission, continue to adopt regulations implementing many of the provisions of the Dodd-Frank Act of 2010. We continue to enact new procedures and modify existing business practices and contractual arrangements to comply with such regulations. Additional rulemakings are pending which we believe will result in new reporting and disclosure obligations. The costs associated with hedging certain risks inherent in our business may be further increased when these expected additional regulations are adopted. As of June 30, 2018 , formula rate mechanisms were pending regulatory approval in our Louisiana, Mid-Tex, Tennessee and West Texas service areas, infrastructure mechanisms were pending regulatory approval in our Mississippi service area and rate cases were pending regulatory approval in our Mid-Tex, Virginia and West Texas service areas. These regulatory proceedings are discussed in further detail below in Management’s Discussion and Analysis — Recent Ratemaking Developments . Additionally, as discussed in further detail in Note 6, all jurisdictions are addressing impacts of the TCJA.

Financial Instruments

Financial Instruments	9 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments	Financial Instruments We currently use financial instruments to mitigate commodity price risk and interest rate risk. The objectives and strategies for using financial instruments and the related accounting for these financial instruments are fully described in Notes 2 and 13 to the consolidated financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. During the nine months ended June 30, 2018 , there were no material changes in our objectives, strategies and accounting for using financial instruments. Our financial instruments do not contain any credit-risk-related or other contingent features that could cause payments to be accelerated when our financial instruments are in net liability positions. The following summarizes those objectives and strategies. Commodity Risk Management Activities Our purchased gas cost adjustment mechanisms essentially insulate our distribution segment from commodity price risk; however, our customers are exposed to the effects of volatile natural gas prices. We manage this exposure through a combination of physical storage, fixed-price forward contracts and financial instruments, primarily over-the-counter swap and option contracts, in an effort to minimize the impact of natural gas price volatility on our customers during the winter heating season. We typically seek to hedge between 25 and 50 percent of anticipated heating season gas purchases using financial instruments. For the 2017 - 2018 heating season (generally October through March), in the jurisdictions where we are permitted to utilize financial instruments, we hedged approximately 26 percent , or 15.0 Bcf of the winter flowing gas requirements. We have not designated these financial instruments as hedges for accounting purposes. Interest Rate Risk Management Activities We periodically manage interest rate risk by entering into financial instruments to effectively fix the Treasury yield component of the interest cost associated with anticipated financings. As of June 30, 2018 , we had forward starting interest rate swaps to effectively fix the Treasury yield component associated with the anticipated issuance of $450 million unsecured senior notes in fiscal 2019 at 3.78% , which we designated as a cash flow hedge at the time the swaps were executed. As of June 30, 2018 , we had $48.7 million of net realized losses in accumulated other comprehensive income (AOCI) associated with the settlement of financial instruments used to fix the Treasury yield component of the interest cost of financing various issuances of long-term debt and senior notes, which will be recognized as a component of interest expense over the life of the associated notes from the date of settlement. The remaining amortization periods for these settled amounts extend through fiscal 2045. Quantitative Disclosures Related to Financial Instruments The following tables present detailed information concerning the impact of financial instruments on our condensed consolidated balance sheet and income statements. As of June 30, 2018 , our financial instruments were comprised of both long and short commodity positions. A long position is a contract to purchase the commodity, while a short position is a contract to sell the commodity. As of June 30, 2018 , we had 11,446 MMcf of net long commodity contracts outstanding. These contracts have not been designated as hedges. Financial Instruments on the Balance Sheet The following tables present the fair value and balance sheet classification of our financial instruments as of June 30, 2018 and September 30, 2017 . The gross amounts of recognized assets and liabilities are netted within our unaudited Condensed Consolidated Balance Sheets to the extent that we have netting arrangements with our counterparties. Balance Sheet Location Assets Liabilities (In thousands) June 30, 2018 Designated As Hedges: Interest rate contracts Other current assets / Other current liabilities $ — $ (75,763 ) Total — (75,763 ) Not Designated As Hedges: Commodity contracts Other current assets / Other current liabilities 869 (741 ) Commodity contracts Deferred charges and other assets / Deferred credits and other liabilities 108 — Total 977 (741 ) Gross Financial Instruments 977 (76,504 ) Gross Amounts Offset on Consolidated Balance Sheet: Contract netting — — Net Financial Instruments 977 (76,504 ) Cash collateral — — Net Assets/Liabilities from Risk Management Activities $ 977 $ (76,504 ) Balance Sheet Location Assets Liabilities (In thousands) September 30, 2017 Designated As Hedges: Interest rate contracts Deferred charges and other assets / Deferred credits and other liabilities $ — $ (112,076 ) Total — (112,076 ) Not Designated As Hedges: Commodity contracts Other current assets / Other current liabilities 2,436 (322 ) Commodity contracts Deferred charges and other assets / Deferred credits and other liabilities 803 — Total 3,239 (322 ) Gross Financial Instruments 3,239 (112,398 ) Gross Amounts Offset on Consolidated Balance Sheet: Contract netting — — Net Financial Instruments 3,239 (112,398 ) Cash collateral — — Net Assets/Liabilities from Risk Management Activities $ 3,239 $ (112,398 ) Impact of Financial Instruments on the Income Statement Cash Flow Hedges As discussed above, our distribution segment has interest rate swap agreements, which we designated as a cash flow hedge at the time the swaps were executed. The net loss on settled interest rate agreements reclassified from AOCI into interest charges on our condensed consolidated statements of income for the three months ended June 30, 2018 and 2017 was $0.6 million and $0.2 million and for the nine months ended June 30, 2018 and 2017 was $1.8 million and $0.5 million . The following table summarizes the gains and losses arising from hedging transactions that were recognized as a component of other comprehensive income (loss), net of taxes, for the three and nine months ended June 30, 2018 and 2017 . The amounts included in the table below exclude gains and losses arising from ineffectiveness because those amounts are immediately recognized in the income statement as incurred. Three Months Ended Nine Months Ended 2018 2017 (1) 2018 2017 (1) (In thousands) Increase (decrease) in fair value: Interest rate agreements $ 7,861 $ (18,669 ) $ 28,315 $ 76,602 Forward commodity contracts (2) — — — 9,847 Recognition of (gains) losses in earnings due to settlements: Interest rate agreements 459 113 1,294 286 Forward commodity contracts (2) — — — (4,865 ) Total other comprehensive income (loss) from hedging, net of tax $ 8,320 $ (18,556 ) $ 29,609 $ 81,870 (1) Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction for the three and nine-month periods ended June 30, 2017. (2) Due to the sale of AEM, these amounts are included in income from discontinued operations. Deferred gains (losses) recorded in AOCI associated with our interest rate agreements are recognized in earnings as they are amortized over the terms of the underlying debt instruments. The following amounts, net of deferred taxes, represent the expected recognition in earnings, as of June 30, 2018 , of the deferred losses recorded in AOCI associated with our financial instruments, based upon the fair values of these financial instruments at the date of settlement. However, the table below does not include the expected recognition in earnings of our outstanding interest rate agreements as those instruments have not yet settled. Interest Rate Agreements (In thousands) Next twelve months $ (1,848 ) Thereafter (46,808 ) Total $ (48,656 ) Financial Instruments Not Designated as Hedges As discussed above, financial instruments used in our distribution segment are not designated as hedges. However, there is no earnings impact on our distribution segment as a result of the use of these financial instruments because the gains and losses arising from the use of these financial instruments are recognized in the consolidated statement of income as a component of purchased gas cost when the related costs are recovered through our rates and recognized in revenue. Accordingly, the impact of these financial instruments is excluded from this presentation.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We report certain assets and liabilities at fair value, which is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). We record cash and cash equivalents, accounts receivable and accounts payable at carrying value, which substantially approximates fair value due to the short-term nature of these assets and liabilities. For other financial assets and liabilities, we primarily use quoted market prices and other observable market pricing information to minimize the use of unobservable pricing inputs in our measurements when determining fair value. The methods used to determine fair value for our assets and liabilities are fully described in Note 2 to the financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. During the nine months ended June 30, 2018 , there were no changes in these methods. Fair value measurements also apply to the valuation of our pension and postretirement plan assets. Current accounting guidance requires employers to annually disclose information about fair value measurements of the assets of a defined benefit pension or other postretirement plan. The fair value of these assets is presented in Note 7 to the financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. Quantitative Disclosures Financial Instruments The classification of our fair value measurements requires judgment regarding the degree to which market data is observable or corroborated by observable market data. Authoritative accounting literature establishes a fair value hierarchy that prioritizes the inputs used to measure fair value based on observable and unobservable data. The hierarchy categorizes the inputs into three levels, with the highest priority given to unadjusted quoted prices in active markets for identical assets and liabilities (Level 1), with the lowest priority given to unobservable inputs (Level 3). The following tables summarize, by level within the fair value hierarchy, our assets and liabilities that were accounted for at fair value on a recurring basis as of June 30, 2018 and September 30, 2017 . Assets and liabilities are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement. Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) (1) Significant Other Unobservable Inputs (Level 3) Netting and Cash Collateral June 30, 2018 (In thousands) Assets: Financial instruments $ — $ 977 $ — $ — $ 977 Available-for-sale securities Registered investment companies 43,548 — — — 43,548 Bond mutual funds 21,378 — — — 21,378 Bonds — 30,303 — — 30,303 Money market funds — 2,195 — — 2,195 Total available-for-sale securities 64,926 32,498 — — 97,424 Total assets $ 64,926 $ 33,475 $ — $ — $ 98,401 Liabilities: Financial instruments $ — $ 76,504 $ — $ — $ 76,504 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) (1) Significant Other Unobservable Inputs (Level 3) Netting and Cash Collateral September 30, 2017 (In thousands) Assets: Financial instruments $ — $ 3,239 $ — $ — $ 3,239 Available-for-sale securities Registered investment companies 41,097 — — — 41,097 Bond mutual funds 16,371 — — — 16,371 Bonds — 29,104 — — 29,104 Money market funds — 1,837 — — 1,837 Total available-for-sale securities 57,468 30,941 — — 88,409 Total assets $ 57,468 $ 34,180 $ — $ — $ 91,648 Liabilities: Financial instruments $ — $ 112,398 $ — $ — $ 112,398 (1) Our Level 2 measurements consist of over-the-counter options and swaps, which are valued using a market-based approach in which observable market prices are adjusted for criteria specific to each instrument, such as the strike price, notional amount or basis differences, municipal and corporate bonds, which are valued based on the most recent available quoted market prices and money market funds that are valued at cost. Available-for-sale securities are comprised of the following: Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value (In thousands) As of June 30, 2018 Domestic equity mutual funds $ 28,283 $ 8,973 $ (293 ) $ 36,963 Foreign equity mutual funds 4,656 1,929 — 6,585 Bond mutual funds 21,673 — (295 ) 21,378 Bonds 30,434 8 (139 ) 30,303 Money market funds 2,195 — — 2,195 $ 87,241 $ 10,910 $ (727 ) $ 97,424 As of September 30, 2017 Domestic equity mutual funds $ 25,361 $ 8,920 $ — $ 34,281 Foreign equity mutual funds 4,581 2,235 — 6,816 Bond mutual funds 16,391 2 (22 ) 16,371 Bonds 29,074 46 (16 ) 29,104 Money market funds 1,837 — — 1,837 $ 77,244 $ 11,203 $ (38 ) $ 88,409 At June 30, 2018 and September 30, 2017 , our available-for-sale securities included $45.7 million and $42.9 million related to assets held in separate rabbi trusts for our supplemental executive benefit plans. At June 30, 2018 , we maintained investments in bonds that have contractual maturity dates ranging from July 2018 through June 2021. These securities are reported at market value with unrealized gains and losses shown as a component of accumulated other comprehensive income (loss). We regularly evaluate the performance of these investments on a fund by fund basis for impairment, taking into consideration the fund’s purpose, volatility and current returns. If a determination is made that a decline in fair value is other than temporary, the related fund is written down to its estimated fair value and the other-than-temporary impairment is recognized in the income statement. Other Fair Value Measures Our debt is recorded at carrying value. The fair value of our debt is determined using third party market value quotations, which are considered Level 1 fair value measurements for debt instruments with a recent, observable trade or Level 2 fair value measurements for debt instruments where fair value is determined using the most recent available quoted market price. The following table presents the carrying value and fair value of our debt as of June 30, 2018 and September 30, 2017 : June 30, 2018 September 30, 2017 (In thousands) Carrying Amount $ 3,085,000 $ 3,085,000 Fair Value $ 3,216,893 $ 3,382,272

Concentration of Credit Risk

Concentration of Credit Risk	9 Months Ended
	Jun. 30, 2018
Risks and Uncertainties [Abstract]
Concentration of Credit Risk	Concentration of Credit Risk Information regarding our concentration of credit risk is disclosed in Note 16 to the financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. During the nine months ended June 30, 2018 , there were no material changes in our concentration of credit risk.

Discontinued Operations

Discontinued Operations	9 Months Ended
	Jun. 30, 2018
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations On October 29, 2016, we entered into a Membership Interest Purchase Agreement (the Agreement) with CenterPoint Energy Services, Inc., a subsidiary of CenterPoint Energy, Inc. (CES) to sell all of the equity interests of Atmos Energy Marketing, LLC (AEM). The transaction closed on January 3, 2017, with an effective date of January 1, 2017 . CES paid a cash purchase price of $38.3 million plus working capital of $109.0 million for total cash consideration of $147.3 million . Of this amount, $7.0 million was placed into escrow and was to be paid to the Company within 24 months of the closing date, net of any indemnification claims agreed upon between the two companies. In January 2018, $3.0 million of this escrowed amount was released and received by the Company. We recognized a net gain of $0.03 per diluted share on the sale in the second quarter of fiscal 2017 and completed the working capital true–up during the third quarter of fiscal 2017. The operating results of our natural gas marketing reportable segment have been reported on the condensed consolidated statement of income as income from discontinued operations, net of income tax, for the nine months ended June 30, 2017. Accordingly, expenses related to allocable general corporate overhead and interest expense are not included in these results. The tables below set forth selected financial information related to discontinued operations. Operating expenses include operation and maintenance expense, provision for doubtful accounts, depreciation and amortization expense and taxes, other than income. At June 30, 2018 and September 30, 2017 we did not have any assets or liabilities held for sale. The following table presents statement of income data related to discontinued operations: Nine Months Ended (In thousands) Operating revenues $ 303,474 Purchased gas cost 277,554 Operating expenses 7,874 Operating income 18,046 Other nonoperating expense (211 ) Income from discontinued operations before income taxes 17,835 Income tax expense 6,841 Income from discontinued operations 10,994 Gain on sale from discontinued operations, net of tax ($10,215) 2,716 Net income from discontinued operations $ 13,710 The following table presents statement of cash flow data related to discontinued operations: Nine Months Ended (In thousands) Depreciation and amortization expense $ 185 Capital expenditures $ — Non-cash loss in commodity contract cash flow hedges $ (8,165 ) Natural Gas Marketing Commodity Risk Management Activities Our discontinued natural gas marketing segment was exposed to risks associated with changes in the market price of natural gas through the purchase, sale and delivery of natural gas to its customers at competitive prices. Through December 31, 2016, we managed our exposure to such risks through a combination of physical storage and financial instruments, including futures, over-the-counter and exchange-traded options and swap contracts with counterparties. Effective January 1, 2017, as a result of the sale of AEM, these activities were discontinued. Due to the sale of AEM, we determined that the cash flows associated with our natural gas marketing commodity cash flow hedges were no longer probable of occurring; therefore, we discontinued hedge accounting as of December 31, 2016. As a result, we reclassified the gain in accumulated other comprehensive income associated with the commodity contracts into earnings as a reduction of purchased gas cost and recognized a pre-tax gain of $10.6 million , which is included in income from discontinued operations on the condensed consolidated statement of income for the nine months ended June 30, 2017. The Company's other risk management activities are discussed in Note 10. Impact of Financial Instruments on the Income Statement Hedge ineffectiveness for our natural gas marketing segment was recorded as a component of purchased gas cost, which is included in discontinued operations on the condensed consolidated statements of income, and primarily results from differences in the location and timing of the derivative instrument and the hedged item. For the nine months ended June 30, 2017 , we recognized a gain arising from fair value and cash flow hedge ineffectiveness of $3.4 million . Additional information regarding ineffectiveness recognized in the income statement is included in the tables below. Fair Value Hedges The impact of our natural gas marketing segment commodity contracts designated as fair value hedges and the related hedged item on the results of discontinued operations on our condensed consolidated income statement for the nine months ended June 30, 2017 is presented below. Nine Months Ended (In thousands) Commodity contracts $ (9,567 ) Fair value adjustment for natural gas inventory designated as the hedged item 12,858 Total decrease in purchased gas cost reflected in income from discontinued operations $ 3,291 The decrease in purchased gas cost reflected in income from discontinued operations is comprised of the following: Basis ineffectiveness $ (597 ) Timing ineffectiveness 3,888 $ 3,291 Basis ineffectiveness arises from natural gas market price differences between the locations of the hedged inventory and the delivery location specified in the hedge instruments. Timing ineffectiveness arises due to changes in the difference between the spot price and the futures price, as well as the difference between the timing of the settlement of the futures and the valuation of the underlying physical commodity. Cash Flow Hedges The impact of our natural gas marketing segment cash flow hedges on our condensed consolidated income statements for the nine months ended June 30, 2017 is presented below: Nine Months Ended (In thousands) Loss reclassified from AOCI for effective portion of natural gas marketing commodity contracts $ (2,612 ) Gain arising from ineffective portion of natural gas marketing commodity contracts 111 Gain on discontinuance of cash flow hedging of natural gas marketing commodity contracts reclassified from AOCI 10,579 Total impact on purchased gas cost reflected in income from discontinued operations $ 8,078 Financial Instruments Not Designated as Hedges The impact of the natural gas marketing segment's financial instruments that had not been designated as hedges on our condensed consolidated income statements for the nine months ended June 30, 2017 was a decrease in purchased gas cost of $6.8 million , which is included in discontinued operations on the condensed consolidated statements of income.

Unaudited Financial Informati22

Unaudited Financial Information (Policies)	9 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Significant accounting policies	Significant accounting policies Our accounting policies are described in Note 2 to the consolidated financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. During the second quarter of fiscal 2018, we completed our annual goodwill impairment assessment. Based on the assessment performed, we determined that our goodwill was not impaired. In May 2014, the Financial Accounting Standards Board (FASB) issued a comprehensive new revenue recognition standard that will supersede virtually all existing revenue recognition guidance under generally accepted accounting principles in the United States. Under the new standard, an entity will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. In doing so, companies may need to use more judgment and make more estimates than under current guidance. The new guidance will become effective for us October 1, 2018 and can be applied either retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. As of June 30, 2018, we had substantially completed the evaluation of our sources of revenue and the impact that the new guidance will have on our financial position, results of operations, cash flows and business processes. Based on this evaluation, we currently do not believe the implementation of the new guidance will have a material effect on our financial position, results of operations, cash flows or business processes. We expect to apply the new guidance using the modified retrospective method on the date of adoption. We are currently still evaluating the impact on our financial statement presentation and related disclosures. In January 2016, the FASB issued guidance related to the classification and measurement of financial instruments. The amendments modify the accounting and presentation for certain financial liabilities and equity investments not consolidated or reported using the equity method. The guidance is effective for us beginning October 1, 2018; limited early adoption is permitted. The standard will require that changes in fair value of our available-for-sale equity securities be recorded in net income. The new guidance will be applied by means of a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption. We do not anticipate the new standard will have a material impact on our financial position, results of operations or cash flows. We are currently still evaluating the impact on our financial statement presentation and related disclosures. In February 2016, the FASB issued a comprehensive new leasing standard that will require lessees to recognize a lease liability and a right-of-use asset for all leases, including operating leases, with a term greater than 12 months on its balance sheet. The new standard will be effective for us beginning on October 1, 2019; early adoption is permitted. The new leasing standard requires modified retrospective transition, which requires application of the new guidance at the beginning of the earliest comparative period presented in the year of adoption. Additionally, in January 2018, the FASB issued amendments to the standard that provides a practical expedient for entities to not evaluate existing or expired land easements that were not previously accounted for as leases under the current guidance. In July 2018, the FASB issued an amendment to the standard that provides an additional and optional transition method to adopt the standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. We are currently evaluating the effect of this standard and amendments on our financial position, results of operations and cash flows. In June 2016, the FASB issued new guidance which will require credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model. Under this model, entities will estimate credit losses over the entire contractual term of the instrument from the date of initial recognition of that instrument. In contrast, current U.S. GAAP is based on an incurred loss model that delays recognition of credit losses until it is probable the loss has been incurred. The new guidance also introduces a new impairment recognition model for available-for-sale securities that will require credit losses for available-for-sale debt securities to be recorded through an allowance account. The new standard will be effective for us beginning on October 1, 2021; early adoption is permitted beginning on October 1, 2019. We are currently evaluating the potential impact of this new guidance on our financial position, results of operations and cash flows. In March 2017, the FASB issued new guidance related to the income statement presentation of the components of net periodic benefit cost for an entity’s sponsored defined benefit pension and other postretirement plans. The new guidance requires entities to disaggregate the current service cost component of the net benefit cost from the other components and present it with other current compensation costs for related employees in the statement of income. The other components of net benefit cost will be presented outside of income from operations on the statement of income. In addition, only the service cost component of net benefit cost is eligible for capitalization (e.g., as part of inventory or property, plant, and equipment). The Federal Energy Regulatory Commission (“FERC”), which regulates interstate transmission pipelines and also establishes, through its Uniform System of Accounts, accounting practices of rate-regulated entities, has issued guidance that states it will permit an election to either continue to capitalize non-service benefit costs or to cease capitalizing such costs for regulatory purposes. Accounting guidelines by the FERC are typically also followed by state commissions. As such, we plan to continue to capitalize all components of net periodic benefit cost for ratemaking purposes and will defer the non-service cost components as a regulatory asset for U.S. GAAP reporting purposes. The new guidance will be effective for us in the fiscal year beginning on October 1, 2018 and for interim periods within that year. The standard requires retrospective application of the amendment related to the presentation of non-service cost components outside of income from operations in the statement of income and prospective application of the change in eligible costs for capitalization. We do not anticipate the new standard will have a material impact on our financial position, results of operations or cash flows. In February 2018, the FASB issued new guidance as a result of the Tax Cuts and Jobs Act of 2017 (the "TCJA"), related to the treatment of certain tax effects from accumulated other comprehensive income. The new guidance allows entities to reclassify from accumulated other comprehensive income to retained earnings the stranded tax effects resulting from the adoption of the TCJA. The new guidance will be effective for us in the fiscal year beginning on October 1, 2019 and for interim periods within that year. Early adoption is permitted, including adoption in any interim period for public business entities for reporting periods for which financial statements have not yet been issued and should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Cuts and Jobs Act is recognized. We plan to early adopt the new standard effective as of September 30, 2018, and reclassify the stranded tax effects resulting from the TCJA from accumulated other comprehensive income to retained earnings. We do not anticipate the new standard will have a material impact on our financial position, results of operations or cash flows.
Regulatory assets and liabilities	Regulatory assets and liabilities Accounting principles generally accepted in the United States require cost-based, rate-regulated entities that meet certain criteria to reflect the authorized recovery of costs due to regulatory decisions in their financial statements. As a result, certain costs are permitted to be capitalized rather than expensed because they can be recovered through rates. We record certain costs as regulatory assets when future recovery through customer rates is considered probable. Regulatory liabilities are recorded when it is probable that revenues will be reduced for amounts that will be credited to customers through the ratemaking process. Substantially all of our regulatory assets are recorded as a component of deferred charges and other assets and a portion of our regulatory liabilities are recorded as a component of other current liabilities and deferred credits and other liabilities. Deferred gas costs are recorded either in other current assets or liabilities and our regulatory excess deferred taxes and regulatory cost of removal obligation is reported separately.
Segment Reporting	The accounting policies of the segments are the same as those described in the summary of significant accounting policies found in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017. We evaluate performance based on net income or loss of the respective operating units. We allocate interest and pension expense to the pipeline and storage segment; however, there is no debt or pension liability recorded on the pipeline and storage segment balance sheet. All material intercompany transactions have been eliminated; however, we have not eliminated intercompany profits when such amounts are probable of recovery under the affiliates’ rate regulation process. Income taxes are allocated to each segment as if each segment’s taxes were calculated on a separate return basis.
Earnings Per Share	Earnings Per Share We use the two-class method of computing earnings per share because we have participating securities in the form of non-vested restricted stock units with a nonforfeitable right to dividend equivalents, for which vesting is predicated solely on the passage of time. The calculation of earnings per share using the two-class method excludes income attributable to these participating securities from the numerator and excludes the dilutive impact of those shares from the denominator.
Fair Value Measurements	Fair Value Measurements We report certain assets and liabilities at fair value, which is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). We record cash and cash equivalents, accounts receivable and accounts payable at carrying value, which substantially approximates fair value due to the short-term nature of these assets and liabilities. For other financial assets and liabilities, we primarily use quoted market prices and other observable market pricing information to minimize the use of unobservable pricing inputs in our measurements when determining fair value. The methods used to determine fair value for our assets and liabilities are fully described in Note 2 to the financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2017.
Income Tax	Under generally accepted accounting principles, we use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled.

Unaudited Financial Informati23

Unaudited Financial Information (Table)	9 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Schedule of Regulatory Assets	Significant regulatory assets and liabilities as of June 30, 2018 and September 30, 2017 included the following: June 30, September 30, (In thousands) Regulatory assets: Pension and postretirement benefit costs (1) $ 17,546 $ 26,826 Infrastructure mechanisms (2) 77,387 46,437 Deferred gas costs 347 65,714 Recoverable loss on reacquired debt 9,328 11,208 Deferred pipeline record collection costs 16,963 11,692 APT annual adjustment mechanism — 2,160 Rate case costs 3,041 2,629 Other 5,131 10,132 $ 129,743 $ 176,798 Regulatory liabilities: Regulatory excess deferred taxes (3) $ 737,746 $ — Regulatory cost of service reserve (4) 30,930 — Regulatory cost of removal obligation 528,709 521,330 Deferred gas costs 159,201 15,559 Asset retirement obligation 12,827 12,827 APT annual adjustment mechanism 20,551 — Other 9,783 5,941 $ 1,499,747 $ 555,657 (1) Includes $7.1 million and $9.4 million of pension and postretirement expense deferred pursuant to regulatory authorization. (2) Infrastructure mechanisms in Texas and Louisiana allow for the deferral of all eligible expenses associated with capital expenditures incurred pursuant to these rules, including the recording of interest on deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recoverable through base rates. (3) The TCJA resulted in the remeasurement of the net deferred tax liability included in our rate base. Of this amount, $4.2 million is recorded in Other current liabilities. The period and timing of the return of the excess deferred taxes is being determined by regulators in each of our jurisdictions. See Note 6 for further information. (4) Effective January 1, 2018, regulators in each of our service areas required us to establish a regulatory liability for the difference in recoverable federal taxes included in revenues based on the former 35% federal statutory rate and the new 21% federal statutory rate for service provided on or after January 1, 2018. The period and timing of the return of this liability to utility customers is being determined by regulators in each of our jurisdictions. See Note 6 for further information.
Schedule of Regulatory Liabilities	Significant regulatory assets and liabilities as of June 30, 2018 and September 30, 2017 included the following: June 30, September 30, (In thousands) Regulatory assets: Pension and postretirement benefit costs (1) $ 17,546 $ 26,826 Infrastructure mechanisms (2) 77,387 46,437 Deferred gas costs 347 65,714 Recoverable loss on reacquired debt 9,328 11,208 Deferred pipeline record collection costs 16,963 11,692 APT annual adjustment mechanism — 2,160 Rate case costs 3,041 2,629 Other 5,131 10,132 $ 129,743 $ 176,798 Regulatory liabilities: Regulatory excess deferred taxes (3) $ 737,746 $ — Regulatory cost of service reserve (4) 30,930 — Regulatory cost of removal obligation 528,709 521,330 Deferred gas costs 159,201 15,559 Asset retirement obligation 12,827 12,827 APT annual adjustment mechanism 20,551 — Other 9,783 5,941 $ 1,499,747 $ 555,657 (1) Includes $7.1 million and $9.4 million of pension and postretirement expense deferred pursuant to regulatory authorization. (2) Infrastructure mechanisms in Texas and Louisiana allow for the deferral of all eligible expenses associated with capital expenditures incurred pursuant to these rules, including the recording of interest on deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recoverable through base rates. (3) The TCJA resulted in the remeasurement of the net deferred tax liability included in our rate base. Of this amount, $4.2 million is recorded in Other current liabilities. The period and timing of the return of the excess deferred taxes is being determined by regulators in each of our jurisdictions. See Note 6 for further information. (4) Effective January 1, 2018, regulators in each of our service areas required us to establish a regulatory liability for the difference in recoverable federal taxes included in revenues based on the former 35% federal statutory rate and the new 21% federal statutory rate for service provided on or after January 1, 2018. The period and timing of the return of this liability to utility customers is being determined by regulators in each of our jurisdictions. See Note 6 for further information.

Segment Information (Table)

Segment Information (Table)	9 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Income statements and capital expenditures for the three and nine months ended June 30, 2018 and 2017 by segment are presented in the following tables: Three Months Ended June 30, 2018 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Operating revenues from external parties $ 534,816 $ 27,429 $ — $ 562,245 Intersegment revenues 672 100,204 (100,876 ) — Total operating revenues 535,488 127,633 (100,876 ) 562,245 Purchased gas cost 230,887 561 (100,562 ) 130,886 Operation and maintenance expense 111,895 33,494 (314 ) 145,075 Depreciation and amortization expense 66,504 24,167 — 90,671 Taxes, other than income 64,420 8,200 — 72,620 Operating income 61,782 61,211 — 122,993 Miscellaneous expense (1,191 ) (812 ) — (2,003 ) Interest charges 13,315 10,034 — 23,349 Income before income taxes 47,276 50,365 — 97,641 Income tax expense 11,932 14,516 — 26,448 Net income $ 35,344 $ 35,849 $ — $ 71,193 Capital expenditures $ 284,209 $ 110,285 $ — $ 394,494 Three Months Ended June 30, 2017 Distribution Pipeline and Storage Natural Gas Marketing Eliminations Consolidated (In thousands) Operating revenues from external parties $ 493,738 $ 32,763 $ — $ — $ 526,501 Intersegment revenues 322 84,520 — (84,842 ) — Total operating revenues 494,060 117,283 — (84,842 ) 526,501 Purchased gas cost 197,767 1,251 — (84,842 ) 114,176 Operation and maintenance expense 99,631 29,059 — — 128,690 Depreciation and amortization expense 62,760 17,263 — — 80,023 Taxes, other than income 56,850 6,098 — — 62,948 Operating income 77,052 63,612 — — 140,664 Miscellaneous expense (62 ) (227 ) — — (289 ) Interest charges 18,394 10,104 — — 28,498 Income before income taxes 58,596 53,281 — — 111,877 Income tax expense 22,082 18,987 — — 41,069 Net income $ 36,514 $ 34,294 $ — $ — $ 70,808 Capital expenditures $ 205,780 $ 46,983 $ — $ — $ 252,763 Nine Months Ended June 30, 2018 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Operating revenues from external parties $ 2,593,578 $ 77,268 $ — $ 2,670,846 Intersegment revenues 1,993 297,783 (299,776 ) — Total operating revenues 2,595,571 375,051 (299,776 ) 2,670,846 Purchased gas cost 1,421,698 1,906 (298,841 ) 1,124,763 Operation and maintenance expense 347,623 89,027 (935 ) 435,715 Depreciation and amortization expense 197,587 70,839 — 268,426 Taxes, other than income 184,219 24,181 — 208,400 Operating income 444,444 189,098 — 633,542 Miscellaneous expense (2,198 ) (2,093 ) — (4,291 ) Interest charges 51,581 30,581 — 82,162 Income before income taxes 390,665 156,424 — 547,089 Income tax (benefit) expense (39,021 ) 21,793 — (17,228 ) Net income $ 429,686 $ 134,631 $ — $ 564,317 Capital expenditures $ 749,693 $ 338,779 $ — $ 1,088,472 Nine Months Ended June 30, 2017 Distribution Pipeline and Storage Natural Gas Marketing Eliminations Consolidated (In thousands) Operating revenues from external parties $ 2,210,221 $ 84,634 $ — $ — $ 2,294,855 Intersegment revenues 1,036 254,573 — (255,609 ) — Total operating revenues 2,211,257 339,207 — (255,609 ) 2,294,855 Purchased gas cost 1,106,209 2,331 — (255,565 ) 852,975 Operation and maintenance expense 296,048 89,863 — (44 ) 385,867 Depreciation and amortization expense 185,219 49,429 — — 234,648 Taxes, other than income 165,032 20,579 — — 185,611 Operating income 458,749 177,005 — — 635,754 Miscellaneous income (expense) 334 (784 ) — — (450 ) Interest charges 56,437 30,035 — — 86,472 Income from continuing operations before income taxes 402,646 146,186 — — 548,832 Income tax expense 149,623 52,351 — — 201,974 Income from continuing operations 253,023 93,835 — — 346,858 Income from discontinued operations, net of tax — — 10,994 — 10,994 Gain on sale of discontinued operations, net of tax — — 2,716 — 2,716 Net income $ 253,023 $ 93,835 $ 13,710 $ — $ 360,568 Capital expenditures $ 636,449 $ 175,699 $ — $ — $ 812,148 Balance sheet information at June 30, 2018 and September 30, 2017 by segment is presented in the following tables: June 30, 2018 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Property, plant and equipment, net $ 7,427,486 $ 2,644,374 $ — $ 10,071,860 Total assets $ 10,840,846 $ 2,866,266 $ (2,199,488 ) $ 11,507,624 September 30, 2017 Distribution Pipeline and Storage Eliminations Consolidated (In thousands) Property, plant and equipment, net $ 6,849,517 $ 2,409,665 $ — $ 9,259,182 Total assets $ 10,050,164 $ 2,621,601 $ (1,922,169 ) $ 10,749,596

Earnings Per Share (Table)

Earnings Per Share (Table)	9 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Basic and diluted earnings per share for the three and nine months ended June 30, 2018 and 2017 are calculated as follows: Three Months Ended Nine Months Ended 2018 2017 2018 2017 (In thousands, except per share amounts) Basic and Diluted Earnings Per Share from continuing operations Income from continuing operations $ 71,193 $ 70,808 $ 564,317 $ 346,858 Less: Income from continuing operations allocated to participating securities 59 75 545 424 Income from continuing operations available to common shareholders $ 71,134 $ 70,733 $ 563,772 $ 346,434 Basic and diluted weighted average shares outstanding 111,851 106,364 110,707 105,862 Income from continuing operations per share — Basic and Diluted $ 0.64 $ 0.67 $ 5.09 $ 3.27 Basic and Diluted Earnings Per Share from discontinued operations Income from discontinued operations $ — $ — $ — $ 13,710 Less: Income from discontinued operations allocated to participating securities — — — 15 Income from discontinued operations available to common shareholders $ — $ — $ — $ 13,695 Basic and diluted weighted average shares outstanding 111,851 106,364 110,707 105,862 Income from discontinued operations per share — Basic and Diluted $ — $ — $ — $ 0.13 Net income per share — Basic and Diluted $ 0.64 $ 0.67 $ 5.09 $ 3.40

Debt (Table)

Debt (Table)	9 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long-term debt at June 30, 2018 and September 30, 2017 consisted of the following: June 30, 2018 September 30, 2017 (In thousands) Unsecured 8.50% Senior Notes, due March 2019 $ 450,000 $ 450,000 Unsecured 3.00% Senior Notes, due 2027 500,000 500,000 Unsecured 5.95% Senior Notes, due 2034 200,000 200,000 Unsecured 5.50% Senior Notes, due 2041 400,000 400,000 Unsecured 4.15% Senior Notes, due 2043 500,000 500,000 Unsecured 4.125% Senior Notes, due 2044 750,000 750,000 Medium-term note Series A, 1995-1, 6.67%, due 2025 10,000 10,000 Unsecured 6.75% Debentures, due 2028 150,000 150,000 Floating-rate term loan, due September 2019 (1) 125,000 125,000 Total long-term debt 3,085,000 3,085,000 Less: Original issue (premium) / discount on unsecured senior notes and debentures (4,425 ) (4,384 ) Debt issuance cost 21,110 22,339 Current maturities 450,000 — $ 2,618,315 $ 3,067,045 (1) Up to $200 million can be drawn under this term loan.

Shareholders' Equity (Table)

Shareholders' Equity (Table)	9 Months Ended
	Jun. 30, 2018
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following tables provide the components of our accumulated other comprehensive income (loss) balances, net of the related tax effects allocated to each component of other comprehensive income (loss): Available- for-Sale Securities Interest Rate Agreement Cash Flow Hedges Total (In thousands) September 30, 2017 $ 7,048 $ (112,302 ) $ (105,254 ) Other comprehensive income before reclassifications 148 28,315 28,463 Amounts reclassified from accumulated other comprehensive income (884 ) 1,294 410 Net current-period other comprehensive income (loss) (736 ) 29,609 28,873 June 30, 2018 $ 6,312 $ (82,693 ) $ (76,381 ) Available- for-Sale Securities Interest Rate Agreement Cash Flow Hedges Commodity Contracts Cash Flow Hedges Total (In thousands) September 30, 2016 $ 4,484 $ (187,524 ) $ (4,982 ) $ (188,022 ) Other comprehensive income before reclassifications 1,485 76,602 9,847 87,934 Amounts reclassified from accumulated other comprehensive income 68 286 (4,865 ) (4,511 ) Net current-period other comprehensive income 1,553 76,888 4,982 83,423 June 30, 2017 $ 6,037 $ (110,636 ) $ — $ (104,599 )
Reclassification out of Accumulated Other Comprehensive Income	The following tables detail reclassifications out of AOCI for the three and nine months ended June 30, 2018 and 2017 . Amounts in parentheses below indicate decreases to net income in the statement of income: Three Months Ended June 30, 2018 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Available-for-sale securities $ 7 Operation and maintenance expense 7 Total before tax (2 ) Tax expense $ 5 Net of tax Cash flow hedges Interest rate agreements $ (594 ) Interest charges (594 ) Total before tax 135 Tax benefit $ (459 ) Net of tax Total reclassifications $ (454 ) Net of tax Three Months Ended June 30, 2017 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Cash flow hedges Interest rate agreements $ (177 ) Interest charges (177 ) Total before tax 64 Tax benefit Total reclassifications $ (113 ) Net of tax Nine Months Ended June 30, 2018 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Available-for-sale securities $ 1,146 Operation and maintenance expense 1,146 Total before tax (262 ) Tax expense $ 884 Net of tax Cash flow hedges Interest rate agreements $ (1,781 ) Interest charges (1,781 ) Total before tax 487 Tax benefit $ (1,294 ) Net of tax Total reclassifications $ (410 ) Net of tax Nine Months Ended June 30, 2017 Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (In thousands) Available-for-sale securities $ (107 ) Operation and maintenance expense (107 ) Total before tax 39 Tax benefit $ (68 ) Net of tax Cash flow hedges Interest rate agreements $ (450 ) Interest charges Commodity contracts 7,967 Purchased gas cost (1) 7,517 Total before tax (2,938 ) Tax expense $ 4,579 Net of tax Total reclassifications $ 4,511 Net of tax (1) Amount is presented as part of income from discontinued operations in the condensed consolidated statement of income.

Interim Pension and Other Pos28

Interim Pension and Other Postretirement Benefit Plan Information (Table)	9 Months Ended
	Jun. 30, 2018
Retirement Benefits, Description [Abstract]
Schedule of Net Benefit Costs	The components of our net periodic pension cost for our pension and other postretirement benefit plans for the three and nine months ended June 30, 2018 and 2017 are presented in the following tables. Most of these costs are recoverable through our tariff rates. A portion of these costs is capitalized into our rate base. The remaining costs are recorded as a component of operation and maintenance expense. In the second quarter of fiscal 2018, due to the retirement of certain executives, we recognized a settlement loss of $2.4 million associated with our Supplemental Executive Retirement Plan and revalued the net periodic pension cost for the remainder of fiscal 2018. The revaluation of the net periodic pension cost for our Supplemental Executive Retirement Plan resulted in an increase in the discount rate, effective March 1, 2018, to 4.12% from 3.89% , which will increase our net periodic pension cost by approximately $0.1 million for the remainder of the fiscal year. In the third quarter of fiscal 2018, due to the retirement of one of our executives, we recognized a settlement loss of $0.9 million associated with our Supplemental Executive Retirement Plan and revalued the net periodic pension cost for the remainder of fiscal 2018. The revaluation of the net periodic pension cost for our Supplemental Executive Retirement Plan resulted in an increase in the discount rate, effective June 5, 2018, to 4.29% from 4.12% , which will increase our net periodic pension cost by approximately $0.2 million for the remainder of the fiscal year. Three Months Ended June 30 Pension Benefits Other Benefits 2018 2017 2018 2017 (In thousands) Components of net periodic pension cost: Service cost $ 4,794 $ 5,216 $ 3,020 $ 3,109 Interest cost 6,448 6,296 2,726 2,669 Expected return on assets (6,917 ) (6,993 ) (2,002 ) (1,796 ) Amortization of prior service cost (credit) (57 ) (57 ) 2 (411 ) Amortization of actuarial (gain) loss 3,050 4,248 (1,618 ) (706 ) Settlements 888 — — — Net periodic pension cost $ 8,206 $ 8,710 $ 2,128 $ 2,865 Nine Months Ended June 30 Pension Benefits Other Benefits 2018 2017 2018 2017 (In thousands) Components of net periodic pension cost: Service cost $ 13,929 $ 15,649 $ 9,059 $ 9,327 Interest cost 19,311 18,890 8,180 8,009 Expected return on assets (20,750 ) (20,981 ) (6,005 ) (5,389 ) Amortization of prior service cost (credit) (173 ) (173 ) 8 (1,233 ) Amortization of actuarial (gain) loss 9,224 12,746 (4,855 ) (2,120 ) Settlements 3,303 — — — Net periodic pension cost $ 24,844 $ 26,131 $ 6,387 $ 8,594
Schedule of Assumptions Used	The assumptions used to develop our net periodic pension cost for the three and nine months ended June 30, 2018 and 2017 are as follows: Supplemental Executive Retirement Plan Pension Benefits Other Benefits 2018 2017 2018 2017 2018 2017 Discount rate 4.29% 3.73% 3.89% 3.73% 3.89% 3.73% Rate of compensation increase 3.50% 3.50% 3.50% 3.50% N/A N/A Expected return on plan assets N/A N/A 6.75% 7.00% 4.29% 4.45%

Financial Instruments (Table)

Financial Instruments (Table)	9 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following tables present the fair value and balance sheet classification of our financial instruments as of June 30, 2018 and September 30, 2017 . The gross amounts of recognized assets and liabilities are netted within our unaudited Condensed Consolidated Balance Sheets to the extent that we have netting arrangements with our counterparties. Balance Sheet Location Assets Liabilities (In thousands) June 30, 2018 Designated As Hedges: Interest rate contracts Other current assets / Other current liabilities $ — $ (75,763 ) Total — (75,763 ) Not Designated As Hedges: Commodity contracts Other current assets / Other current liabilities 869 (741 ) Commodity contracts Deferred charges and other assets / Deferred credits and other liabilities 108 — Total 977 (741 ) Gross Financial Instruments 977 (76,504 ) Gross Amounts Offset on Consolidated Balance Sheet: Contract netting — — Net Financial Instruments 977 (76,504 ) Cash collateral — — Net Assets/Liabilities from Risk Management Activities $ 977 $ (76,504 ) Balance Sheet Location Assets Liabilities (In thousands) September 30, 2017 Designated As Hedges: Interest rate contracts Deferred charges and other assets / Deferred credits and other liabilities $ — $ (112,076 ) Total — (112,076 ) Not Designated As Hedges: Commodity contracts Other current assets / Other current liabilities 2,436 (322 ) Commodity contracts Deferred charges and other assets / Deferred credits and other liabilities 803 — Total 3,239 (322 ) Gross Financial Instruments 3,239 (112,398 ) Gross Amounts Offset on Consolidated Balance Sheet: Contract netting — — Net Financial Instruments 3,239 (112,398 ) Cash collateral — — Net Assets/Liabilities from Risk Management Activities $ 3,239 $ (112,398 )
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss)	The following table summarizes the gains and losses arising from hedging transactions that were recognized as a component of other comprehensive income (loss), net of taxes, for the three and nine months ended June 30, 2018 and 2017 . The amounts included in the table below exclude gains and losses arising from ineffectiveness because those amounts are immediately recognized in the income statement as incurred. Three Months Ended Nine Months Ended 2018 2017 (1) 2018 2017 (1) (In thousands) Increase (decrease) in fair value: Interest rate agreements $ 7,861 $ (18,669 ) $ 28,315 $ 76,602 Forward commodity contracts (2) — — — 9,847 Recognition of (gains) losses in earnings due to settlements: Interest rate agreements 459 113 1,294 286 Forward commodity contracts (2) — — — (4,865 ) Total other comprehensive income (loss) from hedging, net of tax $ 8,320 $ (18,556 ) $ 29,609 $ 81,870 (1) Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction for the three and nine-month periods ended June 30, 2017. (2) Due to the sale of AEM, these amounts are included in income from discontinued operations.
Schedule Of Expected Deferred Gains (Losses) Recognition	The following amounts, net of deferred taxes, represent the expected recognition in earnings, as of June 30, 2018 , of the deferred losses recorded in AOCI associated with our financial instruments, based upon the fair values of these financial instruments at the date of settlement. However, the table below does not include the expected recognition in earnings of our outstanding interest rate agreements as those instruments have not yet settled. Interest Rate Agreements (In thousands) Next twelve months $ (1,848 ) Thereafter (46,808 ) Total $ (48,656 )

Fair Value Measurements (Table)

Fair Value Measurements (Table)	9 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables summarize, by level within the fair value hierarchy, our assets and liabilities that were accounted for at fair value on a recurring basis as of June 30, 2018 and September 30, 2017 . Assets and liabilities are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement. Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) (1) Significant Other Unobservable Inputs (Level 3) Netting and Cash Collateral June 30, 2018 (In thousands) Assets: Financial instruments $ — $ 977 $ — $ — $ 977 Available-for-sale securities Registered investment companies 43,548 — — — 43,548 Bond mutual funds 21,378 — — — 21,378 Bonds — 30,303 — — 30,303 Money market funds — 2,195 — — 2,195 Total available-for-sale securities 64,926 32,498 — — 97,424 Total assets $ 64,926 $ 33,475 $ — $ — $ 98,401 Liabilities: Financial instruments $ — $ 76,504 $ — $ — $ 76,504 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) (1) Significant Other Unobservable Inputs (Level 3) Netting and Cash Collateral September 30, 2017 (In thousands) Assets: Financial instruments $ — $ 3,239 $ — $ — $ 3,239 Available-for-sale securities Registered investment companies 41,097 — — — 41,097 Bond mutual funds 16,371 — — — 16,371 Bonds — 29,104 — — 29,104 Money market funds — 1,837 — — 1,837 Total available-for-sale securities 57,468 30,941 — — 88,409 Total assets $ 57,468 $ 34,180 $ — $ — $ 91,648 Liabilities: Financial instruments $ — $ 112,398 $ — $ — $ 112,398 (1) Our Level 2 measurements consist of over-the-counter options and swaps, which are valued using a market-based approach in which observable market prices are adjusted for criteria specific to each instrument, such as the strike price, notional amount or basis differences, municipal and corporate bonds, which are valued based on the most recent available quoted market prices and money market funds that are valued at cost.
Schedule of Available-for-sale Securities Reconciliation Table	Available-for-sale securities are comprised of the following: Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value (In thousands) As of June 30, 2018 Domestic equity mutual funds $ 28,283 $ 8,973 $ (293 ) $ 36,963 Foreign equity mutual funds 4,656 1,929 — 6,585 Bond mutual funds 21,673 — (295 ) 21,378 Bonds 30,434 8 (139 ) 30,303 Money market funds 2,195 — — 2,195 $ 87,241 $ 10,910 $ (727 ) $ 97,424 As of September 30, 2017 Domestic equity mutual funds $ 25,361 $ 8,920 $ — $ 34,281 Foreign equity mutual funds 4,581 2,235 — 6,816 Bond mutual funds 16,391 2 (22 ) 16,371 Bonds 29,074 46 (16 ) 29,104 Money market funds 1,837 — — 1,837 $ 77,244 $ 11,203 $ (38 ) $ 88,409
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments	The following table presents the carrying value and fair value of our debt as of June 30, 2018 and September 30, 2017 : June 30, 2018 September 30, 2017 (In thousands) Carrying Amount $ 3,085,000 $ 3,085,000 Fair Value $ 3,216,893 $ 3,382,272

Discontinued Operations (Table)

Discontinued Operations (Table)	9 Months Ended
	Jun. 30, 2018
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations	The following table presents statement of income data related to discontinued operations: Nine Months Ended (In thousands) Operating revenues $ 303,474 Purchased gas cost 277,554 Operating expenses 7,874 Operating income 18,046 Other nonoperating expense (211 ) Income from discontinued operations before income taxes 17,835 Income tax expense 6,841 Income from discontinued operations 10,994 Gain on sale from discontinued operations, net of tax ($10,215) 2,716 Net income from discontinued operations $ 13,710 The following table presents statement of cash flow data related to discontinued operations: Nine Months Ended (In thousands) Depreciation and amortization expense $ 185 Capital expenditures $ — Non-cash loss in commodity contract cash flow hedges $ (8,165 )
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location	The impact of our natural gas marketing segment commodity contracts designated as fair value hedges and the related hedged item on the results of discontinued operations on our condensed consolidated income statement for the nine months ended June 30, 2017 is presented below. Nine Months Ended (In thousands) Commodity contracts $ (9,567 ) Fair value adjustment for natural gas inventory designated as the hedged item 12,858 Total decrease in purchased gas cost reflected in income from discontinued operations $ 3,291 The decrease in purchased gas cost reflected in income from discontinued operations is comprised of the following: Basis ineffectiveness $ (597 ) Timing ineffectiveness 3,888 $ 3,291
Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location	The impact of our natural gas marketing segment cash flow hedges on our condensed consolidated income statements for the nine months ended June 30, 2017 is presented below: Nine Months Ended (In thousands) Loss reclassified from AOCI for effective portion of natural gas marketing commodity contracts $ (2,612 ) Gain arising from ineffective portion of natural gas marketing commodity contracts 111 Gain on discontinuance of cash flow hedging of natural gas marketing commodity contracts reclassified from AOCI 10,579 Total impact on purchased gas cost reflected in income from discontinued operations $ 8,078

Nature of Business (Details)

Nature of Business (Details)	Jun. 30, 2018customerstateregulated_distribution_division
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of customers serviced | customer	3,000,000
Number of regulated distribution divisions | regulated_distribution_division	6
Number of states with service areas | state	8

Unaudited Financial Informati33

Unaudited Financial Information (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Regulatory Asset [Line Items]
Regulatory assets	$ 129,743	$ 176,798
Regulatory asset - future recoverable pension costs	7,100	9,400
Regulatory Liabilities [Line Items]
Regulatory liabilities	1,499,747	555,657
Regulatory excess deferred taxes
Regulatory Liabilities [Line Items]
Regulatory liabilities	737,746	0
Regulatory cost of service reserve
Regulatory Liabilities [Line Items]
Regulatory liabilities	30,930	0
Regulatory cost of removal obligation
Regulatory Liabilities [Line Items]
Regulatory liabilities	528,709	521,330
Deferred gas costs
Regulatory Liabilities [Line Items]
Regulatory liabilities	159,201	15,559
Asset retirement obligation
Regulatory Liabilities [Line Items]
Regulatory liabilities	12,827	12,827
APT annual adjustment mechanism
Regulatory Liabilities [Line Items]
Regulatory liabilities	20,551	0
Other
Regulatory Liabilities [Line Items]
Regulatory liabilities	9,783	5,941
Pension and postretirement benefit costs
Regulatory Asset [Line Items]
Regulatory assets	17,546	26,826
Infrastructure mechanisms
Regulatory Asset [Line Items]
Regulatory assets	77,387	46,437
Deferred gas costs
Regulatory Asset [Line Items]
Regulatory assets	347	65,714
Recoverable loss on reacquired debt
Regulatory Asset [Line Items]
Regulatory assets	9,328	11,208
Deferred pipeline record collection costs
Regulatory Asset [Line Items]
Regulatory assets	16,963	11,692
APT annual adjustment mechanism
Regulatory Asset [Line Items]
Regulatory assets	0	2,160
Rate case costs
Regulatory Asset [Line Items]
Regulatory assets	3,041	2,629
Other
Regulatory Asset [Line Items]
Regulatory assets	5,131	$ 10,132
Other Current Liabilities | Regulatory excess deferred taxes
Regulatory Liabilities [Line Items]
Regulatory liabilities	$ 4,200

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	$ 562,245	$ 526,501	$ 2,670,846	$ 2,294,855
Purchased gas cost	130,886	114,176	1,124,763	852,975
Operation and maintenance expense	145,075	128,690	435,715	385,867
Depreciation and amortization expense	90,671	80,023	268,426	234,648
Taxes, other than income	72,620	62,948	208,400	185,611
Operating income	122,993	140,664	633,542	635,754
Miscellaneous expense	(2,003)	(289)	(4,291)	(450)
Interest charges	23,349	28,498	82,162	86,472
Income before income taxes	97,641	111,877	547,089	548,832
Income tax (benefit) expense	26,448	41,069	(17,228)	201,974
Income from continuing operations	71,193	70,808	564,317	346,858
Income from discontinued operations, net of tax			0	10,994
Gain on sale of discontinued operations, net of tax			0	2,716
Net income	71,193	70,808	564,317	360,568
Capital expenditures	394,494	252,763	1,088,472	812,148
Segment Reporting Information, Balance Sheet [Abstract]
Property, plant and equipment, net	10,071,860		10,071,860		$ 9,259,182
Total assets	11,507,624		11,507,624		10,749,596
Operating Segments | Distribution
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	535,488	494,060	2,595,571	2,211,257
Purchased gas cost	230,887	197,767	1,421,698	1,106,209
Operation and maintenance expense	111,895	99,631	347,623	296,048
Depreciation and amortization expense	66,504	62,760	197,587	185,219
Taxes, other than income	64,420	56,850	184,219	165,032
Operating income	61,782	77,052	444,444	458,749
Miscellaneous expense	(1,191)	(62)	(2,198)	334
Interest charges	13,315	18,394	51,581	56,437
Income before income taxes	47,276	58,596	390,665	402,646
Income tax (benefit) expense	11,932	22,082	(39,021)	149,623
Income from continuing operations				253,023
Income from discontinued operations, net of tax				0
Gain on sale of discontinued operations, net of tax				0
Net income	35,344	36,514	429,686	253,023
Capital expenditures	284,209	205,780	749,693	636,449
Segment Reporting Information, Balance Sheet [Abstract]
Property, plant and equipment, net	7,427,486		7,427,486		6,849,517
Total assets	10,840,846		10,840,846		10,050,164
Operating Segments | Pipeline and Storage
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	127,633	117,283	375,051	339,207
Purchased gas cost	561	1,251	1,906	2,331
Operation and maintenance expense	33,494	29,059	89,027	89,863
Depreciation and amortization expense	24,167	17,263	70,839	49,429
Taxes, other than income	8,200	6,098	24,181	20,579
Operating income	61,211	63,612	189,098	177,005
Miscellaneous expense	(812)	(227)	(2,093)	(784)
Interest charges	10,034	10,104	30,581	30,035
Income before income taxes	50,365	53,281	156,424	146,186
Income tax (benefit) expense	14,516	18,987	21,793	52,351
Income from continuing operations				93,835
Income from discontinued operations, net of tax				0
Gain on sale of discontinued operations, net of tax				0
Net income	35,849	34,294	134,631	93,835
Capital expenditures	110,285	46,983	338,779	175,699
Segment Reporting Information, Balance Sheet [Abstract]
Property, plant and equipment, net	2,644,374		2,644,374		2,409,665
Total assets	2,866,266		2,866,266		2,621,601
Operating Segments | Natural Gas Marketing
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues		0		0
Purchased gas cost		0		0
Operation and maintenance expense		0		0
Depreciation and amortization expense		0		0
Taxes, other than income		0		0
Operating income		0		0
Miscellaneous expense		0		0
Interest charges		0		0
Income before income taxes		0		0
Income tax (benefit) expense		0		0
Income from continuing operations				0
Income from discontinued operations, net of tax				10,994
Gain on sale of discontinued operations, net of tax				2,716
Net income		0		13,710
Capital expenditures		0		0
Eliminations
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	(100,876)	(84,842)	(299,776)	(255,609)
Purchased gas cost	(100,562)	(84,842)	(298,841)	(255,565)
Operation and maintenance expense	(314)	0	(935)	(44)
Depreciation and amortization expense	0	0	0	0
Taxes, other than income	0	0	0	0
Operating income	0	0	0	0
Miscellaneous expense	0	0	0	0
Interest charges	0	0	0	0
Income before income taxes	0	0	0	0
Income tax (benefit) expense	0	0	0	0
Income from continuing operations				0
Income from discontinued operations, net of tax				0
Gain on sale of discontinued operations, net of tax				0
Net income	0	0	0	0
Capital expenditures	0	0	0	0
Segment Reporting Information, Balance Sheet [Abstract]
Property, plant and equipment, net	0		0		0
Total assets	(2,199,488)		(2,199,488)		$ (1,922,169)
Reportable Subsegments
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	562,245	526,501	2,670,846	2,294,855
Reportable Subsegments | Distribution
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	534,816	493,738	2,593,578	2,210,221
Reportable Subsegments | Pipeline and Storage
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	27,429	32,763	77,268	84,634
Reportable Subsegments | Natural Gas Marketing
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues		0		0
Reportable Subsegments | Eliminations
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	0	0	0	0
Intersubsegment Eliminations
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	0	0	0	0
Intersubsegment Eliminations | Distribution
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	672	322	1,993	1,036
Intersubsegment Eliminations | Pipeline and Storage
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	100,204	84,520	297,783	254,573
Intersubsegment Eliminations | Natural Gas Marketing
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues		0		0
Intersubsegment Eliminations | Eliminations
Segment Reporting Information Profit Loss [Abstract]
Total operating revenues	$ (100,876)	$ (84,842)	$ (299,776)	$ (255,609)

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Basic and Diluted Earnings Per Share from continuing operations
Income from continuing operations	$ 71,193	$ 70,808	$ 564,317	$ 346,858
Less: Income from continuing operations allocated to participating securities	59	75	545	424
Income from continuing operations available to common shareholders	$ 71,134	$ 70,733	$ 563,772	$ 346,434
Basic and diluted weighted average shares outstanding (in shares)	111,851	106,364	110,707	105,862
Income from continuing operations per share — Basic and Diluted (USD per share)	$ 0.64	$ 0.67	$ 5.09	$ 3.27
Basic and Diluted Earnings Per Share from discontinued operations
Income from discontinued operations	$ 0	$ 0	$ 0	$ 13,710
Less: Income from discontinued operations allocated to participating securities	0	0	0	15
Income from discontinued operations available to common shareholders	$ 0	$ 0	$ 0	$ 13,695
Basic and diluted weighted average shares outstanding (in shares)	111,851	106,364	110,707	105,862
Income from discontinued operations per share — Basic and Diluted (USD per share)	$ 0	$ 0	$ 0	$ 0.13
Net income per share — Basic and Diluted (USD per share)	$ 0.64	$ 0.67	$ 5.09	$ 3.40

Debt - Schedule of Long-term De

Debt - Schedule of Long-term Debt Instruments (Details) - USD ($)	Jun. 30, 2018	Sep. 30, 2017
Debt Instrument [Line Items]
Total long-term debt	$ 3,085,000,000	$ 3,085,000,000
Original issue (premium) / discount on unsecured senior notes and debentures	(4,425,000)	(4,384,000)
Debt issuance cost	21,110,000	22,339,000
Current maturities	450,000,000	0
Long-term debt	2,618,315,000	3,067,045,000
Unsecured 8.50% Senior Notes, due March 2019
Debt Instrument [Line Items]
Total long-term debt	$ 450,000,000	$ 450,000,000
Interest rate	8.50%	8.50%
Unsecured 3.00% Senior Notes, due 2027
Debt Instrument [Line Items]
Total long-term debt	$ 500,000,000	$ 500,000,000
Interest rate	3.00%	3.00%
Unsecured 5.95% Senior Notes, due 2034
Debt Instrument [Line Items]
Total long-term debt	$ 200,000,000	$ 200,000,000
Interest rate	5.95%	5.95%
Unsecured 5.50% Senior Notes, due 2041
Debt Instrument [Line Items]
Total long-term debt	$ 400,000,000	$ 400,000,000
Interest rate	5.50%	5.50%
Unsecured 4.15% Senior Notes, due 2043
Debt Instrument [Line Items]
Total long-term debt	$ 500,000,000	$ 500,000,000
Interest rate	4.15%	4.15%
Unsecured 4.125% Senior Notes, due 2044
Debt Instrument [Line Items]
Total long-term debt	$ 750,000,000	$ 750,000,000
Interest rate	4.125%	4.125%
Medium-term note Series A, 1995-1, 6.67%, due 2025
Debt Instrument [Line Items]
Total long-term debt	$ 10,000,000	$ 10,000,000
Interest rate	6.67%	6.67%
Unsecured 6.75% Debentures, due 2028
Debt Instrument [Line Items]
Total long-term debt	$ 150,000,000	$ 150,000,000
Interest rate	6.75%	6.75%
Floating-rate term loan, due September 2019
Debt Instrument [Line Items]
Total long-term debt	$ 125,000,000	$ 125,000,000
Maximum borrowing capacity	$ 200,000,000	$ 200,000,000

Debt - Narrative (Details)

Debt - Narrative (Details) - USD ($)	Mar. 26, 2018	Jun. 30, 2018	Sep. 30, 2017
Line Of Credit Facility [Line Items]
Maximum borrowing capacity		$ 1,500,000,000
Maximum debt-to-total-capitalization ratio		70.00%
Debt-to-total-capitalization ratio		42.00%
Minimum
Line Of Credit Facility [Line Items]
Equity-to-total-capitalization ratio		50.00%
Outstanding indebtedness		$ 15,000,000
Maximum
Line Of Credit Facility [Line Items]
Equity-to-total-capitalization ratio		60.00%
Outstanding indebtedness		$ 100,000,000
Five Year Unsecured Revolving Credit Agreement
Line Of Credit Facility [Line Items]
Outstanding commercial paper		244,800,000	$ 447,700,000
Five Year Unsecured Revolving Credit Agreement | Commercial Paper
Line Of Credit Facility [Line Items]
Maximum borrowing capacity		$ 1,500,000,000
Loan term		5 years
Loan extension term	1 year
Accordion feature		$ 250,000,000
Maximum borrowing capacity post accordion feature		1,750,000,000
$25 Million Bank Loan Agreement | Line of Credit
Line Of Credit Facility [Line Items]
Maximum borrowing capacity		25,000,000
Outstanding borrowings		0
$10 Million Revolving Credit Note | Revolving Credit Facility
Line Of Credit Facility [Line Items]
Maximum borrowing capacity		10,000,000
Outstanding borrowings		0
Remaining borrowing capacity		$ 4,400,000
LIBOR | Five Year Unsecured Revolving Credit Agreement | Commercial Paper | Minimum
Line Of Credit Facility [Line Items]
Interest rate spread		0.00%
LIBOR | Five Year Unsecured Revolving Credit Agreement | Commercial Paper | Maximum
Line Of Credit Facility [Line Items]
Interest rate spread		1.25%

Impact of the Tax Cuts and Jo38

Impact of the Tax Cuts and Jobs Act of 2017 (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2018	Sep. 30, 2017
Income Tax Examination [Line Items]
Effective federal tax rate			24.50%
Reduction in deferred tax liability			$ 903,700
Regulated operations recorded as a regulatory liability	$ 738,200		738,200
Regulatory liability amortized	500
One-time tax benefit			165,500
Remeasured federal net operating loss carryforwards	270,700		270,700
Federal alternative minimum tax credit carryforwards	10,100		10,100
Remeasured charitable contribution carryforwards	5,300		5,300
State net operating loss carryforwards	21,200		21,200
State tax credit carryforwards	1,500		1,500
State net operating loss carryforwards, federal effects	5,600		5,600
State tax credit carryforwards, federal effects	400		400
Valuation allowance reduction		$ 4,200
Regulatory liability	1,499,747		$ 1,499,747	$ 555,657
Minimum
Income Tax Examination [Line Items]
Return issuance period			18 years
Maximum
Income Tax Examination [Line Items]
Return issuance period			40 years
Regulatory cost of service reserve
Income Tax Examination [Line Items]
Regulatory liability	$ 30,930		$ 30,930	$ 0

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - USD ($)	Nov. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Nov. 14, 2017	Sep. 30, 2017	Mar. 28, 2016
Class of Stock [Line Items]
Common stock authorized (in shares)		200,000,000			200,000,000
Net proceeds from equity offering		$ 395,092,000	$ 98,755,000
Shelf Registration Statement
Class of Stock [Line Items]
Debt and equity securities authorized for issuance						$ 2,500,000,000
Debt and equity securities authorized for issuance value remaining		$ 650,000,000
At-The-Market
Class of Stock [Line Items]
Value of shares authorized for issuance				$ 500,000,000
Common stock sold (in shares)		0
Underwriting Agreement
Class of Stock [Line Items]
Common stock authorized (in shares)	4,558,404
Gross proceeds from equity offering	$ 400,000,000
Net proceeds from equity offering	$ 395,100,000

Shareholders' Equity - Schedule

Shareholders' Equity - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	$ 3,898,666
Shareholders' equity, ending balance	4,759,552
Available- for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	7,048	$ 4,484
Other comprehensive income before reclassifications	148	1,485
Amounts reclassified from accumulated other comprehensive income	(884)	68
Net current-period other comprehensive income (loss)	(736)	1,553
Shareholders' equity, ending balance	6,312	6,037
Cash Flow Hedges | Interest rate agreements
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	(112,302)	(187,524)
Other comprehensive income before reclassifications	28,315	76,602
Amounts reclassified from accumulated other comprehensive income	1,294	286
Net current-period other comprehensive income (loss)	29,609	76,888
Shareholders' equity, ending balance	(82,693)	(110,636)
Cash Flow Hedges | Commodity contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance		(4,982)
Other comprehensive income before reclassifications		9,847
Amounts reclassified from accumulated other comprehensive income		(4,865)
Net current-period other comprehensive income (loss)		4,982
Shareholders' equity, ending balance		0
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	(105,254)	(188,022)
Other comprehensive income before reclassifications	28,463	87,934
Amounts reclassified from accumulated other comprehensive income	410	(4,511)
Net current-period other comprehensive income (loss)	28,873	83,423
Shareholders' equity, ending balance	$ (76,381)	$ (104,599)

Shareholders' Equity - Reclassi

Shareholders' Equity - Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Operation and maintenance expense	$ 145,075	$ 128,690	$ 435,715	$ 385,867
Total before tax	97,641	111,877	547,089	548,832
Income tax (benefit) expense	(26,448)	(41,069)	17,228	(201,974)
Interest charges	(23,349)	(28,498)	(82,162)	(86,472)
Purchased gas cost	130,886	114,176	1,124,763	852,975
Amount Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	(454)	(113)	(410)	4,511
Amount Reclassified from Accumulated Other Comprehensive Income | Available- for-Sale Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Operation and maintenance expense	7		1,146	(107)
Total before tax	7		1,146	(107)
Income tax (benefit) expense	(2)		(262)	39
Net of tax	5		884	(68)
Amount Reclassified from Accumulated Other Comprehensive Income | Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(594)	(177)	(1,781)	7,517
Income tax (benefit) expense	135	64	487	(2,938)
Net of tax	(459)		(1,294)	4,579
Amount Reclassified from Accumulated Other Comprehensive Income | Cash Flow Hedges | Interest rate agreements
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest charges	$ (594)	$ (177)	$ (1,781)	(450)
Amount Reclassified from Accumulated Other Comprehensive Income | Cash Flow Hedges | Commodity contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Purchased gas cost				$ 7,967

Interim Pension and Other Pos42

Interim Pension and Other Postretirement Benefit Plan Information - Narrative (Details) - USD ($) $ in Thousands	Jun. 05, 2018	Mar. 01, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Supplemental Executive Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Settlements loss			$ 900	$ 2,400
Discount rate	4.29%	4.12%	4.29%		3.89%	3.73%	4.29%	3.73%
Increase our net periodic pension cost	$ 200	$ 100
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlements loss			$ 0			$ 0	$ 0	$ 0
Discount rate			3.89%			3.73%	3.89%	3.73%
Benefit plan contribution amount							$ 11,400
Other Benefits | Minimum
Defined Benefit Plan Disclosure [Line Items]
Benefit plan expected contribution amount			$ 10,000				10,000
Other Benefits | Maximum
Defined Benefit Plan Disclosure [Line Items]
Benefit plan expected contribution amount			$ 20,000				$ 20,000

Interim Pension and Other Pos43

Interim Pension and Other Postretirement Benefit Plan Information - Schedule of Net Benefit Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4,794	$ 5,216	$ 13,929	$ 15,649
Interest cost	6,448	6,296	19,311	18,890
Expected return on assets	(6,917)	(6,993)	(20,750)	(20,981)
Amortization of prior service cost (credit)	(57)	(57)	(173)	(173)
Amortization of actuarial (gain) loss	3,050	4,248	9,224	12,746
Settlements loss	888	0	3,303	0
Net periodic pension cost	8,206	8,710	24,844	26,131
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	3,020	3,109	9,059	9,327
Interest cost	2,726	2,669	8,180	8,009
Expected return on assets	(2,002)	(1,796)	(6,005)	(5,389)
Amortization of prior service cost (credit)	2	(411)	8	(1,233)
Amortization of actuarial (gain) loss	(1,618)	(706)	(4,855)	(2,120)
Settlements loss	0	0	0	0
Net periodic pension cost	$ 2,128	$ 2,865	$ 6,387	$ 8,594

Interim Pension and Other Pos44

Interim Pension and Other Postretirement Benefit Plan Information - Schedule of Assumptions Used (Details)	Jun. 05, 2018	Mar. 01, 2018	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Supplemental Executive Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.29%	4.12%	4.29%	3.89%	3.73%	4.29%	3.73%
Rate of compensation increase			3.50%		3.50%	3.50%	3.50%
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate			3.89%		3.73%	3.89%	3.73%
Rate of compensation increase			3.50%		3.50%	3.50%	3.50%
Expected return on plan assets			6.75%		7.00%	6.75%	7.00%
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate			3.89%		3.73%	3.89%	3.73%
Expected return on plan assets			4.29%		4.45%	4.29%	4.45%

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Mar. 29, 2018USD ($)	Jun. 30, 2018USD ($)Bcf
Loss Contingencies [Line Items]
Self-insurance retention expense | $		$ 1
Civil Action, Dallas, Texas
Loss Contingencies [Line Items]
Damages sought | $	$ 1
Supply Commitment
Loss Contingencies [Line Items]
Purchase commitment contract term		1 year
Within one year | Supply Commitment
Loss Contingencies [Line Items]
Purchase commitment contract term		1 year
Purchase commitment amount within one year | Bcf		53,600
Within two to three years | Supply Commitment
Loss Contingencies [Line Items]
Purchase commitment amount within one year | Bcf		51,200
Minimum | Within two to three years | Supply Commitment
Loss Contingencies [Line Items]
Purchase commitment contract term		2 years
Maximum | Within two to three years | Supply Commitment
Loss Contingencies [Line Items]
Purchase commitment contract term		3 years

Financial Instruments - Narrati

Financial Instruments - Narrative (Details)	3 Months Ended		9 Months Ended
	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)BcfMMcf	Jun. 30, 2017USD ($)
Derivative [Line Items]
Net realized gain (loss)	$ (48,700,000)		$ (48,700,000)
Net gain (loss) on settled interest rate agreements	$ (600,000)	$ (200,000)	$ (1,800,000)	$ (500,000)
Gas Purchases | Not Designated as Hedging Instrument | Commodity contracts
Derivative [Line Items]
Hedging percent	26.00%		26.00%
Energy measure | Bcf			15,000
Minimum | Gas Purchases | Not Designated as Hedging Instrument | Commodity contracts
Derivative [Line Items]
Hedging percent	25.00%		25.00%
Maximum | Gas Purchases | Not Designated as Hedging Instrument | Commodity contracts
Derivative [Line Items]
Hedging percent	50.00%		50.00%
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Swap
Derivative [Line Items]
Notional amount	$ 450,000,000		$ 450,000,000
Interest rate hedged	3.78%		3.78%
Long | Gas Purchases | Not Designated as Hedging Instrument | Commodity contracts
Derivative [Line Items]
Energy measure | MMcf			11,446

Financial Instruments - Schedul

Financial Instruments - Schedule of Derivative Instruments in Statement of Financial Position, Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets	$ 977	$ 3,239
Contract netting, Assets	0	0
Net Financial Instruments, Assets	977	3,239
Cash collateral, Assets	0	0
Net Assets/Liabilities from Risk Management Activities, Assets	977	3,239
Gross Financial Instruments, Liabilities	(76,504)	(112,398)
Contract netting, Liabilities	0	0
Net Financial Instruments, Liabilities	(76,504)	(112,398)
Cash collateral, Liabilities	0	0
Net Assets/Liabilities from Risk Management Activities, Liabilities	(76,504)	(112,398)
Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets	0	0
Gross Financial Instruments, Liabilities	(75,763)	(112,076)
Designated as Hedging Instrument | Other Current Assets | Interest rate agreements
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets	0
Designated as Hedging Instrument | Other Current Liabilities | Interest rate agreements
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Liabilities	(75,763)
Designated as Hedging Instrument | Deferred Charges and Other Assets | Interest rate agreements
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets		0
Designated as Hedging Instrument | Deferred Credits and Other Liabilities | Interest rate agreements
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Liabilities		(112,076)
Not Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets	977	3,239
Gross Financial Instruments, Liabilities	(741)	(322)
Not Designated as Hedging Instrument | Other Current Assets | Commodity contracts
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets	869	2,436
Not Designated as Hedging Instrument | Other Current Liabilities | Commodity contracts
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Liabilities	(741)	(322)
Not Designated as Hedging Instrument | Deferred Charges and Other Assets | Commodity contracts
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Assets	108	803
Not Designated as Hedging Instrument | Deferred Credits and Other Liabilities | Commodity contracts
Derivatives Fair Value [Line Items]
Gross Financial Instruments, Liabilities	$ 0	$ 0

Financial Instruments - Sched48

Financial Instruments - Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Increase (decrease) in fair value:
Interest rate agreements	$ 7,861	$ (18,669)	$ 28,315	$ 76,602
Forward commodity contracts	0	0	0	9,847
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Interest rate agreements	459	113	1,294	286
Forward commodity contracts	0	0	0	(4,865)
Total other comprehensive income (loss) from hedging, net of tax	$ 8,320	$ (18,556)	$ 29,609	$ 81,870
Minimum
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Effective income tax rate				37.00%
Maximum
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Effective income tax rate				39.00%

Financial Instruments - Sched49

Financial Instruments - Schedule Of Expected Deferred Gains (Losses) Recognition (Details) $ in Thousands	Jun. 30, 2018USD ($)
Derivative [Line Items]
Interest Rate Agreements	$ (48,656)
Next twelve months
Derivative [Line Items]
Interest Rate Agreements	(1,848)
Thereafter
Derivative [Line Items]
Interest Rate Agreements	$ (46,808)

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Netting and Cash Collateral	$ 0	$ 0
Financial instruments net assets	977	3,239
Total available-for-sale securities	97,424	88,409
Total assets	98,401	91,648
Netting and Cash Collateral	0	0
Financial instruments net liability	76,504	112,398
Registered investment companies
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	43,548	41,097
Bond mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	21,378	16,371
Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	30,303	29,104
Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	2,195	1,837
Fair Value Inputs Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial instruments gross assets	0	0
Total available-for-sale securities	64,926	57,468
Total assets	64,926	57,468
Financial instruments gross liability	0	0
Fair Value Inputs Level 1 | Registered investment companies
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	43,548	41,097
Fair Value Inputs Level 1 | Bond mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	21,378	16,371
Fair Value Inputs Level 1 | Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 1 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial instruments gross assets	977	3,239
Total available-for-sale securities	32,498	30,941
Total assets	33,475	34,180
Financial instruments gross liability	76,504	112,398
Fair Value Inputs Level 2 | Registered investment companies
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 2 | Bond mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 2 | Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	30,303	29,104
Fair Value Inputs Level 2 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	2,195	1,837
Fair Value Inputs Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial instruments gross assets	0	0
Total available-for-sale securities	0	0
Total assets	0	0
Financial instruments gross liability	0	0
Fair Value Inputs Level 3 | Registered investment companies
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 3 | Bond mutual funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 3 | Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	0	0
Fair Value Inputs Level 3 | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total available-for-sale securities	$ 0	$ 0

Fair Value Measurements - Sch51

Fair Value Measurements - Schedule of Available-for-sale Securities Reconciliation Table (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 87,241	$ 77,244
Gross Unrealized Gain	10,910	11,203
Gross Unrealized Loss	(727)	(38)
Fair Value	97,424	88,409
Domestic equity mutual funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	28,283	25,361
Gross Unrealized Gain	8,973	8,920
Gross Unrealized Loss	(293)	0
Fair Value	36,963	34,281
Foreign equity mutual funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4,656	4,581
Gross Unrealized Gain	1,929	2,235
Gross Unrealized Loss	0	0
Fair Value	6,585	6,816
Bond mutual funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	21,673	16,391
Gross Unrealized Gain	0	2
Gross Unrealized Loss	(295)	(22)
Fair Value	21,378	16,371
Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	30,434	29,074
Gross Unrealized Gain	8	46
Gross Unrealized Loss	(139)	(16)
Fair Value	30,303	29,104
Money market funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	2,195	1,837
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	0
Fair Value	$ 2,195	$ 1,837

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Assets held in separate rabbi trusts	$ 45.7	$ 42.9

Fair Value Measurements - Sch53

Fair Value Measurements - Schedule of Carrying Values and Estimated Fair Values of Debt Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Total long-term debt	$ 3,085,000	$ 3,085,000
Fair Value	$ 3,216,893	$ 3,382,272

Discontinued Operations - Narra

Discontinued Operations - Narrative (Details) - Natural Gas Marketing - Discontinued Operations, Disposed of by Sale - USD ($) $ / shares in Units, $ in Millions	Jan. 01, 2017	Jan. 31, 2018	Mar. 31, 2017	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash purchase price	$ 38.3
Working capital	109
Total consideration	147.3
Escrow deposit	$ 7
Escrow released		$ 3
Net gain per diluted share (USD per share)			$ 0.03
Pretax gain recognized				$ 10.6
Cash flow hedge ineffectiveness				3.4
Decrease in purchased gas cost				$ 6.8

Discontinued Operations - Dispo

Discontinued Operations - Disposal Groups, Including Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense			$ 0	$ 6,841
Income from discontinued operations			0	10,994
Gain on sale from discontinued operations, net of tax ($10,215)			0	2,716
Net income from discontinued operations	$ 0	$ 0	0	13,710
Gain on sale of discontinued operations, tax			$ 0	10,215
Natural Gas Marketing | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating revenues				303,474
Purchased gas cost				277,554
Operating expenses				7,874
Operating income				18,046
Other nonoperating expense				(211)
Income from discontinued operations before income taxes				17,835
Income tax expense				6,841
Income from discontinued operations				10,994
Gain on sale from discontinued operations, net of tax ($10,215)				2,716
Net income from discontinued operations				13,710
Depreciation and amortization expense				185
Capital expenditures				0
Non-cash loss in commodity contract cash flow hedges				$ (8,165)

Discontinued Operations - Sched

Discontinued Operations - Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - Natural Gas Marketing - Discontinued Operations, Disposed of by Sale $ in Thousands	9 Months Ended
	Jun. 30, 2017USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Commodity contracts	$ (9,567)
Fair value adjustment for natural gas inventory designated as the hedged item	12,858
Total decrease in purchased gas cost reflected in income from discontinued operations	3,291
The decrease in purchased gas cost reflected in income from discontinued operations is comprised of the following:
Basis ineffectiveness	(597)
Timing ineffectiveness	3,888
Total decrease in purchased gas cost reflected in income from discontinued operations	$ 3,291

Discontinued Operations - Sch57

Discontinued Operations - Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on discontinuance of cash flow hedging of natural gas marketing commodity contracts reclassified from AOCI	$ 0	$ 10,579
Natural Gas Marketing | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss reclassified from AOCI for effective portion of natural gas marketing commodity contracts		(2,612)
Gain arising from ineffective portion of natural gas marketing commodity contracts		111
Gain on discontinuance of cash flow hedging of natural gas marketing commodity contracts reclassified from AOCI		10,579
Total impact on purchased gas cost reflected in income from discontinued operations		$ 8,078