Atmos Energy (ATO) 10-Q 6 Aug 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Jun. 30, 2014	Aug. 01, 2014
Document And Entity Information [Abstract]	'	'
Entity Registrant Name	'Atmos Energy Corporation	'
Entity Central Index Key	'0000731802	'
Current Fiscal Year End Date	'--09-30	'
Entity Filer Category	'Large Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	100,351,676
Entity Well-known Seasoned Issuer	'Yes	'
Entity Voluntary Filers	'No	'
Entity Current Reporting Status	'Yes	'

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
ASSETS	'	'
Property, plant and equipment	$8,217,954	$7,722,019
Less accumulated depreciation and amortization	1,756,504	1,691,364
Net property, plant and equipment	6,461,450	6,030,655
Current assets	'	'
Cash and cash equivalents	51,421	66,199
Accounts receivable, net	388,874	301,992
Gas stored underground	207,458	244,741
Other current assets	126,890	64,201
Total current assets	774,643	677,133
Goodwill	741,363	741,363
Deferred charges and other assets	379,733	485,117
Total assets	8,357,189	7,934,268
Shareholders' equity	'	'
Common stock, no par value (stated at $.005 per share)	502	453
Additional paid-in capital	2,172,307	1,765,811
Retained earnings	932,576	775,267
Accumulated other comprehensive income (loss)	11,300	38,878
Shareholders' equity	3,116,685	2,580,409
Long-term debt	1,955,907	2,455,671
Total capitalization	5,072,592	5,036,080
Current liabilities	'	'
Accounts payable and accrued liabilities	312,671	241,611
Other current liabilities	343,026	368,891
Short-term debt	0	367,984
Current maturities of long-term debt	500,000	0
Total current liabilities	1,155,697	978,486
Deferred income taxes	1,341,294	1,164,053
Regulatory cost of removal obligation	391,785	359,299
Pension and postretirement liabilities	347,344	358,787
Deferred credits and other liabilities	48,477	37,563
Total shareholders' equity and liabilities	$8,357,189	$7,934,268

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (PARENTHETICALS) (USD $)	Jun. 30, 2014	Sep. 30, 2013
Statement of Financial Position [Abstract]	'	'
Common Stock, Par Value Per Share	$0	$0
Common Stock, Stated Value Per Share	$0.01	$0.01
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares, Issued	100,346,468	90,640,211
Common Stock, Shares, Outstanding	100,346,468	90,640,211

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Operating revenues	'	'	'	'
Operating revenues	$942,718	$857,935	$4,162,188	$3,201,086
Purchased gas cost	'	'	'	'
Purchased gas cost	583,185	541,438	2,917,421	2,089,476
Gross profit	359,533	316,497	1,244,767	1,111,610
Operating expenses	'	'	'	'
Operation and maintenance	125,559	121,258	365,991	338,871
Depreciation and amortization	63,955	58,129	185,731	174,888
Taxes, other than income	63,414	50,714	165,640	146,355
Total operating expenses	252,928	230,101	717,362	660,114
Operating income	106,605	86,396	527,405	451,496
Miscellaneous income (expense)	-374	-467	-4,022	1,943
Interest charges	31,840	32,741	95,556	96,594
Income (loss) before income taxes	74,391	53,188	427,827	356,845
Income tax expense (benefit)	28,670	19,714	161,723	133,683
Income (loss) from continuing operations	45,721	33,474	266,104	223,162
Income from discontinued operations, net of tax	0	0	0	7,202
Gain on sale of discontinued operations, net of tax	0	5,294	0	5,294
Net income (loss)	45,721	38,768	266,104	235,658
Income (Loss) From Continuing Operations Per Basic Share	$0.45	$0.37	$2.78	$2.46
Income (Loss) From Discontinued Operations Net Of Tax Per Basic Share	$0	$0.06	$0	$0.14
Basic net income (loss) per share	$0.45	$0.43	$2.78	$2.60
Income (Loss) From Continuing Operations Per Diluted Share	$0.45	$0.36	$2.76	$2.43
Income (Loss) From Discontinued Operations Net Of Tax Per Diluted Share	$0	$0.06	$0	$0.14
Diluted net income (loss) per share	$0.45	$0.42	$2.76	$2.57
Cash dividends per share	$0.37	$0.35	$1.11	$1.05
Weighted average shares outstanding:	'	'	'	'
Basic weighted average shares outstanding	100,267	90,603	95,455	90,497
Diluted weighted average shares outstanding	101,150	91,550	96,339	91,445
Natural Gas Distribution Segment [Member]	'	'	'	'
Operating revenues	'	'	'	'
Operating revenues	517,707	467,144	2,652,532	2,039,107
Purchased gas cost	'	'	'	'
Purchased gas cost	260,042	227,649	1,710,508	1,172,975
Gross profit	257,665	239,495	942,024	866,132
Operating expenses	'	'	'	'
Operation and maintenance	92,994	93,490	289,433	266,570
Depreciation and amortization	52,542	48,368	152,113	146,059
Taxes, other than income	57,596	45,686	155,286	132,029
Total operating expenses	203,132	187,544	596,832	544,658
Operating income	54,533	51,951	345,192	321,474
Miscellaneous income (expense)	678	268	304	2,728
Interest charges	23,649	25,001	69,802	74,228
Income (loss) before income taxes	31,562	27,218	275,694	249,974
Income tax expense (benefit)	13,033	11,401	105,665	94,874
Income (loss) from continuing operations	'	15,817	'	155,100
Income from discontinued operations, net of tax	'	'	'	7,202
Gain on sale of discontinued operations, net of tax	'	5,649	'	5,649
Net income (loss)	18,529	21,466	170,029	167,951
Regulated Transmission and Storage Segment [Member]	'	'	'	'
Operating revenues	'	'	'	'
Operating revenues	87,189	74,041	232,145	196,570
Purchased gas cost	'	'	'	'
Purchased gas cost	0	0	0	0
Gross profit	87,189	74,041	232,145	196,570
Operating expenses	'	'	'	'
Operation and maintenance	23,570	17,035	57,465	48,745
Depreciation and amortization	10,281	8,676	30,223	25,756
Taxes, other than income	5,054	4,287	8,485	12,513
Total operating expenses	38,905	29,998	96,173	87,014
Operating income	48,284	44,043	135,972	109,556
Miscellaneous income (expense)	-489	-247	-2,751	-473
Interest charges	9,162	8,049	27,274	22,777
Income (loss) before income taxes	38,633	35,747	105,947	86,306
Income tax expense (benefit)	13,695	12,650	37,454	30,574
Income (loss) from continuing operations	'	23,097	'	55,732
Income from discontinued operations, net of tax	'	'	'	0
Gain on sale of discontinued operations, net of tax	'	0	'	0
Net income (loss)	24,938	23,097	68,493	55,732
Nonregulated Segment [Member]	'	'	'	'
Operating revenues	'	'	'	'
Operating revenues	465,033	421,808	1,670,437	1,250,650
Purchased gas cost	'	'	'	'
Purchased gas cost	450,220	418,548	1,599,469	1,200,624
Gross profit	14,813	3,260	70,968	50,026
Operating expenses	'	'	'	'
Operation and maintenance	9,129	11,034	19,463	24,679
Depreciation and amortization	1,132	1,085	3,395	3,073
Taxes, other than income	764	741	1,869	1,813
Total operating expenses	11,025	12,860	24,727	29,565
Operating income	3,788	-9,600	46,241	20,461
Miscellaneous income (expense)	1,018	215	1,785	1,791
Interest charges	610	392	1,840	1,687
Income (loss) before income taxes	4,196	-9,777	46,186	20,565
Income tax expense (benefit)	1,942	-4,337	18,604	8,235
Income (loss) from continuing operations	'	-5,440	'	12,330
Income from discontinued operations, net of tax	'	'	'	0
Gain on sale of discontinued operations, net of tax	'	-355	'	-355
Net income (loss)	2,254	-5,795	27,582	11,975
Intersegment Elimination [Member]	'	'	'	'
Operating revenues	'	'	'	'
Operating revenues	-127,211	-105,058	-392,926	-285,241
Purchased gas cost	'	'	'	'
Purchased gas cost	-127,077	-104,759	-392,556	-284,123
Gross profit	-134	-299	-370	-1,118
Operating expenses	'	'	'	'
Operation and maintenance	-134	-301	-370	-1,123
Depreciation and amortization	0	0	0	0
Taxes, other than income	0	0	0	0
Total operating expenses	-134	-301	-370	-1,123
Operating income	0	2	0	5
Miscellaneous income (expense)	-1,581	-703	-3,360	-2,103
Interest charges	-1,581	-701	-3,360	-2,098
Income (loss) before income taxes	0	0	0	0
Income tax expense (benefit)	0	0	0	0
Income (loss) from continuing operations	'	0	'	0
Income from discontinued operations, net of tax	'	'	'	0
Gain on sale of discontinued operations, net of tax	'	0	'	0
Net income (loss)	$0	$0	$0	$0

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (PARENTHETICALS) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Statement [Abstract]	'	'	'	'
Discontinued Operation Tax Effect Of Income Loss From Discontinued Operation During Phase Out Period	$0	$0	$0	$3,986
Discontinued Operation, Tax Effect of Income (Loss) from Disposal of Discontinued Operation	$0	$2,909	$0	$2,909

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net income (loss)	$45,721	$38,768	$266,104	$235,658
Other comprehensive income (loss), net of tax	'	'	'	'
Net unrealized holding gains (losses) on available-for-sale securities, net of tax	377	-348	2,519	-921
Amortization and unrealized gains (losses) on interest rate agreements, net of tax	-23,440	31,079	-36,545	66,852
Net unrealized gains (losses) on commodity cash flow hedges, net of tax	-2,471	-3,508	6,448	4,965
Total other comprehensive income (loss)	-25,534	27,223	-27,578	70,896
Total comprehensive income (loss)	$20,187	$65,991	$238,526	$306,554

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (PARENTHETICALS) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Other Comprehensive Income Loss Tax Portion Attributable To Parent Abstract	'	'	'	'
Unrealized holding gains (losses) on available-for-sale securities, tax	$216	($202)	$1,518	($532)
Amortization and unrealized gains (losses) on interest rate agreements, tax	-13,472	17,865	-21,005	38,427
Net unrealized gains (losses) on commodity cash flow hedging transactions, tax	($1,580)	($2,243)	$4,122	$3,174

CONDENSED_CONSOLIDATED_STATEME4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Cash Flows From Operating Activities	'	'
Net income (loss)	$266,104	$235,658
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	0	-8,203
Depreciation and amortization:	'	'
Charged to depreciation and amortization	185,731	176,737
Charged to other accounts	669	446
Other	'	'
Deferred income taxes	150,457	130,365
Other	21,587	14,460
Net Assets Liabilities From Risk Management Activities	3,158	-6,386
Net change in operating assets and liabilities	2,504	-33,502
Net cash provided by operating activities	630,210	509,575
Cash Flows From Investing Activities	'	'
Capital expenditures	-552,600	-582,473
Proceeds from Sale of Productive Assets	0	153,023
Other, net	-620	-3,139
Net cash used in investing activities	-553,220	-432,589
Cash Flows From Financing Activities	'	'
Net decrease in short-term debt	-366,602	-435,084
Net proceeds from equity offering	390,205	0
Net proceeds from issuance of long-term debt	0	493,793
Settlement of Treasury lock agreements	0	-66,626
Repayments of Long-term Debt	0	-131
Cash dividends paid	-108,806	-96,060
Repurchase of equity awards	-8,717	-5,146
Issuance of Common Stock	2,152	8
Net cash provided by (used in) financing activities	-91,768	-109,246
Net increase (decrease) in cash and cash equivalents	-14,778	-32,260
Cash and cash equivalents at beginning of period	66,199	64,239
Cash and cash equivalents at end of period	$51,421	$31,979

Nature_of_Business

Nature of Business	9 Months Ended
	Jun. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Nature of Business	'
	Nature of Business
	Atmos Energy Corporation (“Atmos Energy” or the “Company”) and our subsidiaries are engaged primarily in the regulated natural gas distribution and transmission and storage businesses as well as certain other nonregulated businesses. For the fiscal year ended September 30, 2013, our regulated businesses generated approximately 95 percent of our consolidated net income.
	Through our natural gas distribution business, we deliver natural gas through sales and transportation arrangements to approximately three million residential, commercial, public authority and industrial customers through our six regulated natural gas distribution divisions, which at June 30, 2014, covered service areas located in eight states. On April 1, 2013, we completed the divestiture of our natural gas distribution operations in Georgia, representing approximately 64,000 customers. In addition, we transport natural gas for others through our distribution system. Our regulated businesses also include our regulated pipeline and storage operations, which include the transportation of natural gas to our North Texas distribution system and the management of our underground storage facilities. Our regulated businesses are subject to federal and state regulation and/or regulation by local authorities in each of the states in which our natural gas distribution divisions operate.
	Our nonregulated businesses operate primarily in the Midwest and Southeast through various wholly-owned subsidiaries of Atmos Energy Holdings, Inc. (AEH). AEH is wholly owned by the Company and based in Houston, Texas. Through AEH, we provide natural gas management and transportation services to municipalities, natural gas distribution companies, including certain divisions of Atmos Energy, and third parties.

Unaudited_Financial_Informatio

Unaudited Financial Information	9 Months Ended
	Jun. 30, 2014
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, 2013. 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, 2013. Because of seasonal and other factors, the results of operations for the nine-month period ended June 30, 2014 are not indicative of our results of operations for the full 2014 fiscal year, which ends September 30, 2014.
	Except for the forward starting interest rate swap entered into in July 2014 as noted in Note 8, 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, 2013.
	During the second quarter of fiscal 2014, we completed our annual goodwill impairment assessment. Based on the assessment performed, we determined that our goodwill was not impaired.
	Due to the April 1, 2013 sale of our Georgia distribution operations, prior year financial results for this service area are shown in discontinued operations.
	Disclosure requirements for offsetting arrangements for financial instruments became effective for us beginning on October 1, 2013. We have presented these disclosures in Note 8. In connection with the adoption of this standard, prior-year risk management assets and liabilities have been reclassified to conform with the current-year presentation. The adoption of this standard and reclassification did not have an impact on our financial position, results of operations or cash flows.
	In April 2014, the Financial Accounting Standards Board (FASB) issued updated guidance for discontinued operations that limits discontinued operations reporting to disposals of components of an entity that represent strategic shifts that have a major effect on an entity’s operations and financial results and requires additional disclosures related to discontinued operations. This standard will become effective for us beginning on October 1, 2015. The adoption of this guidance is not expected to impact our financial position, results of operations or cash flows.
	In May 2014, the 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, a company 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 will need to use more judgment and make more estimates than under current guidance. The new standard will become effective for us beginning on October 1, 2017 and can be applied either retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. We are currently evaluating the impact this standard may have on our financial position, results of operations and cash flows.
	There were no other significant changes to our accounting policies during the nine months ended June 30, 2014 that will become applicable to the Company in future periods.
	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 substantially all of our regulatory liabilities are recorded as a component of deferred credits and other liabilities. Deferred gas costs are recorded either in other current assets or liabilities and the regulatory cost of removal obligation is reported separately.
	Significant regulatory assets and liabilities as of June 30, 2014 and September 30, 2013 included the following:
		June 30,		September 30,
		2014		2013
		(In thousands)
	Regulatory assets:
	Pension and postretirement benefit costs(1)	$	172,844	$	187,977
	Merger and integration costs, net	4,860		5,250
	Deferred gas costs	9,809		15,152
	Regulatory cost of removal asset	9,552		10,008
	Rate case costs	4,436		6,329
	Texas Rule 8.209(2)	19,349		30,364
	APT annual adjustment mechanism	5,927		5,853
	Recoverable loss on reacquired debt	19,517		21,435
	Other	4,006		4,380
		$	250,300	$	286,748
	Regulatory liabilities:
	Deferred gas costs	$	62,522	$	16,481
	Deferred franchise fees	5,918		1,689
	Regulatory cost of removal obligation	441,643		427,524
	Other	11,509		7,887
		$	521,592	$	453,581
	(1)	Includes $18.0 million and $17.4 million of pension and postretirement expense deferred pursuant to regulatory authorization.
	(2)	Texas Rule 8.209 is a Railroad Commission rule that allows for the deferral of all expenses associated with capital expenditures incurred pursuant to this rule, including the recording of interest on the deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recovered through base rates.
	Currently authorized rates do not include a return on certain of our merger and integration costs; however, we recover the amortization of these costs. Merger and integration costs, net, are generally amortized on a straight-line basis over estimated useful lives ranging up to 20 years.

Segment_Information

Segment Information	9 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Segment Information	'
	Segment Information
	We operate the Company through the following three segments:
	•	The natural gas distribution segment, which includes our regulated natural gas distribution and related sales operations,
	•	The regulated transmission and storage segment, which includes the regulated pipeline and storage operations of our Atmos Pipeline — Texas Division and
	•	The nonregulated segment, which is comprised of our nonregulated natural gas management, nonregulated natural gas transmission, storage and other services.
	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 natural gas distribution segment operations are geographically dispersed, they are reported as a single segment as each natural gas distribution division has similar economic characteristics. 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, 2013. We evaluate performance based on net income or loss of the respective operating units.
	Income statements for the three and nine month periods ended June 30, 2014 and 2013 by segment are presented in the following tables:
		Three Months Ended June 30, 2014
		Natural		Regulated			Nonregulated			Eliminations			Consolidated
		Gas		Transmission
		Distribution		and Storage
		(In thousands)
	Operating revenues from external parties	$	516,644	$	24,990		$	401,084		$	—		$	942,718
	Intersegment revenues	1,063		62,199			63,949			(127,211		)	—
		517,707		87,189			465,033			(127,211		)	942,718
	Purchased gas cost	260,042		—			450,220			(127,077		)	583,185
	Gross profit	257,665		87,189			14,813			(134		)	359,533
	Operating expenses
	Operation and maintenance	92,994		23,570			9,129			(134		)	125,559
	Depreciation and amortization	52,542		10,281			1,132			—			63,955
	Taxes, other than income	57,596		5,054			764			—			63,414
	Total operating expenses	203,132		38,905			11,025			(134		)	252,928
	Operating income	54,533		48,284			3,788			—			106,605
	Miscellaneous income (expense)	678		(489		)	1,018			(1,581		)	(374		)
	Interest charges	23,649		9,162			610			(1,581		)	31,840
	Income before income taxes	31,562		38,633			4,196			—			74,391
	Income tax expense	13,033		13,695			1,942			—			28,670
	Net income	$	18,529	$	24,938		$	2,254		$	—		$	45,721
	Capital expenditures	$	146,860	$	45,658		$	1,073		$	—		$	193,591
		Three Months Ended June 30, 2013
		Natural		Regulated			Nonregulated			Eliminations			Consolidated
		Gas		Transmission
		Distribution		and Storage
		(In thousands)
	Operating revenues from external parties	$	465,982	$	26,730		$	365,223		$	—		$	857,935
	Intersegment revenues	1,162		47,311			56,585			(105,058		)	—
		467,144		74,041			421,808			(105,058		)	857,935
	Purchased gas cost	227,649		—			418,548			(104,759		)	541,438
	Gross profit	239,495		74,041			3,260			(299		)	316,497
	Operating expenses
	Operation and maintenance	93,490		17,035			11,034			(301		)	121,258
	Depreciation and amortization	48,368		8,676			1,085			—			58,129
	Taxes, other than income	45,686		4,287			741			—			50,714
	Total operating expenses	187,544		29,998			12,860			(301		)	230,101
	Operating income (loss)	51,951		44,043			(9,600		)	2			86,396
	Miscellaneous income (expense)	268		(247		)	215			(703		)	(467		)
	Interest charges	25,001		8,049			392			(701		)	32,741
	Income (loss) from continuing operations before income taxes	27,218		35,747			(9,777		)	—			53,188
	Income tax expense (benefit)	11,401		12,650			(4,337		)	—			19,714
	Income (loss) from continuing operations	15,817		23,097			(5,440		)	—			33,474
	Gain (loss) on sale of discontinued operations, net of tax	5,649		—			(355		)	—			5,294
	Net income (loss)	$	21,466	$	23,097		$	(5,795	)	$	—		$	38,768
	Capital expenditures	$	114,606	$	78,012		$	738		$	—		$	193,356
		Nine Months Ended June 30, 2014
		Natural		Regulated			Nonregulated			Eliminations			Consolidated
		Gas		Transmission
		Distribution		and Storage
		(In thousands)
	Operating revenues from external parties	$	2,648,505	$	67,162		$	1,446,521		$	—		$	4,162,188
	Intersegment revenues	4,027		164,983			223,916			(392,926		)	—
		2,652,532		232,145			1,670,437			(392,926		)	4,162,188
	Purchased gas cost	1,710,508		—			1,599,469			(392,556		)	2,917,421
	Gross profit	942,024		232,145			70,968			(370		)	1,244,767
Operating expenses
Operation and maintenance	289,433		57,465			19,463			(370		)	365,991
Depreciation and amortization	152,113		30,223			3,395			—			185,731
Taxes, other than income	155,286		8,485			1,869			—			165,640
Total operating expenses	596,832		96,173			24,727			(370		)	717,362
Operating income	345,192		135,972			46,241			—			527,405
Miscellaneous income (expense)	304		(2,751		)	1,785			(3,360		)	(4,022		)
Interest charges	69,802		27,274			1,840			(3,360		)	95,556
Income from before income taxes	275,694		105,947			46,186			—			427,827
Income tax expense	105,665		37,454			18,604			—			161,723
Net income	$	170,029	$	68,493		$	27,582		$	—		$	266,104
Capital expenditures	$	413,921	$	137,579		$	1,100		$	—		$	552,600
	Nine Months Ended June 30, 2013
	Natural		Regulated			Nonregulated			Eliminations			Consolidated
	Gas		Transmission
	Distribution		and Storage
	(In thousands)
Operating revenues from external parties	$	2,035,712	$	65,084		$	1,100,290		$	—		$	3,201,086
Intersegment revenues	3,395		131,486			150,360			(285,241		)	—
	2,039,107		196,570			1,250,650			(285,241		)	3,201,086
Purchased gas cost	1,172,975		—			1,200,624			(284,123		)	2,089,476
Gross profit	866,132		196,570			50,026			(1,118		)	1,111,610
Operating expenses
Operation and maintenance	266,570		48,745			24,679			(1,123		)	338,871
Depreciation and amortization	146,059		25,756			3,073			—			174,888
Taxes, other than income	132,029		12,513			1,813			—			146,355
Total operating expenses	544,658		87,014			29,565			(1,123		)	660,114
Operating income	321,474		109,556			20,461			5			451,496
Miscellaneous income (expense)	2,728		(473		)	1,791			(2,103		)	1,943
Interest charges	74,228		22,777			1,687			(2,098		)	96,594
Income from continuing operations before income taxes	249,974		86,306			20,565			—			356,845
Income tax expense	94,874		30,574			8,235			—			133,683
Income from continuing operations	155,100		55,732			12,330			—			223,162
Income from discontinued operations, net of tax	7,202		—			—			—			7,202
Gain (loss) on sale of discontinued operations, net of tax	5,649		—			(355		)	—			5,294
Net income	$	167,951	$	55,732		$	11,975		$	—		$	235,658
Capital expenditures	$	391,942	$	189,051		$	1,480		$	—		$	582,473
Balance sheet information at June 30, 2014 and September 30, 2013 by segment is presented in the following tables:
	30-Jun-14
	Natural		Regulated			Nonregulated			Eliminations			Consolidated
	Gas		Transmission
	Distribution		and Storage
	(In thousands)
ASSETS
Property, plant and equipment, net	$	5,036,007	$	1,366,928		$	58,515		$	—		$	6,461,450
Investment in subsidiaries	933,660		—			(2,096		)	(931,564		)	—
Current assets
Cash and cash equivalents	17,042		—			34,379			—			51,421
Assets from risk management activities	36,438		—			7,918			—			44,356
Other current assets	461,644		15,813			581,221			(379,812		)	678,866
Intercompany receivables	775,175		—			—			(775,175		)	—
Total current assets	1,290,299		15,813			623,518			(1,154,987		)	774,643
Goodwill	574,190		132,462			34,711			—			741,363
Noncurrent assets from risk management activities	20,708		—			5,109			—			25,817
Deferred charges and other assets	325,035		22,474			6,407			—			353,916
	$	8,179,899	$	1,537,677		$	726,164		$	(2,086,551	)	$	8,357,189
CAPITALIZATION AND LIABILITIES
Shareholders’ equity	$	3,116,685	$	464,914		$	468,746		$	(933,660	)	$	3,116,685
Long-term debt	1,955,907		—			—			—			1,955,907
Total capitalization	5,072,592		464,914			468,746			(933,660		)	5,072,592
Current liabilities
Current maturities of long-term debt	500,000		—			—			—			500,000
Short-term debt	357,000		—			—			(357,000		)	—
Liabilities from risk management activities	609		—			—			—			609
Other current liabilities	477,726		14,837			183,241			(20,716		)	655,088
Intercompany payables	—		717,134			58,041			(775,175		)	—
Total current liabilities	1,335,335		731,971			241,282			(1,152,891		)	1,155,697
Deferred income taxes	988,737		338,350			14,207			—			1,341,294
Noncurrent liabilities from risk management activities	7,024		—			—			—			7,024
Regulatory cost of removal obligation	391,785		—			—			—			391,785
Pension and postretirement liabilities	347,344		—			—			—			347,344
Deferred credits and other liabilities	37,082		2,442			1,929			—			41,453
	$	8,179,899	$	1,537,677		$	726,164		$	(2,086,551	)	$	8,357,189
	30-Sep-13
	Natural		Regulated			Nonregulated			Eliminations			Consolidated
	Gas		Transmission
	Distribution		and Storage
	(In thousands)
ASSETS
Property, plant and equipment, net	$	4,719,873	$	1,249,767		$	61,015		$	—		$	6,030,655
Investment in subsidiaries	831,136		—			(2,096		)	(829,040		)	—
Current assets
Cash and cash equivalents	4,237		—			61,962			—			66,199
Assets from risk management activities	1,837		—			10,129			—			11,966
Other current assets	428,366		11,709			452,126			(293,233		)	598,968
Intercompany receivables	783,738		—			—			(783,738		)	—
Total current assets	1,218,178		11,709			524,217			(1,076,971		)	677,133
Goodwill	574,190		132,462			34,711			—			741,363
Noncurrent assets from risk management activities	109,354		—			—			—			109,354
Deferred charges and other assets	347,687		19,227			8,849			—			375,763
	$	7,800,418	$	1,413,165		$	626,696		$	(1,906,011	)	$	7,934,268
CAPITALIZATION AND LIABILITIES
Shareholders’ equity	$	2,580,409	$	396,421		$	434,715		$	(831,136	)	$	2,580,409
Long-term debt	2,455,671		—			—			—			2,455,671
Total capitalization	5,036,080		396,421			434,715			(831,136		)	5,036,080
Current liabilities
Current maturities of long-term debt	—		—			—			—			—
Short-term debt	645,984		—			—			(278,000		)	367,984
Liabilities from risk management activities	1,543		—			—			—			1,543
Other current liabilities	491,681		20,288			110,306			(13,316		)	608,959
Intercompany payables	—		712,768			70,970			(783,738		)	—
Total current liabilities	1,139,208		733,056			181,276			(1,075,054		)	978,486
Deferred income taxes	871,360		283,554			8,960			179			1,164,053
Regulatory cost of removal obligation	359,299		—			—			—			359,299
Pension and postretirement liabilities	358,787		—			—			—			358,787
Deferred credits and other liabilities	35,684		134			1,745			—			37,563
	$	7,800,418	$	1,413,165		$	626,696		$	(1,906,011	)	$	7,934,268

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Jun. 30, 2014
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, 2014 and 2013 are calculated as follows:
		Three Months Ended				Nine Months Ended
		June 30				June 30
		2014		2013		2014		2013
		(In thousands, except per share amounts)
	Basic Earnings Per Share from continuing operations
	Income from continuing operations	$	45,721	$	33,474	$	266,104	$	223,162
	Less: Income from continuing operations allocated to participating securities	107		91		674		760
	Income from continuing operations available to common shareholders	$	45,614	$	33,383	$	265,430	$	222,402
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Income from continuing operations per share — Basic	$	0.45	$	0.37	$	2.78	$	2.46
	Basic Earnings Per Share from discontinued operations
	Income from discontinued operations	$	—	$	5,294	$	—	$	12,496
	Less: Income from discontinued operations allocated to participating securities	—		14		—		43
	Income from discontinued operations available to common shareholders	$	—	$	5,280	$	—	$	12,453
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Income from discontinued operations per share — Basic	$	—	$	0.06	$	—	$	0.14
	Net income per share — Basic	$	0.45	$	0.43	$	2.78	$	2.6
		Three Months Ended				Nine Months Ended
		June 30				June 30
		2014		2013		2014		2013
		(In thousands, except per share amounts)
	Diluted Earnings Per Share from continuing operations
	Income from continuing operations available to common shareholders	$	45,614	$	33,383	$	265,430	$	222,402
	Effect of dilutive stock options and other shares	—		—		4		5
	Income from continuing operations available to common shareholders	$	45,614	$	33,383	$	265,434	$	222,407
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Additional dilutive stock options and other shares	883		947		884		948
	Diluted weighted average shares outstanding	101,150		91,550		96,339		91,445
	Income from continuing operations per share — Diluted	$	0.45	$	0.36	$	2.76	$	2.43
	Diluted Earnings Per Share from discontinued operations
	Income from discontinued operations available to common shareholders	$	—	$	5,280	$	—	$	12,453
	Effect of dilutive stock options and other shares	—		—		—		—
	Income from discontinued operations available to common shareholders	$	—	$	5,280	$	—	$	12,453
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Additional dilutive stock options and other shares	883		947		884		948
	Diluted weighted average shares outstanding	101,150		91,550		96,339		91,445
	Income from discontinued operations per share — Diluted	$	—	$	0.06	$	—	$	0.14
	Net income per share — Diluted	$	0.45	$	0.42	$	2.76	$	2.57
	There were no out-of-the-money stock options excluded from the computation of diluted earnings per share for the three and nine months ended June 30, 2014 and 2013 as their exercise price was less than the average market price of the common stock during those periods.
	2014 Equity Offering
	On February 18, 2014, we completed the public offering of 9,200,000 shares of our common stock including the underwriters’ exercise of their overallotment option of 1,200,000 shares under our existing shelf registration statement. The offering was priced at $44.00 and generated net proceeds of $390.2 million, which were used to repay short-term debt outstanding under our $950 million commercial paper program, to fund infrastructure spending primarily to enhance the safety and reliability of our system and for general corporate purposes.
	2011 Share Repurchase Program
	We did not repurchase any shares during the nine months ended June 30, 2014 and 2013 under our 2011 share repurchase program.

Debt

Debt	9 Months Ended
	Jun. 30, 2014
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, 2013. Except as noted below, there were no material changes in the terms of our debt instruments during the nine months ended June 30, 2014.
	Long-term debt
	Long-term debt at June 30, 2014 and September 30, 2013 consisted of the following:
		30-Jun-14		30-Sep-13
		(In thousands)
	Unsecured 4.95% Senior Notes, due October 2014	$	500,000	$	500,000
	Unsecured 6.35% Senior Notes, due 2017	250,000		250,000
	Unsecured 8.50% Senior Notes, due 2019	450,000		450,000
	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
	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
	Total long-term debt	2,460,000		2,460,000
	Less:
	Original issue discount on unsecured senior notes and debentures	4,093		4,329
	Current maturities	500,000		—
		$	1,955,907	$	2,455,671
	Short-term debt
	Our short-term debt is utilized to fund ongoing working capital needs, such as our seasonal requirements for gas supply, general corporate liquidity and capital expenditures. 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.
	We currently finance our short-term borrowing requirements through a combination of a $950 million commercial paper program, four committed revolving credit facilities and one uncommitted revolving credit facility with third-party lenders. These facilities provide approximately $1 billion of working capital funding. At June 30, 2014, there were no short-term debt borrowings outstanding. At September 30, 2013, there was a total of $368.0 million outstanding under our commercial paper program.
	Regulated Operations
	We fund our regulated operations as needed, primarily through our commercial paper program and three committed revolving credit facilities with third-party lenders that provide approximately $985 million of working capital funding, including a five-year $950 million unsecured facility with an accordion feature, which, if utilized would increase the borrowing capacity to $1.2 billion, a $25 million unsecured facility and a $10 million unsecured revolving credit facility, which is used primarily to issue letters of credit. Due to outstanding letters of credit, the total amount available to us under our $10 million revolving credit facility was $4.1 million at June 30, 2014.
	In addition to these third-party facilities, our regulated operations have a $500 million intercompany revolving credit facility with AEH, which bears interest at the lower of (i) the Eurodollar rate under the five-year revolving credit facility or (ii) the rate outstanding under the commercial paper program. Applicable state regulatory commissions have approved our use of this facility through December 31, 2014.
	Nonregulated Operations
	Atmos Energy Marketing, LLC (AEM), which is wholly owned by AEH, had two $25 million 364-day bilateral credit facilities that expired in December 2013. In December 2013, the $25 million 364-day uncommitted bilateral facility was extended to December 2014. In January 2014, this facility was amended to temporarily increase the amount available to $50 million to address the increase in volumes and prices driven by colder than normal weather this past winter-heating season.  In June 2014, the facility was further amended to extend the temporary increase for 90 days through September 28, 2014. The maximum available under the facility will return to $25 million after the additional 90-day period expires. The $25 million committed bilateral facility was replaced with a $15 million committed 364-day bilateral credit facility in December 2013. These facilities are used primarily to issue letters of credit. Due to outstanding letters of credit, the total amount available to us under these bilateral credit facilities was $52.3 million at June 30, 2014.
	AEH has a $500 million intercompany demand credit facility with AEC. This facility bears interest at a rate equal to the one-month LIBOR rate plus 3.00 percent or (ii) the rate for AEM's borrowings under its committed credit facility plus 0.75 percent. Applicable state regulatory commissions have approved our use of this facility through December 31, 2014.
	Shelf Registration
	We filed a shelf registration statement with the Securities and Exchange Commission (SEC) on March 28, 2013 that originally permitted us to issue a total of $1.75 billion in common stock and/or debt securities. On February 18, 2014, we completed the public offering of 9,200,000 shares of our common stock, which generated net proceeds of $390.2 million. As of June 30, 2014, $1.35 billion of securities remained available for issuance under the shelf registration statement until March 28, 2016.
	Debt Covenants
	The availability of funds under our regulated 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, 2014, our total-debt-to-total-capitalization ratio, as defined in the agreements, was 46 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.
	In addition to these financial covenants, our credit facilities and 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, 2014. 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.

Interim_Pension_and_Other_Post

Interim Pension and Other Postretirement Benefit Plan Information	9 Months Ended
	Jun. 30, 2014
General Discussion of Pension and Other Postretirement Benefits [Abstract]	'
Interim Pension and Postretirement Benefit Plans	'
	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, 2014 and 2013 are presented in the following table. Most of these costs are recoverable through our gas distribution rates; however, a portion of these costs is capitalized into our gas distribution rate base. The remaining costs are recorded as a component of operation and maintenance expense. On October 2, 2013, due to the retirement of one of our executive officers, we recognized a settlement loss of $4.5 million associated with our Supplemental Executive Benefits Plan (SEBP). In association with his retirement, on October 2, 2013, we made a $16.8 million benefit payment from the SEBP. On April 1, 2013, due to the retirement of certain executives, we recognized a curtailment loss of $3.2 million associated with our SEBP and revalued the net periodic pension cost for the remainder of fiscal 2013. The revaluation of the net periodic pension cost resulted in an increase in the discount rate, effective April 1, 2013, to 4.21 percent, which reduced our net periodic pension cost by approximately $0.1 million for the remainder of the fiscal year. All other actuarial assumptions remained the same.
		Three Months Ended June 30
		Pension Benefits								Other Benefits
		2014				2013				2014			2013
		(In thousands)
	Components of net periodic pension cost:
	Service cost	$	4,738			$	5,194			$	4,196		$	4,700
	Interest cost	6,824				6,019				3,987			3,241
	Expected return on assets	(5,901		)		(5,739		)		(1,291		)	(997		)
	Amortization of transition obligation	—				—				69			271
	Amortization of prior service credit	(34		)		(35		)		(363		)	(363		)
	Amortization of actuarial loss	3,931				5,432				158			1,049
	Settlement loss	—				3,161				—			—
	Net periodic pension cost	$	9,558			$	14,032			$	6,756		$	7,901
		Nine Months Ended June 30
		Pension Benefits								Other Benefits
		2014				2013				2014			2013
		(In thousands)
	Components of net periodic pension cost:
	Service cost	$	14,214			$	15,599			$	12,588		$	14,100
	Interest cost	20,472				18,067				11,963			9,723
	Expected return on assets	(17,702		)		(17,216		)		(3,875		)	(2,991		)
	Amortization of transition obligation	—				—				205			811
	Amortization of prior service credit	(102		)		(106		)		(1,088		)	(1,088		)
	Amortization of actuarial loss	11,793				16,555				474			3,147
	Settlement loss	4,539				3,161				—			—
	Net periodic pension cost	$	33,214			$	36,060			$	20,267		$	23,702
	The assumptions used to develop our net periodic pension cost for the three and nine months ended June 30, 2014 and 2013 are as follows:
		Supplemental Executive Benefit Plans						Pension Benefits					Other Benefits
		2014			2013			2014			2013		2014			2013
	Discount rate	4.95	%		4.21	%		4.95	%		4.04	%	4.95	%		4.04	%
	Rate of compensation increase	3.5	%		3.5	%		3.5	%		3.5	%	N/A			N/A
	Expected return on plan assets	N/A			N/A			7.25	%		7.75	%	4.6	%		4.7	%
	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 plans as of January 1, 2014. During the first nine months of fiscal 2014, we contributed $27.1 million to our defined benefit plans and we do not anticipate making any contributions during the fourth quarter of fiscal 2014.
	We contributed $18.1 million to our other post-retirement benefit plans during the nine months ended June 30, 2014. We expect to contribute a total of approximately $20 million to $25 million to these plans during all of fiscal 2014.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Litigation and Environmental Matters
	With respect to the specific litigation and environmental-related matters or claims that were disclosed in Note 10 to the financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2013, except as noted below, there were no material changes in the status of such litigation and environmental-related matters or claims during the nine months ended June 30, 2014.
	Kentucky Litigation
	Beginning in April 2009, Atmos Energy and two subsidiaries of AEH, AEM and Atmos Gathering Company, LLC (AGC) (collectively, the Atmos Entities), were involved in a lawsuit filed in the Circuit Court of Edmonson County, Kentucky related to our Park City Gathering Project. The dispute which gave rise to the litigation involves the amount of royalties due from a third party producer to landowners (who own the mineral rights) for natural gas produced from the landowners’ properties. The third party producer was operating pursuant to leases between the landowners and certain investors/working interest owners. The third party producer filed a petition in bankruptcy, which was subsequently dismissed due to the lack of meaningful assets to reorganize or liquidate.
	Although certain Atmos Energy companies entered into contracts with the third party producer to gather, treat and ultimately sell natural gas produced from the landowners’ properties, no Atmos Energy company had a contractual relationship with the landowners or the investors/working interest owners. After the lawsuit was filed, the landowners were successful in terminating for non-payment of royalties the leases related to the production of natural gas from their properties. Subsequent to termination, the investors/working interest owners under such leases filed additional claims against us for the termination of the leases.
	During the trial, the landowners and the investors/working interest owners requested an award of compensatory damages plus punitive damages against us. On December 17, 2010, the jury returned a verdict in favor of the landowners and investor/working interest owners and awarded compensatory damages of $3.8 million and punitive damages of $27.5 million payable by Atmos Energy and the two AEH subsidiaries.
	A hearing was held on February 28, 2011 to hear a number of motions, including a motion to dismiss the jury verdict and a motion for a new trial. The motions to dismiss the jury verdict and for a new trial were denied. However, the total punitive damages award was reduced from $27.5 million to $24.7 million. On October 17, 2011, we filed our brief of appellants with the Kentucky Court of Appeals, appealing the verdict of the trial court. The appellees in this case subsequently filed their appellees’ brief with the Court of Appeals on January 16, 2012, with our reply brief being filed with the Court of Appeals on March 19, 2012. Oral arguments were held in the case on August 27, 2012.
	In an opinion handed down on January 25, 2013, the Court of Appeals overturned the $28.5 million jury verdict returned against the Atmos Entities. In a unanimous decision by a three-judge panel, the Court of Appeals reversed the claims asserted by the landowners and investors/working interest owners. The Court of Appeals concluded that all of such claims that the Atmos Entities appealed should have been dismissed by the trial court as a matter of law. The Court of Appeals let stand the jury verdict on one claim that Atmos Energy and our subsidiaries chose not to appeal, which was a trespass claim. The jury had awarded a total of $10,000 in compensatory damages plus accrued interest to one landowner on that claim. The claim was paid on February 18, 2013. The Court of Appeals vacated all of the other damages awarded by the jury and remanded the case to the trial court for a new trial, solely on the issue of whether punitive damages should be awarded to that landowner and, if so, in what amount.
	The investors/working interest owners, on February 25, 2013, and the landowners, on March 19, 2013, then each filed with the Supreme Court of Kentucky, separate motions for discretionary review of the opinion of the Court of Appeals. We filed responses to the motions. The Kentucky Supreme Court denied the motions for discretionary review on February 12, 2014 and the decision of the Court of Appeals became final on February 21, 2014.  We had previously accrued what we believed to be an adequate amount for the anticipated resolution of this matter. This accrual was reversed during the second fiscal quarter of fiscal 2014 as the appellate process in this case had been completed. Atmos Energy had also filed a motion with the trial court, the Circuit Court of Edmonson County, Kentucky, on March 10, 2014, seeking a ruling that the remaining landowner was not entitled to any punitive damages on the sole remaining claim of trespass.  On May 19, 2014, the Edmonson County Circuit Court entered judgment dismissing any claim for punitive damages relating to the trespass claim. There was no appeal of this judgment. The lawsuit in Edmonson County has now been fully and finally resolved.
	In addition, in a related matter, on July 12, 2011, the Atmos Entities filed a lawsuit in the United States District Court, Western District of Kentucky, Atmos Energy Corporation et al.vs. Resource Energy Technologies, LLC and Robert Thorpe and John F. Charles, against the third party producer and its affiliates to recover all costs, including attorneys’ fees, incurred by the Atmos Entities, which are associated with the defense and appeal of the case discussed above as well as for all damages awarded to the plaintiffs in such case against the Atmos Entities. The total amount of damages being claimed in the lawsuit is “open-ended” since the appellate process and related costs are ongoing. This lawsuit is based upon the indemnification provisions agreed to by the third party producer in favor of Atmos Gathering that are contained in an agreement entered into between AGC and the third party producer in May 2009. The defendants filed a motion to dismiss the case on August 25, 2011, with Atmos Energy filing a brief in response to such motion on September 19, 2011. On March 27, 2012 the court denied the motion to dismiss. Atmos Energy filed a motion for partial summary judgment against the defendants with the District Court on July 15, 2014, with a ruling by the Court still pending. This case is scheduled for trial beginning October 6, 2014.
	Tennessee Business License Tax
	Atmos Energy, through its affiliate, AEM, has been involved in a dispute with the Tennessee Department of Revenue (TDOR) regarding sales business tax audits over a period of several years. The cumulative assessment approximated $12 million as of March 31, 2014, which AEM challenged. We had previously accrued in prior years what we believed to be an adequate amount for the anticipated resolution of this matter. With respect to certain issues, AEM and the TDOR filed competing Partial Motions for Summary Judgment with the Chancery Court. On August 2, 2013, the Chancery Court granted the TDOR's Partial Motion for Summary Judgment and denied AEM's Partial Motion for Summary Judgment. An agreed order of dismissal with prejudice between     AEM and TDOR was approved by the Chancery Court and entered on May 2, 2014, whereby AEM agreed to pay $6.2 million to TDOR to resolve all business tax-related liabilities outstanding through September 2014. The State of Tennessee also passed related legislation, effective July 1, 2014, that should help minimize any disputes over this type of sales business tax in the future.
	We are a party to 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
	AEH has commitments to purchase physical quantities of natural gas under contracts indexed to the forward NYMEX strip or fixed price contracts. At June 30, 2014, AEH was committed to purchase 105.2 Bcf within one year, 18.0 Bcf within one to three years and 0.6 Bcf after three years under indexed contracts. AEH is committed to purchase 10.0 Bcf within one year under fixed price contracts with prices ranging from $3.66 to $6.36 per Mcf. Purchases under these contracts totaled $383.2 million and $340.9 million for the three months ended June 30, 2014 and 2013 and $1,354.5 million and $958.2 million for the nine months ended June 30, 2014 and 2013.
	Our natural gas distribution divisions, except for our Mid-Tex Division, 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 maintains 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 market and fixed prices. The estimated commitments under these contracts as of June 30, 2014 are as follows (in thousands):
	2014	$	51,946
	2015	234,824
	2016	167,747
	2017	67,185
	Thereafter	—
		$	521,702
	Our nonregulated segment maintains long-term contracts related to storage and transportation. The estimated contractual demand fees for contracted storage and transportation under these contracts are detailed in our Annual Report on Form 10-K for the fiscal year ended September 30, 2013. There were no material changes to the estimated storage and transportation fees for the nine months ended June 30, 2014.
	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, 2014, rate cases were in progress in our Kansas, Colorado and Virginia service areas, annual rate filing mechanisms were in progress in Louisiana and Mid-Tex and an infrastructure program filing was in progress in Virginia. These regulatory proceedings are discussed in further detail below in Management’s Discussion and Analysis — Recent Ratemaking Developments.

Financial_Instruments

Financial Instruments	9 Months Ended
	Jun. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Financial Instruments	'
	Financial Instruments
	We use financial instruments to mitigate commodity price risk and interest rate risk. The objectives and strategies for using financial instruments have been tailored to our regulated and nonregulated businesses. The accounting for these financial instruments is fully described in Note 2 to the consolidated financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2013. During the nine months ended June 30, 2014 there were no changes in our objectives, strategies and accounting for these financial instruments. Currently, we utilize financial instruments in our natural gas distribution and nonregulated segments. We currently do not manage commodity price risk with financial instruments in our regulated transmission and storage segment.
	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.
	Regulated Commodity Risk Management Activities
	Although our purchased gas cost adjustment mechanisms essentially insulate our natural gas distribution segment from commodity price risk, 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.
	Our natural gas distribution gas supply department is responsible for executing this segment’s commodity risk management activities in conformity with regulatory requirements. In jurisdictions where we are permitted to mitigate commodity price risk through financial instruments, the relevant regulatory authorities may establish the level of heating season gas purchases that can be hedged. Historically, if the regulatory authority does not establish this level, we seek to hedge between 25 and 50 percent of anticipated heating season gas purchases using financial instruments. For the 2013-2014 heating season (generally October through March), in the jurisdictions where we are permitted to utilize financial instruments, we hedged approximately 32 percent, or 24.6 Bcf of the winter flowing gas requirements. We have not designated these financial instruments as hedges for accounting purposes.
	The costs associated with the gains and losses arising from the use of financial instruments to mitigate commodity price risk are included in our purchased gas cost adjustment mechanisms in accordance with regulatory requirements. Therefore, changes in the fair value of these financial instruments are initially recorded as a component of deferred gas costs and 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 in accordance with applicable authoritative accounting guidance. Accordingly, there is no earnings impact on our natural gas distribution segment as a result of the use of financial instruments.
	Nonregulated Commodity Risk Management Activities
	Our nonregulated operations aggregate and purchase gas supply, arrange transportation and/or storage logistics and ultimately deliver gas to our customers at competitive prices. To provide these services, we utilize proprietary and customer-owned transportation and storage assets to provide the various services our customers request. In an effort to offset the demand fees paid to contract for storage capacity and to maximize the value of this capacity, AEH sells financial instruments to earn a gross profit margin through the arbitrage of pricing differences in various locations and by recognizing pricing differences that occur over time.
	As a result of these activities, our nonregulated segment is exposed to risks associated with changes in the market price of natural gas. We manage 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. Future contracts provide the right, but not the obligation, to buy or sell the commodity at a fixed price. Option contracts provide the right, but not the requirement, to buy or sell the commodity at a fixed price. Swap contracts require receipt of payment for the commodity based on the difference between a fixed price and the market price on the settlement date.
	We use financial instruments, designated as cash flow hedges of anticipated purchases and sales at index prices, to mitigate the commodity price risk in our nonregulated operations associated with deliveries under fixed-priced forward contracts to deliver gas to customers. These financial instruments have maturity dates ranging from one to 46 months. We use financial instruments, designated as fair value hedges, to hedge our natural gas inventory used in asset optimization activities in our nonregulated segment.
	Our nonregulated operations also use storage swaps and futures to capture additional storage arbitrage opportunities that arise subsequent to the execution of the original fair value hedge associated with our physical natural gas inventory, basis swaps to insulate and protect the economic value of our fixed price and storage books and various over-the-counter and exchange-traded options. These financial instruments have not been designated 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, 2014, we had forward starting interest rate swaps to effectively fix the Treasury yield component associated with the anticipated issuance of $500 million and $250 million unsecured senior notes in fiscal 2015 and fiscal 2017, at 3.129% and 3.37%, which we designated as cash flow hedges at the time the agreements were executed. In April, May and July 2014, we entered into forward starting interest rate swaps to effectively fix the Treasury yield component associated with $325 million of the anticipated issuance of $450 million unsecured senior notes in fiscal 2019 at 3.91%, which we designated as cash flow hedges at the time the agreements were executed. Accordingly, unrealized gains and losses associated with the forward starting interest rate swaps are being recorded as a component of accumulated other comprehensive income (loss). When the forward starting interest rate swaps settle, the realized gain or loss will be recorded as a component of accumulated other comprehensive income (loss) and recognized as a component of interest expense over the life of the related financing arrangement. Hedge ineffectiveness to the extent incurred is reported as a component of interest expense.
	In prior years, we entered into Treasury lock agreements to fix the Treasury yield component of the interest cost of financing various issuances of long-term debt and senior notes. The gains and losses realized upon settlement of these Treasury locks were recorded as a component of accumulated other comprehensive income (loss) when they were settled and are being recognized as a component of interest expense over the life of the associated notes from the date of settlement. As of June 30, 2014, the remaining amortization periods for the settled Treasury locks extended through fiscal 2043.
	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, 2014, 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, 2014, we had net long/(short) commodity contracts outstanding in the following quantities:
	Contract Type		Hedge Designation		Natural Gas			Nonregulated
					Distribution
					Quantity (MMcf)
	Commodity contracts		Fair Value		—			(9,255	)
			Cash Flow		—			29,930
			Not designated		20,826			63,168
					20,826			83,843
	Financial Instruments on the Balance Sheet
	The following tables present the fair value and balance sheet classification of our financial instruments by operating segment as of June 30, 2014 and September 30, 2013. 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 the counterparties.
				Natural Gas Distribution								Nonregulated
		Balance Sheet Location		Assets				Liabilities				Assets				Liabilities
				(In thousands)
	30-Jun-14
	Designated As Hedges:
	Commodity contracts	Other current assets /		$	—			$	—			$	8,442			$	(3,741	)
		Other current liabilities
	Interest rate contracts	Other current assets /		33,183				—				—				—
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		—				—				730				(1,421		)
		Deferred credits and other liabilities
	Interest rate contracts	Deferred charges and other assets /		20,455				(6,849		)		—				—
		Deferred credits and other liabilities
	Total			53,638				(6,849		)		9,172				(5,162		)
	Not Designated As Hedges:
	Commodity contracts	Other current assets /		3,255				(609		)		45,242				(51,715		)
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		253				(175		)		20,476				(14,675		)
		Deferred credits and other liabilities
	Total			3,508				(784		)		65,718				(66,390		)
	Gross Financial Instruments			57,146				(7,633		)		74,890				(71,552		)
	Gross Amounts Offset on Consolidated Balance Sheet:
	Contract netting			—				—				(69,782		)		69,782
	Net Financial Instruments			57,146				(7,633		)		5,108				(1,770		)
	Cash collateral			—				—				7,919				1,770
	Net Assets/Liabilities from Risk Management Activities			$	57,146			$	(7,633	)		$	13,027			$	—
				Natural Gas Distribution								Nonregulated
		Balance Sheet Location		Assets				Liabilities				Assets				Liabilities
				(In thousands)
	30-Sep-13
	Designated As Hedges:
	Commodity contracts	Other current assets /		$	—			$	—			$	9,094			$	(12,173	)
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		—				—				416				(1,639		)
		Deferred credits and other liabilities
Interest rate contracts	Deferred charges and other assets /		107,512				—				—				—
	Deferred credits and other liabilities
Total			107,512				—				9,510				(13,812		)
Not Designated As Hedges:
Commodity contracts	Other current assets /		1,837				(1,543		)		65,388				(70,876		)
	Other current liabilities
Commodity contracts	Deferred charges and other assets /		1,842				—				40,982				(45,892		)
	Deferred credits and other liabilities
Total			3,679				(1,543		)		106,370				(116,768		)
Gross Financial Instruments			111,191				(1,543		)		115,880				(130,580		)
Gross Amounts Offset on Consolidated Balance Sheet:
Contract netting			—				—				(115,875		)		115,875
Net Financial Instruments			111,191				(1,543		)		5				(14,705		)
Cash collateral			—				—				10,124				14,705
Net Assets/Liabilities from Risk Management Activities			$	111,191			$	(1,543	)		$	10,129			$	—
Impact of Financial Instruments on the Income Statement
Hedge ineffectiveness for our nonregulated segment is recorded as a component of unrealized gross profit and primarily results from differences in the location and timing of the derivative instrument and the hedged item. Hedge ineffectiveness could materially affect our results of operations for the reported period. For the three months ended June 30, 2014 and 2013 we recognized a loss arising from fair value and cash flow hedge ineffectiveness of $0.1 million and $0.4 million. For the nine months ended June 30, 2014 and 2013, we recognized a gain arising from fair value and cash flow hedge ineffectiveness of $1.3 million and $17.3 million. Additional information regarding ineffectiveness recognized in the income statement is included in the tables below.
Fair Value Hedges
The impact of our nonregulated commodity contracts designated as fair value hedges and the related hedged item on our condensed consolidated income statement for the three and nine months ended June 30, 2014 and 2013 is presented below.
	Three Months Ended
	June 30
	2014				2013
	(In thousands)
Commodity contracts	$	1,991			$	14,453
Fair value adjustment for natural gas inventory designated as the hedged item	(2,258		)		(15,143		)
Total increase in purchased gas cost	$	(267	)		$	(690	)
The (increase) decrease in purchased gas cost is comprised of the following:
Basis ineffectiveness	$	817			$	(2,361	)
Timing ineffectiveness	(1,084		)		1,671
	$	(267	)		$	(690	)
	Nine Months Ended
	June 30
	2014				2013
	(In thousands)
Commodity contracts	$	(2,983	)		$	3,921
Fair value adjustment for natural gas inventory designated as the hedged item	4,071				13,261
Total decrease in purchased gas cost	$	1,088			$	17,182
The (increase) decrease in purchased gas cost is comprised of the following:
Basis ineffectiveness	$	(382	)		$	(1,143	)
Timing ineffectiveness	1,470				18,325
	$	1,088			$	17,182
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. As the commodity contract nears the settlement date, spot-to-forward price differences should converge, which should reduce or eliminate the impact of this ineffectiveness on purchased gas cost. To the extent that the Company’s natural gas inventory does not qualify as a hedged item in a fair-value hedge, or has not been designated as such, the natural gas inventory is valued at the lower of cost or market.
Cash Flow Hedges
The impact of cash flow hedges on our condensed consolidated income statements for the three and nine months ended June 30, 2014 and 2013 is presented below. Note that this presentation does not reflect the financial impact arising from the hedged physical transaction. Therefore, this presentation is not indicative of the economic gross profit we realized when the underlying physical and financial transactions were settled.
	Three Months Ended June 30, 2014
	Natural				Nonregulated				Consolidated
	Gas
	Distribution
	(In thousands)
Gain reclassified from AOCI for effective portion of commodity contracts	$	—			$	4,209			$	4,209
Gain arising from ineffective portion of commodity contracts	—				179				179
Total impact on purchased gas cost	—				4,388				4,388
Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(1,057		)		—				(1,057		)
Total Impact from Cash Flow Hedges	$	(1,057	)		$	4,388			$	3,331
	Three Months Ended June 30, 2013
	Natural				Nonregulated				Consolidated
	Gas
	Distribution
	(In thousands)
Gain reclassified from AOCI for effective portion of commodity contracts	$	—			$	558			$	558
Gain arising from ineffective portion of commodity contracts	—				260				260
Total impact on purchased gas cost	—				818				818
Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(1,057		)		—				(1,057		)
Total Impact from Cash Flow Hedges	$	(1,057	)		$	818			$	(239	)
	Nine Months Ended June 30, 2014
	Natural				Nonregulated				Consolidated
	Gas
	Distribution
	(In thousands)
Gain reclassified from AOCI for effective portion of commodity contracts	$	—			$	8,783			$	8,783
Gain arising from ineffective portion of commodity contracts	—				203				203
Total impact on purchased gas cost	—				8,986				8,986
Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(3,172		)		—				(3,172		)
Total Impact from Cash Flow Hedges	$	(3,172	)		$	8,986			$	5,814
	Nine Months Ended June 30, 2013
	Natural Gas				Nonregulated				Consolidated
	Distribution
	(In thousands)
Loss reclassified from AOCI for effective portion of commodity contracts	$	—			$	(9,802	)		$	(9,802	)
Gain arising from ineffective portion of commodity contracts	—				158				158
Total impact on purchased gas cost	—				(9,644		)		(9,644		)
Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(2,432		)		—				(2,432		)
Total Impact from Cash Flow Hedges	$	(2,432	)		$	(9,644	)		$	(12,076	)
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, 2014 and 2013. 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
	June 30								June 30
	2014				2013				2014				2013
	(In thousands)
Increase (decrease) in fair value:
Interest rate agreements	$	(24,111	)		$	30,408			$	(38,559	)		$	65,308
Forward commodity contracts	96				(3,168		)		11,805				(1,015		)
Recognition of (gains) losses in earnings due to settlements:
Interest rate agreements	671				671				2,014				1,544
Forward commodity contracts	(2,567		)		(340		)		(5,357		)		5,980
Total other comprehensive income (loss) from hedging, net of tax(1)	$	(25,911	)		$	27,571			$	(30,097	)		$	71,817
(1)	Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.
Deferred gains (losses) recorded in accumulated other comprehensive income (AOCI) associated with our interest rate agreements are recognized in earnings as they are amortized over the terms of the underlying debt instruments, while deferred gains (losses) associated with commodity contracts are recognized in earnings upon settlement. The following amounts, net of deferred taxes, represent the expected recognition in earnings of the deferred gains (losses) recorded in AOCI associated with our financial instruments, based upon the fair values of these financial instruments as of June 30, 2014. 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				Commodity				Total
	Agreements				Contracts
	(In thousands)
Next twelve months	$	(1,317	)		$	2,407			$	1,090
Thereafter	(27,033		)		(435		)		(27,468		)
Total(1)	$	(28,350	)		$	1,972			$	(26,378	)
(1)	Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.
Financial Instruments Not Designated as Hedges
The impact of financial instruments that have not been designated as hedges on our condensed consolidated income statements for the three months ended June 30, 2014 and 2013 was a decrease in gross profit of $0.6 million and $8.4 million. For the nine months ended June 30, 2014 and 2013 gross profit decreased by $10.7 million and $1.7 million. Note that this presentation does not reflect the expected gains or losses arising from the underlying physical transactions associated with these financial instruments. Therefore, this presentation is not indicative of the economic gross profit we realized when the underlying physical and financial transactions were settled.
As discussed above, financial instruments used in our natural gas distribution segment are not designated as hedges. However, there is no earnings impact on our natural gas 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.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income	9 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Accumulated Other Comprehensive Income	'
	Accumulated Other Comprehensive Income
	We record deferred gains (losses) in accumulated other comprehensive income (AOCI) related to available-for-sale securities, interest rate agreement cash flow hedges and 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.
		Available-			Interest			Commodity			Total
		for-Sale			Rate			Contracts
		Securities			Agreement			Cash Flow
					Cash Flow			Hedges
					Hedges
		(In thousands)
	30-Sep-13	$	5,448		$	37,906		$	(4,476	)	$	38,878
	Other comprehensive income (loss) before reclassifications	3,212			(38,559		)	11,805			(23,542		)
	Amounts reclassified from accumulated other comprehensive income	(693		)	2,014			(5,357		)	(4,036		)
	Net current-period other comprehensive income (loss)	2,519			(36,545		)	6,448			(27,578		)
	30-Jun-14	$	7,967		$	1,361		$	1,972		$	11,300
		Available-			Interest			Commodity			Total
		for-Sale			Rate			Contracts
		Securities			Agreement			Cash Flow
					Cash Flow			Hedges
					Hedges
		(In thousands)
	30-Sep-12	$	5,661		$	(44,273	)	$	(8,995	)	$	(47,607	)
	Other comprehensive income (loss) before reclassifications	449			65,308			(1,015		)	64,742
	Amounts reclassified from accumulated other comprehensive income	(1,370		)	1,544			5,980			6,154
	Net current-period other comprehensive income (loss)	(921		)	66,852			4,965			70,896
	30-Jun-13	$	4,740		$	22,579		$	(4,030	)	$	23,289
	The following tables detail reclassifications out of AOCI for the three and nine months ended June 30, 2014 and 2013. Amounts in parentheses below indicate decreases to net income in the statement of income.
		Three Months Ended June 30, 2014
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	733		Operation and maintenance expense
		733			Total before tax
		(267		)	Tax expense
		$	466		Net of tax
	Cash flow hedges
	Interest rate agreements	$	(1,057	)	Interest charges
	Commodity contracts	4,209			Purchased gas cost
		3,152			Total before tax
		(1,256		)	Tax expense
		$	1,896		Net of tax
	Total reclassifications	$	2,362		Net of tax
		Three Months Ended June 30, 2013
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	(531	)	Operation and maintenance expense
		(531		)	Total before tax
		193			Tax benefit
		$	(338	)	Net of tax
	Cash flow hedges
	Interest rate agreements	$	(1,057	)	Interest charges
	Commodity contracts	558			Purchased gas cost
		(499		)	Total before tax
		168			Tax benefit
		$	(331	)	Net of tax
	Total reclassifications	$	(669	)	Net of tax
		Nine Months Ended June 30, 2014
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in  the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	1,091		Operation and maintenance expense
	1,091			Total before tax
	(398		)	Tax expense
	$	693		Net of tax
Cash flow hedges
Interest rate agreements	$	(3,172	)	Interest charges
Commodity contracts	8,783			Purchased gas cost
	5,611			Total before tax
	(2,268		)	Tax expense
	$	3,343		Net of tax
Total reclassifications	$	4,036		Net of tax
	Nine Months Ended June 30, 2013
Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in  the
	Accumulated Other			Statement of Income
	Comprehensive Income
	(In thousands)
Available-for-sale securities	$	2,158		Operation and maintenance expense
	2,158			Total before tax
	(788		)	Tax expense
	$	1,370		Net of tax
Cash flow hedges
Interest rate agreements	$	(2,432	)	Interest charges
Commodity contracts	(9,803		)	Purchased gas cost
	(12,235		)	Total before tax
	4,711			Tax benefit
	$	(7,524	)	Net of tax
Total reclassifications	$	(6,154	)	Net of tax

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Jun. 30, 2014
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, 2013. During the nine months ended June 30, 2014, 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 6 to the financial statements in our Annual Report on Form 10-K for the fiscal year ending September 30, 2013.
	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, 2014 and September 30, 2013. Assets and liabilities are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement.
		Quoted		Significant		Significant			Netting and			30-Jun-14
		Prices in		Other		Other			Cash
		Active		Observable		Unobservable			Collateral(2)
		Markets		Inputs		Inputs
		(Level 1)		(Level 2)(1)		(Level 3)
		(In thousands)
	Assets:
	Financial instruments
	Natural gas distribution segment	$	—	$	57,146	$	—		$	—		$	57,146
	Nonregulated segment	3		74,887		—			(61,863		)	13,027
	Total financial instruments	3		132,033		—			(61,863		)	70,173
	Hedged portion of gas stored underground	39,191		—		—			—			39,191
	Available-for-sale securities
	Money market funds	—		1,959		—			—			1,959
	Registered investment companies	45,554		—		—			—			45,554
	Bonds	—		33,397		—			—			33,397
	Total available-for-sale securities	45,554		35,356		—			—			80,910
	Total assets	$	84,748	$	167,389	$	—		$	(61,863	)	$	190,274
	Liabilities:
	Financial instruments
	Natural gas distribution segment	$	—	$	7,633	$	—		$	—		$	7,633
	Nonregulated segment	108		71,444		—			(71,552		)	—
	Total liabilities	$	108	$	79,077	$	—		$	(71,552	)	$	7,633
		Quoted		Significant		Significant			Netting and			30-Sep-13
		Prices in		Other		Other			Cash
		Active		Observable		Unobservable			Collateral(3)
		Markets		Inputs		Inputs
		(Level 1)		(Level 2)(1)		(Level 3)
		(In thousands)
	Assets:
	Financial instruments
	Natural gas distribution segment	$	—	$	111,191	$	—		$	—		$	111,191
	Nonregulated segment	745		115,135		—			(105,751		)	10,129
	Total financial instruments	745		226,326		—			(105,751		)	121,320
	Hedged portion of gas stored underground	44,758		—		—			—			44,758
	Available-for-sale securities
	Money market funds	—		4,428		—			—			4,428
	Registered investment companies	40,094		—		—			—			40,094
	Bonds	—		28,160		—			—			28,160
	Total available-for-sale securities	40,094		32,588		—			—			72,682
	Total assets	$	85,597	$	258,914	$	—		$	(105,751	)	$	238,760
	Liabilities:
	Financial instruments
	Natural gas distribution segment	$	—	$	1,543	$	—		$	—		$	1,543
	Nonregulated segment	158		130,422		—			(130,580		)	—
	Total liabilities	$	158	$	131,965	$	—		$	(130,580	)	$	1,543
	(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 which are valued at cost.
	(2)	This column reflects adjustments to our gross financial instrument assets and liabilities to reflect netting permitted under our master netting agreements and the relevant authoritative accounting literature. In addition, as of June 30, 2014, we had $9.7 million of cash held in margin accounts to collateralize certain financial instruments. Of this amount, $1.8 million was used to offset current risk management liabilities under master netting arrangements and the remaining $7.9 million is classified as current risk management assets.
	(3)	This column reflects adjustments to our gross financial instrument assets and liabilities to reflect netting permitted under our master netting agreements and the relevant authoritative accounting literature. In addition, as of September 30, 2013 we had $24.8 million of cash held in margin accounts to collateralize certain financial instruments. Of this amount, $14.7 million was used to offset current and noncurrent risk management liabilities under master netting arrangements and the remaining $10.1 million is classified as current risk management assets.
	Available-for-sale securities are comprised of the following:
		Amortized		Gross		Gross			Fair
		Cost		Unrealized		Unrealized			Value
				Gain		Loss
		(In thousands)
	As of June 30, 2014
	Domestic equity mutual funds	$	27,983	$	10,274	$	—		$	38,257
	Foreign equity mutual funds	5,092		2,205		—			7,297
Bonds	33,180		220		(3		)	33,397
Money market funds	1,959		—		—			1,959
	$	68,214	$	12,699	$	(3	)	$	80,910
As of September 30, 2013
Domestic equity mutual funds	$	27,043	$	7,476	$	(23	)	$	34,496
Foreign equity mutual funds	4,536		1,062		—			5,598
Bonds	28,016		168		(24		)	28,160
Money market funds	4,428		—		—			4,428
	$	64,023	$	8,706	$	(47	)	$	72,682
At June 30, 2014 and September 30, 2013, our available-for-sale securities included $47.5 million and $44.5 million related to assets held in separate rabbi trusts for our supplemental executive benefit plans. At June 30, 2014, we maintained investments in bonds that have contractual maturity dates ranging from July 2014 through December 2019. During the nine months ended June 30, 2014 and 2013, we recognized gains of $1.1 million and $2.2 million on the sale of certain assets in the rabbi trusts.
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, 2014 and September 30, 2013:
	30-Jun-14		30-Sep-13
	(In thousands)
Carrying Amount	$	2,460,000	$	2,460,000
Fair Value	$	2,795,188	$	2,676,487

Concentration_of_Credit_Risk

Concentration of Credit Risk	9 Months Ended
	Jun. 30, 2014
Risks and Uncertainties [Abstract]	'
Concentration of Credit Risk	'
	Concentration of Credit Risk
	Information regarding our concentration of credit risk is disclosed in Note 15 to the financial statements in our Annual Report on Form 10-K for the fiscal year ended September 30, 2013. During the nine months ended June 30, 2014, there were no material changes in our concentration of credit risk.

Discontinued_Operations

Discontinued Operations	9 Months Ended
	Jun. 30, 2014
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued Operations	'
	Discontinued Operations
	On April 1, 2013, we completed the sale of substantially all of our natural gas distribution assets and certain related nonregulated assets located in Georgia to Liberty Energy (Georgia) Corp., an affiliate of Algonquin Power & Utilities Corp. for a cash price of approximately $153 million. In connection with the sale, we recognized a net of tax gain of $5.3 million.
	For the three months ended June 30, 2013, net income from discontinued operations includes the aforementioned gain on sale, while for the nine months ended June 30, 2013, net income from discontinued operations includes the operating results of our Georgia operations and the gain on sale. As required under generally accepted accounting principles, the operating results from our discontinued Georgia operations have been aggregated and reported on the condensed consolidated statements of income as income from discontinued operations, net of income tax. Expenses related to general corporate overhead and interest expense allocated to their operations are not included in discontinued operations.
	The table below sets forth statement of income data related to discontinued operations. At June 30, 2014 and September 30, 2013 we did not have any assets or liabilities held for sale.
		Three Months Ended				Nine Months Ended
		June 30				June 30
		2014		2013		2014		2013
		(In thousands)
	Operating revenues	$	—	$	—	$	—	$	37,962
	Purchased gas cost	—		—		—		21,464
	Gross profit	—		—		—		16,498
	Operating expenses	—		—		—		5,858
	Operating income	—		—		—		10,640
	Other nonoperating income	—		—		—		548
	Income from discontinued operations before income taxes	—		—		—		11,188
	Income tax expense	—		—		—		3,986
	Income from discontinued operations	—		—		—		7,202
	Gain on sale of discontinued operations, net of tax	—		5,294		—		5,294
	Net income from discontinued operations	$	—	$	5,294	$	—	$	12,496

Accounting_Policies_Policy

Accounting Policies (Policy)	9 Months Ended
	Jun. 30, 2014
Accounting Policies [Abstract]	'
Regulatory assets and liabilities	'Regulatory assets and liabilitiesAccounting 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 substantially all of our regulatory liabilities are recorded as a component of deferred credits and other liabilities. Deferred gas costs are recorded either in other current assets or liabilities and the regulatory cost of removal obligation is reported separately.
Segment Reporting	'
	Segment Information
	We operate the Company through the following three segments:
	•	The natural gas distribution segment, which includes our regulated natural gas distribution and related sales operations,
	•	The regulated transmission and storage segment, which includes the regulated pipeline and storage operations of our Atmos Pipeline — Texas Division and
	•	The nonregulated segment, which is comprised of our nonregulated natural gas management, nonregulated natural gas transmission, storage and other services.
	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 natural gas distribution segment operations are geographically dispersed, they are reported as a single segment as each natural gas distribution division has similar economic characteristics. 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, 2013. We evaluate performance based on net income or loss of the respective operating units.
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, 2013. During the nine months ended June 30, 2014, there were no changes in these methods.

Unaudited_Financial_Informatio1

Unaudited Financial Information (Table)	9 Months Ended
	Jun. 30, 2014
Regulatory Assets And Liabilities Table [Abstract]	'
Regulatory assets and liabilities table	'
	Significant regulatory assets and liabilities as of June 30, 2014 and September 30, 2013 included the following:
		June 30,		September 30,
		2014		2013
		(In thousands)
	Regulatory assets:
	Pension and postretirement benefit costs(1)	$	172,844	$	187,977
	Merger and integration costs, net	4,860		5,250
	Deferred gas costs	9,809		15,152
	Regulatory cost of removal asset	9,552		10,008
	Rate case costs	4,436		6,329
	Texas Rule 8.209(2)	19,349		30,364
	APT annual adjustment mechanism	5,927		5,853
	Recoverable loss on reacquired debt	19,517		21,435
	Other	4,006		4,380
		$	250,300	$	286,748
	Regulatory liabilities:
	Deferred gas costs	$	62,522	$	16,481
	Deferred franchise fees	5,918		1,689
	Regulatory cost of removal obligation	441,643		427,524
	Other	11,509		7,887
		$	521,592	$	453,581
	(1)	Includes $18.0 million and $17.4 million of pension and postretirement expense deferred pursuant to regulatory authorization.
	(2)	Texas Rule 8.209 is a Railroad Commission rule that allows for the deferral of all expenses associated with capital expenditures incurred pursuant to this rule, including the recording of interest on the deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recovered through base rates.

Segment_Information_Table

Segment Information (Table)	9 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Schedule of Segment Reporting Information, by Segment	'
	Income statements for the three and nine month periods ended June 30, 2014 and 2013 by segment are presented in the following tables:
		Three Months Ended June 30, 2014
		Natural		Regulated			Nonregulated			Eliminations			Consolidated
		Gas		Transmission
		Distribution		and Storage
		(In thousands)
	Operating revenues from external parties	$	516,644	$	24,990		$	401,084		$	—		$	942,718
	Intersegment revenues	1,063		62,199			63,949			(127,211		)	—
		517,707		87,189			465,033			(127,211		)	942,718
	Purchased gas cost	260,042		—			450,220			(127,077		)	583,185
	Gross profit	257,665		87,189			14,813			(134		)	359,533
	Operating expenses
	Operation and maintenance	92,994		23,570			9,129			(134		)	125,559
	Depreciation and amortization	52,542		10,281			1,132			—			63,955
	Taxes, other than income	57,596		5,054			764			—			63,414
	Total operating expenses	203,132		38,905			11,025			(134		)	252,928
	Operating income	54,533		48,284			3,788			—			106,605
	Miscellaneous income (expense)	678		(489		)	1,018			(1,581		)	(374		)
	Interest charges	23,649		9,162			610			(1,581		)	31,840
	Income before income taxes	31,562		38,633			4,196			—			74,391
	Income tax expense	13,033		13,695			1,942			—			28,670
	Net income	$	18,529	$	24,938		$	2,254		$	—		$	45,721
	Capital expenditures	$	146,860	$	45,658		$	1,073		$	—		$	193,591
		Three Months Ended June 30, 2013
		Natural		Regulated			Nonregulated			Eliminations			Consolidated
		Gas		Transmission
		Distribution		and Storage
		(In thousands)
	Operating revenues from external parties	$	465,982	$	26,730		$	365,223		$	—		$	857,935
	Intersegment revenues	1,162		47,311			56,585			(105,058		)	—
		467,144		74,041			421,808			(105,058		)	857,935
	Purchased gas cost	227,649		—			418,548			(104,759		)	541,438
	Gross profit	239,495		74,041			3,260			(299		)	316,497
	Operating expenses
	Operation and maintenance	93,490		17,035			11,034			(301		)	121,258
	Depreciation and amortization	48,368		8,676			1,085			—			58,129
	Taxes, other than income	45,686		4,287			741			—			50,714
	Total operating expenses	187,544		29,998			12,860			(301		)	230,101
	Operating income (loss)	51,951		44,043			(9,600		)	2			86,396
	Miscellaneous income (expense)	268		(247		)	215			(703		)	(467		)
	Interest charges	25,001		8,049			392			(701		)	32,741
	Income (loss) from continuing operations before income taxes	27,218		35,747			(9,777		)	—			53,188
	Income tax expense (benefit)	11,401		12,650			(4,337		)	—			19,714
	Income (loss) from continuing operations	15,817		23,097			(5,440		)	—			33,474
	Gain (loss) on sale of discontinued operations, net of tax	5,649		—			(355		)	—			5,294
	Net income (loss)	$	21,466	$	23,097		$	(5,795	)	$	—		$	38,768
	Capital expenditures	$	114,606	$	78,012		$	738		$	—		$	193,356
		Nine Months Ended June 30, 2014
		Natural		Regulated			Nonregulated			Eliminations			Consolidated
		Gas		Transmission
		Distribution		and Storage
		(In thousands)
	Operating revenues from external parties	$	2,648,505	$	67,162		$	1,446,521		$	—		$	4,162,188
	Intersegment revenues	4,027		164,983			223,916			(392,926		)	—
		2,652,532		232,145			1,670,437			(392,926		)	4,162,188
	Purchased gas cost	1,710,508		—			1,599,469			(392,556		)	2,917,421
	Gross profit	942,024		232,145			70,968			(370		)	1,244,767
	Operating expenses
	Operation and maintenance	289,433		57,465			19,463			(370		)	365,991
	Depreciation and amortization	152,113		30,223			3,395			—			185,731
	Taxes, other than income	155,286		8,485			1,869			—			165,640
	Total operating expenses	596,832		96,173			24,727			(370		)	717,362
	Operating income	345,192		135,972			46,241			—			527,405
Miscellaneous income (expense)	304		(2,751		)	1,785			(3,360		)	(4,022		)
Interest charges	69,802		27,274			1,840			(3,360		)	95,556
Income from before income taxes	275,694		105,947			46,186			—			427,827
Income tax expense	105,665		37,454			18,604			—			161,723
Net income	$	170,029	$	68,493		$	27,582		$	—		$	266,104
Capital expenditures	$	413,921	$	137,579		$	1,100		$	—		$	552,600
	Nine Months Ended June 30, 2013
	Natural		Regulated			Nonregulated			Eliminations			Consolidated
	Gas		Transmission
	Distribution		and Storage
	(In thousands)
Operating revenues from external parties	$	2,035,712	$	65,084		$	1,100,290		$	—		$	3,201,086
Intersegment revenues	3,395		131,486			150,360			(285,241		)	—
	2,039,107		196,570			1,250,650			(285,241		)	3,201,086
Purchased gas cost	1,172,975		—			1,200,624			(284,123		)	2,089,476
Gross profit	866,132		196,570			50,026			(1,118		)	1,111,610
Operating expenses
Operation and maintenance	266,570		48,745			24,679			(1,123		)	338,871
Depreciation and amortization	146,059		25,756			3,073			—			174,888
Taxes, other than income	132,029		12,513			1,813			—			146,355
Total operating expenses	544,658		87,014			29,565			(1,123		)	660,114
Operating income	321,474		109,556			20,461			5			451,496
Miscellaneous income (expense)	2,728		(473		)	1,791			(2,103		)	1,943
Interest charges	74,228		22,777			1,687			(2,098		)	96,594
Income from continuing operations before income taxes	249,974		86,306			20,565			—			356,845
Income tax expense	94,874		30,574			8,235			—			133,683
Income from continuing operations	155,100		55,732			12,330			—			223,162
Income from discontinued operations, net of tax	7,202		—			—			—			7,202
Gain (loss) on sale of discontinued operations, net of tax	5,649		—			(355		)	—			5,294
Net income	$	167,951	$	55,732		$	11,975		$	—		$	235,658
Capital expenditures	$	391,942	$	189,051		$	1,480		$	—		$	582,473
Balance sheet information at June 30, 2014 and September 30, 2013 by segment is presented in the following tables:
	30-Jun-14
	Natural		Regulated			Nonregulated			Eliminations			Consolidated
	Gas		Transmission
	Distribution		and Storage
	(In thousands)
ASSETS
Property, plant and equipment, net	$	5,036,007	$	1,366,928		$	58,515		$	—		$	6,461,450
Investment in subsidiaries	933,660		—			(2,096		)	(931,564		)	—
Current assets
Cash and cash equivalents	17,042		—			34,379			—			51,421
Assets from risk management activities	36,438		—			7,918			—			44,356
Other current assets	461,644		15,813			581,221			(379,812		)	678,866
Intercompany receivables	775,175		—			—			(775,175		)	—
Total current assets	1,290,299		15,813			623,518			(1,154,987		)	774,643
Goodwill	574,190		132,462			34,711			—			741,363
Noncurrent assets from risk management activities	20,708		—			5,109			—			25,817
Deferred charges and other assets	325,035		22,474			6,407			—			353,916
	$	8,179,899	$	1,537,677		$	726,164		$	(2,086,551	)	$	8,357,189
CAPITALIZATION AND LIABILITIES
Shareholders’ equity	$	3,116,685	$	464,914		$	468,746		$	(933,660	)	$	3,116,685
Long-term debt	1,955,907		—			—			—			1,955,907
Total capitalization	5,072,592		464,914			468,746			(933,660		)	5,072,592
Current liabilities
Current maturities of long-term debt	500,000		—			—			—			500,000
Short-term debt	357,000		—			—			(357,000		)	—
Liabilities from risk management activities	609		—			—			—			609
Other current liabilities	477,726		14,837			183,241			(20,716		)	655,088
Intercompany payables	—		717,134			58,041			(775,175		)	—
Total current liabilities	1,335,335		731,971			241,282			(1,152,891		)	1,155,697
Deferred income taxes	988,737		338,350			14,207			—			1,341,294
Noncurrent liabilities from risk management activities	7,024		—			—			—			7,024
Regulatory cost of removal obligation	391,785		—			—			—			391,785
Pension and postretirement liabilities	347,344		—			—			—			347,344
Deferred credits and other liabilities	37,082		2,442			1,929			—			41,453
	$	8,179,899	$	1,537,677		$	726,164		$	(2,086,551	)	$	8,357,189
	30-Sep-13
	Natural		Regulated			Nonregulated			Eliminations			Consolidated
	Gas		Transmission
	Distribution		and Storage
	(In thousands)
ASSETS
Property, plant and equipment, net	$	4,719,873	$	1,249,767		$	61,015		$	—		$	6,030,655
Investment in subsidiaries	831,136		—			(2,096		)	(829,040		)	—
Current assets
Cash and cash equivalents	4,237		—			61,962			—			66,199
Assets from risk management activities	1,837		—			10,129			—			11,966
Other current assets	428,366		11,709			452,126			(293,233		)	598,968
Intercompany receivables	783,738		—			—			(783,738		)	—
Total current assets	1,218,178		11,709			524,217			(1,076,971		)	677,133
Goodwill	574,190		132,462			34,711			—			741,363
Noncurrent assets from risk management activities	109,354		—			—			—			109,354
Deferred charges and other assets	347,687		19,227			8,849			—			375,763
	$	7,800,418	$	1,413,165		$	626,696		$	(1,906,011	)	$	7,934,268
CAPITALIZATION AND LIABILITIES
Shareholders’ equity	$	2,580,409	$	396,421		$	434,715		$	(831,136	)	$	2,580,409
Long-term debt	2,455,671		—			—			—			2,455,671
Total capitalization	5,036,080		396,421			434,715			(831,136		)	5,036,080
Current liabilities
Current maturities of long-term debt	—		—			—			—			—
Short-term debt	645,984		—			—			(278,000		)	367,984
Liabilities from risk management activities	1,543		—			—			—			1,543
Other current liabilities	491,681		20,288			110,306			(13,316		)	608,959
Intercompany payables	—		712,768			70,970			(783,738		)	—
Total current liabilities	1,139,208		733,056			181,276			(1,075,054		)	978,486
Deferred income taxes	871,360		283,554			8,960			179			1,164,053
Regulatory cost of removal obligation	359,299		—			—			—			359,299
Pension and postretirement liabilities	358,787		—			—			—			358,787
Deferred credits and other liabilities	35,684		134			1,745			—			37,563
	$	7,800,418	$	1,413,165		$	626,696		$	(1,906,011	)	$	7,934,268

Earnings_Per_Share_Table

Earnings Per Share (Table)	9 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Earnings per share table	'
	Basic and diluted earnings per share for the three and nine months ended June 30, 2014 and 2013 are calculated as follows:
		Three Months Ended				Nine Months Ended
		June 30				June 30
		2014		2013		2014		2013
		(In thousands, except per share amounts)
	Basic Earnings Per Share from continuing operations
	Income from continuing operations	$	45,721	$	33,474	$	266,104	$	223,162
	Less: Income from continuing operations allocated to participating securities	107		91		674		760
	Income from continuing operations available to common shareholders	$	45,614	$	33,383	$	265,430	$	222,402
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Income from continuing operations per share — Basic	$	0.45	$	0.37	$	2.78	$	2.46
	Basic Earnings Per Share from discontinued operations
	Income from discontinued operations	$	—	$	5,294	$	—	$	12,496
	Less: Income from discontinued operations allocated to participating securities	—		14		—		43
	Income from discontinued operations available to common shareholders	$	—	$	5,280	$	—	$	12,453
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Income from discontinued operations per share — Basic	$	—	$	0.06	$	—	$	0.14
	Net income per share — Basic	$	0.45	$	0.43	$	2.78	$	2.6
		Three Months Ended				Nine Months Ended
		June 30				June 30
		2014		2013		2014		2013
		(In thousands, except per share amounts)
	Diluted Earnings Per Share from continuing operations
	Income from continuing operations available to common shareholders	$	45,614	$	33,383	$	265,430	$	222,402
	Effect of dilutive stock options and other shares	—		—		4		5
	Income from continuing operations available to common shareholders	$	45,614	$	33,383	$	265,434	$	222,407
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Additional dilutive stock options and other shares	883		947		884		948
	Diluted weighted average shares outstanding	101,150		91,550		96,339		91,445
	Income from continuing operations per share — Diluted	$	0.45	$	0.36	$	2.76	$	2.43
	Diluted Earnings Per Share from discontinued operations
	Income from discontinued operations available to common shareholders	$	—	$	5,280	$	—	$	12,453
	Effect of dilutive stock options and other shares	—		—		—		—
	Income from discontinued operations available to common shareholders	$	—	$	5,280	$	—	$	12,453
	Basic weighted average shares outstanding	100,267		90,603		95,455		90,497
	Additional dilutive stock options and other shares	883		947		884		948
	Diluted weighted average shares outstanding	101,150		91,550		96,339		91,445
	Income from discontinued operations per share — Diluted	$	—	$	0.06	$	—	$	0.14
	Net income per share — Diluted	$	0.45	$	0.42	$	2.76	$	2.57

Debt_Table

Debt (Table)	9 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Components of Debt	'
	Long-term debt at June 30, 2014 and September 30, 2013 consisted of the following:
		30-Jun-14		30-Sep-13
		(In thousands)
	Unsecured 4.95% Senior Notes, due October 2014	$	500,000	$	500,000
	Unsecured 6.35% Senior Notes, due 2017	250,000		250,000
	Unsecured 8.50% Senior Notes, due 2019	450,000		450,000
	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
	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
	Total long-term debt	2,460,000		2,460,000
	Less:
	Original issue discount on unsecured senior notes and debentures	4,093		4,329
	Current maturities	500,000		—
		$	1,955,907	$	2,455,671

Interim_Pension_and_Other_Post1

Interim Pension and Other Postretirement Benefits (Table)	9 Months Ended
	Jun. 30, 2014
General Discussion of Pension and Other Postretirement Benefits [Abstract]	'
Components of net periodic pension cost table	'
	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, 2014 and 2013 are presented in the following table. Most of these costs are recoverable through our gas distribution rates; however, a portion of these costs is capitalized into our gas distribution rate base. The remaining costs are recorded as a component of operation and maintenance expense. On October 2, 2013, due to the retirement of one of our executive officers, we recognized a settlement loss of $4.5 million associated with our Supplemental Executive Benefits Plan (SEBP). In association with his retirement, on October 2, 2013, we made a $16.8 million benefit payment from the SEBP. On April 1, 2013, due to the retirement of certain executives, we recognized a curtailment loss of $3.2 million associated with our SEBP and revalued the net periodic pension cost for the remainder of fiscal 2013. The revaluation of the net periodic pension cost resulted in an increase in the discount rate, effective April 1, 2013, to 4.21 percent, which reduced our net periodic pension cost by approximately $0.1 million for the remainder of the fiscal year. All other actuarial assumptions remained the same.
		Three Months Ended June 30
		Pension Benefits								Other Benefits
		2014				2013				2014			2013
		(In thousands)
	Components of net periodic pension cost:
	Service cost	$	4,738			$	5,194			$	4,196		$	4,700
	Interest cost	6,824				6,019				3,987			3,241
	Expected return on assets	(5,901		)		(5,739		)		(1,291		)	(997		)
	Amortization of transition obligation	—				—				69			271
	Amortization of prior service credit	(34		)		(35		)		(363		)	(363		)
	Amortization of actuarial loss	3,931				5,432				158			1,049
	Settlement loss	—				3,161				—			—
	Net periodic pension cost	$	9,558			$	14,032			$	6,756		$	7,901
		Nine Months Ended June 30
		Pension Benefits								Other Benefits
		2014				2013				2014			2013
		(In thousands)
	Components of net periodic pension cost:
	Service cost	$	14,214			$	15,599			$	12,588		$	14,100
	Interest cost	20,472				18,067				11,963			9,723
	Expected return on assets	(17,702		)		(17,216		)		(3,875		)	(2,991		)
	Amortization of transition obligation	—				—				205			811
	Amortization of prior service credit	(102		)		(106		)		(1,088		)	(1,088		)
	Amortization of actuarial loss	11,793				16,555				474			3,147
	Settlement loss	4,539				3,161				—			—
	Net periodic pension cost	$	33,214			$	36,060			$	20,267		$	23,702
Schedule of assumptions used table text block	'
	The assumptions used to develop our net periodic pension cost for the three and nine months ended June 30, 2014 and 2013 are as follows:
		Supplemental Executive Benefit Plans						Pension Benefits					Other Benefits
		2014			2013			2014			2013		2014			2013
	Discount rate	4.95	%		4.21	%		4.95	%		4.04	%	4.95	%		4.04	%
	Rate of compensation increase	3.5	%		3.5	%		3.5	%		3.5	%	N/A			N/A
	Expected return on plan assets	N/A			N/A			7.25	%		7.75	%	4.6	%		4.7	%

Commitments_and_Contingencies_

Commitments and Contingencies Commitments and Contingencies (Tables)	9 Months Ended
	Jun. 30, 2014
Commitments and Contingencies [Abstract]	'
Long-term Purchase Commitment [Table Text Block]	'
	Our Mid-Tex Division maintains 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 market and fixed prices. The estimated commitments under these contracts as of June 30, 2014 are as follows (in thousands):
	2014	$	51,946
	2015	234,824
	2016	167,747
	2017	67,185
	Thereafter	—
		$	521,702

Financial_Instruments_Table

Financial Instruments (Table)	9 Months Ended
	Jun. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Oustanding commodity contracts volumes table	'
	As of June 30, 2014, we had net long/(short) commodity contracts outstanding in the following quantities:
	Contract Type		Hedge Designation		Natural Gas			Nonregulated
					Distribution
					Quantity (MMcf)
	Commodity contracts		Fair Value		—			(9,255	)
			Cash Flow		—			29,930
			Not designated		20,826			63,168
					20,826			83,843
Financial instruments on the balance sheet	'
				Natural Gas Distribution								Nonregulated
		Balance Sheet Location		Assets				Liabilities				Assets				Liabilities
				(In thousands)
	30-Sep-13
	Designated As Hedges:
	Commodity contracts	Other current assets /		$	—			$	—			$	9,094			$	(12,173	)
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		—				—				416				(1,639		)
		Deferred credits and other liabilities
	Interest rate contracts	Deferred charges and other assets /		107,512				—				—				—
		Deferred credits and other liabilities
	Total			107,512				—				9,510				(13,812		)
	Not Designated As Hedges:
	Commodity contracts	Other current assets /		1,837				(1,543		)		65,388				(70,876		)
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		1,842				—				40,982				(45,892		)
		Deferred credits and other liabilities
	Total			3,679				(1,543		)		106,370				(116,768		)
	Gross Financial Instruments			111,191				(1,543		)		115,880				(130,580		)
	Gross Amounts Offset on Consolidated Balance Sheet:
	Contract netting			—				—				(115,875		)		115,875
	Net Financial Instruments			111,191				(1,543		)		5				(14,705		)
	Cash collateral			—				—				10,124				14,705
	Net Assets/Liabilities from Risk Management Activities			$	111,191			$	(1,543	)		$	10,129			$	—
	The following tables present the fair value and balance sheet classification of our financial instruments by operating segment as of June 30, 2014 and September 30, 2013. 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 the counterparties.
				Natural Gas Distribution								Nonregulated
		Balance Sheet Location		Assets				Liabilities				Assets				Liabilities
				(In thousands)
	30-Jun-14
	Designated As Hedges:
	Commodity contracts	Other current assets /		$	—			$	—			$	8,442			$	(3,741	)
		Other current liabilities
	Interest rate contracts	Other current assets /		33,183				—				—				—
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		—				—				730				(1,421		)
		Deferred credits and other liabilities
	Interest rate contracts	Deferred charges and other assets /		20,455				(6,849		)		—				—
		Deferred credits and other liabilities
	Total			53,638				(6,849		)		9,172				(5,162		)
	Not Designated As Hedges:
	Commodity contracts	Other current assets /		3,255				(609		)		45,242				(51,715		)
		Other current liabilities
	Commodity contracts	Deferred charges and other assets /		253				(175		)		20,476				(14,675		)
		Deferred credits and other liabilities
	Total			3,508				(784		)		65,718				(66,390		)
	Gross Financial Instruments			57,146				(7,633		)		74,890				(71,552		)
	Gross Amounts Offset on Consolidated Balance Sheet:
	Contract netting			—				—				(69,782		)		69,782
	Net Financial Instruments			57,146				(7,633		)		5,108				(1,770		)
	Cash collateral			—				—				7,919				1,770
	Net Assets/Liabilities from Risk Management Activities			$	57,146			$	(7,633	)		$	13,027			$	—
Fair value hedges table	'
	The impact of our nonregulated commodity contracts designated as fair value hedges and the related hedged item on our condensed consolidated income statement for the three and nine months ended June 30, 2014 and 2013 is presented below.
		Three Months Ended
		June 30
		2014				2013
		(In thousands)
	Commodity contracts	$	1,991			$	14,453
	Fair value adjustment for natural gas inventory designated as the hedged item	(2,258		)		(15,143		)
	Total increase in purchased gas cost	$	(267	)		$	(690	)
	The (increase) decrease in purchased gas cost is comprised of the following:
	Basis ineffectiveness	$	817			$	(2,361	)
	Timing ineffectiveness	(1,084		)		1,671
		$	(267	)		$	(690	)
		Nine Months Ended
		June 30
		2014				2013
		(In thousands)
	Commodity contracts	$	(2,983	)		$	3,921
	Fair value adjustment for natural gas inventory designated as the hedged item	4,071				13,261
	Total decrease in purchased gas cost	$	1,088			$	17,182
	The (increase) decrease in purchased gas cost is comprised of the following:
	Basis ineffectiveness	$	(382	)		$	(1,143	)
	Timing ineffectiveness	1,470				18,325
		$	1,088			$	17,182
Cash flow hedges	'
	The impact of cash flow hedges on our condensed consolidated income statements for the three and nine months ended June 30, 2014 and 2013 is presented below. Note that this presentation does not reflect the financial impact arising from the hedged physical transaction. Therefore, this presentation is not indicative of the economic gross profit we realized when the underlying physical and financial transactions were settled.
		Three Months Ended June 30, 2014
		Natural				Nonregulated				Consolidated
		Gas
		Distribution
		(In thousands)
	Gain reclassified from AOCI for effective portion of commodity contracts	$	—			$	4,209			$	4,209
	Gain arising from ineffective portion of commodity contracts	—				179				179
	Total impact on purchased gas cost	—				4,388				4,388
	Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(1,057		)		—				(1,057		)
	Total Impact from Cash Flow Hedges	$	(1,057	)		$	4,388			$	3,331
		Three Months Ended June 30, 2013
		Natural				Nonregulated				Consolidated
		Gas
		Distribution
		(In thousands)
	Gain reclassified from AOCI for effective portion of commodity contracts	$	—			$	558			$	558
	Gain arising from ineffective portion of commodity contracts	—				260				260
	Total impact on purchased gas cost	—				818				818
	Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(1,057		)		—				(1,057		)
	Total Impact from Cash Flow Hedges	$	(1,057	)		$	818			$	(239	)
		Nine Months Ended June 30, 2014
		Natural				Nonregulated				Consolidated
		Gas
		Distribution
		(In thousands)
	Gain reclassified from AOCI for effective portion of commodity contracts	$	—			$	8,783			$	8,783
	Gain arising from ineffective portion of commodity contracts	—				203				203
	Total impact on purchased gas cost	—				8,986				8,986
	Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(3,172		)		—				(3,172		)
	Total Impact from Cash Flow Hedges	$	(3,172	)		$	8,986			$	5,814
		Nine Months Ended June 30, 2013
		Natural Gas				Nonregulated				Consolidated
		Distribution
		(In thousands)
	Loss reclassified from AOCI for effective portion of commodity contracts	$	—			$	(9,802	)		$	(9,802	)
	Gain arising from ineffective portion of commodity contracts	—				158				158
	Total impact on purchased gas cost	—				(9,644		)		(9,644		)
	Net loss on settled interest rate agreements reclassified from AOCI into interest expense	(2,432		)		—				(2,432		)
	Total Impact from Cash Flow Hedges	$	(2,432	)		$	(9,644	)		$	(12,076	)
Other comprehensive income from hedging table	'
	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, 2014 and 2013. 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
		June 30								June 30
		2014				2013				2014				2013
		(In thousands)
	Increase (decrease) in fair value:
	Interest rate agreements	$	(24,111	)		$	30,408			$	(38,559	)		$	65,308
	Forward commodity contracts	96				(3,168		)		11,805				(1,015		)
	Recognition of (gains) losses in earnings due to settlements:
	Interest rate agreements	671				671				2,014				1,544
	Forward commodity contracts	(2,567		)		(340		)		(5,357		)		5,980
	Total other comprehensive income (loss) from hedging, net of tax(1)	$	(25,911	)		$	27,571			$	(30,097	)		$	71,817
	(1)	Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.
Expected recognition in earnings of deferred gains/(losses) in AOCI table	'
	The following amounts, net of deferred taxes, represent the expected recognition in earnings of the deferred gains (losses) recorded in AOCI associated with our financial instruments, based upon the fair values of these financial instruments as of June 30, 2014. 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				Commodity				Total
		Agreements				Contracts
		(In thousands)
	Next twelve months	$	(1,317	)		$	2,407			$	1,090
	Thereafter	(27,033		)		(435		)		(27,468		)
	Total(1)	$	(28,350	)		$	1,972			$	(26,378	)
	(1)	Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Table)	9 Months Ended
	Jun. 30, 2014
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.
		Available-			Interest			Commodity			Total
		for-Sale			Rate			Contracts
		Securities			Agreement			Cash Flow
					Cash Flow			Hedges
					Hedges
		(In thousands)
	30-Sep-13	$	5,448		$	37,906		$	(4,476	)	$	38,878
	Other comprehensive income (loss) before reclassifications	3,212			(38,559		)	11,805			(23,542		)
	Amounts reclassified from accumulated other comprehensive income	(693		)	2,014			(5,357		)	(4,036		)
	Net current-period other comprehensive income (loss)	2,519			(36,545		)	6,448			(27,578		)
	30-Jun-14	$	7,967		$	1,361		$	1,972		$	11,300
		Available-			Interest			Commodity			Total
		for-Sale			Rate			Contracts
		Securities			Agreement			Cash Flow
					Cash Flow			Hedges
					Hedges
		(In thousands)
	30-Sep-12	$	5,661		$	(44,273	)	$	(8,995	)	$	(47,607	)
	Other comprehensive income (loss) before reclassifications	449			65,308			(1,015		)	64,742
	Amounts reclassified from accumulated other comprehensive income	(1,370		)	1,544			5,980			6,154
	Net current-period other comprehensive income (loss)	(921		)	66,852			4,965			70,896
	30-Jun-13	$	4,740		$	22,579		$	(4,030	)	$	23,289
Reclassification out of Accumulated Other Comprehensive Income	'
	The following tables detail reclassifications out of AOCI for the three and nine months ended June 30, 2014 and 2013. Amounts in parentheses below indicate decreases to net income in the statement of income.
		Three Months Ended June 30, 2014
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	733		Operation and maintenance expense
		733			Total before tax
		(267		)	Tax expense
		$	466		Net of tax
	Cash flow hedges
	Interest rate agreements	$	(1,057	)	Interest charges
	Commodity contracts	4,209			Purchased gas cost
		3,152			Total before tax
		(1,256		)	Tax expense
		$	1,896		Net of tax
	Total reclassifications	$	2,362		Net of tax
		Three Months Ended June 30, 2013
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	(531	)	Operation and maintenance expense
		(531		)	Total before tax
		193			Tax benefit
		$	(338	)	Net of tax
	Cash flow hedges
	Interest rate agreements	$	(1,057	)	Interest charges
	Commodity contracts	558			Purchased gas cost
		(499		)	Total before tax
		168			Tax benefit
		$	(331	)	Net of tax
	Total reclassifications	$	(669	)	Net of tax
		Nine Months Ended June 30, 2014
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in  the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	1,091		Operation and maintenance expense
		1,091			Total before tax
		(398		)	Tax expense
		$	693		Net of tax
	Cash flow hedges
	Interest rate agreements	$	(3,172	)	Interest charges
	Commodity contracts	8,783			Purchased gas cost
		5,611			Total before tax
		(2,268		)	Tax expense
		$	3,343		Net of tax
	Total reclassifications	$	4,036		Net of tax
		Nine Months Ended June 30, 2013
	Accumulated Other Comprehensive Income Components	Amount Reclassified from			Affected Line Item in  the
		Accumulated Other			Statement of Income
		Comprehensive Income
		(In thousands)
	Available-for-sale securities	$	2,158		Operation and maintenance expense
		2,158			Total before tax
		(788		)	Tax expense
		$	1,370		Net of tax
	Cash flow hedges
	Interest rate agreements	$	(2,432	)	Interest charges
	Commodity contracts	(9,803		)	Purchased gas cost
		(12,235		)	Total before tax
		4,711			Tax benefit
	$	(7,524	)	Net of tax
Total reclassifications	$	(6,154	)	Net of tax

Fair_Value_Measurements_Table

Fair Value Measurements (Table)	9 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair value measurements table	'
	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, 2014 and September 30, 2013. Assets and liabilities are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement.
		Quoted		Significant		Significant			Netting and			30-Jun-14
		Prices in		Other		Other			Cash
		Active		Observable		Unobservable			Collateral(2)
		Markets		Inputs		Inputs
		(Level 1)		(Level 2)(1)		(Level 3)
		(In thousands)
	Assets:
	Financial instruments
	Natural gas distribution segment	$	—	$	57,146	$	—		$	—		$	57,146
	Nonregulated segment	3		74,887		—			(61,863		)	13,027
	Total financial instruments	3		132,033		—			(61,863		)	70,173
	Hedged portion of gas stored underground	39,191		—		—			—			39,191
	Available-for-sale securities
	Money market funds	—		1,959		—			—			1,959
	Registered investment companies	45,554		—		—			—			45,554
	Bonds	—		33,397		—			—			33,397
	Total available-for-sale securities	45,554		35,356		—			—			80,910
	Total assets	$	84,748	$	167,389	$	—		$	(61,863	)	$	190,274
	Liabilities:
	Financial instruments
	Natural gas distribution segment	$	—	$	7,633	$	—		$	—		$	7,633
	Nonregulated segment	108		71,444		—			(71,552		)	—
	Total liabilities	$	108	$	79,077	$	—		$	(71,552	)	$	7,633
		Quoted		Significant		Significant			Netting and			30-Sep-13
		Prices in		Other		Other			Cash
		Active		Observable		Unobservable			Collateral(3)
		Markets		Inputs		Inputs
		(Level 1)		(Level 2)(1)		(Level 3)
		(In thousands)
	Assets:
	Financial instruments
	Natural gas distribution segment	$	—	$	111,191	$	—		$	—		$	111,191
	Nonregulated segment	745		115,135		—			(105,751		)	10,129
	Total financial instruments	745		226,326		—			(105,751		)	121,320
	Hedged portion of gas stored underground	44,758		—		—			—			44,758
	Available-for-sale securities
	Money market funds	—		4,428		—			—			4,428
	Registered investment companies	40,094		—		—			—			40,094
	Bonds	—		28,160		—			—			28,160
	Total available-for-sale securities	40,094		32,588		—			—			72,682
	Total assets	$	85,597	$	258,914	$	—		$	(105,751	)	$	238,760
	Liabilities:
	Financial instruments
	Natural gas distribution segment	$	—	$	1,543	$	—		$	—		$	1,543
	Nonregulated segment	158		130,422		—			(130,580		)	—
	Total liabilities	$	158	$	131,965	$	—		$	(130,580	)	$	1,543
	(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 which are valued at cost.
	(2)	This column reflects adjustments to our gross financial instrument assets and liabilities to reflect netting permitted under our master netting agreements and the relevant authoritative accounting literature. In addition, as of June 30, 2014, we had $9.7 million of cash held in margin accounts to collateralize certain financial instruments. Of this amount, $1.8 million was used to offset current risk management liabilities under master netting arrangements and the remaining $7.9 million is classified as current risk management assets.
	(3)	This column reflects adjustments to our gross financial instrument assets and liabilities to reflect netting permitted under our master netting agreements and the relevant authoritative accounting literature. In addition, as of September 30, 2013 we had $24.8 million of cash held in margin accounts to collateralize certain financial instruments. Of this amount, $14.7 million was used to offset current and noncurrent risk management liabilities under master netting arrangements and the remaining $10.1 million is classified as current risk management assets.
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]	'
	Available-for-sale securities are comprised of the following:
		Amortized		Gross		Gross			Fair
		Cost		Unrealized		Unrealized			Value
				Gain		Loss
		(In thousands)
	As of June 30, 2014
	Domestic equity mutual funds	$	27,983	$	10,274	$	—		$	38,257
	Foreign equity mutual funds	5,092		2,205		—			7,297
	Bonds	33,180		220		(3		)	33,397
	Money market funds	1,959		—		—			1,959
		$	68,214	$	12,699	$	(3	)	$	80,910
	As of September 30, 2013
	Domestic equity mutual funds	$	27,043	$	7,476	$	(23	)	$	34,496
	Foreign equity mutual funds	4,536		1,062		—			5,598
	Bonds	28,016		168		(24		)	28,160
	Money market funds	4,428		—		—			4,428
		$	64,023	$	8,706	$	(47	)	$	72,682
Other fair value measurements table	'
	The following table presents the carrying value and fair value of our debt as of June 30, 2014 and September 30, 2013:
		30-Jun-14		30-Sep-13
		(In thousands)
	Carrying Amount	$	2,460,000	$	2,460,000
	Fair Value	$	2,795,188	$	2,676,487

Discontinued_Operations_Table

Discontinued Operations (Table)	9 Months Ended
	Jun. 30, 2014
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued operations income statement detail table	'
	The table below sets forth statement of income data related to discontinued operations. At June 30, 2014 and September 30, 2013 we did not have any assets or liabilities held for sale.
		Three Months Ended				Nine Months Ended
		June 30				June 30
		2014		2013		2014		2013
		(In thousands)
	Operating revenues	$	—	$	—	$	—	$	37,962
	Purchased gas cost	—		—		—		21,464
	Gross profit	—		—		—		16,498
	Operating expenses	—		—		—		5,858
	Operating income	—		—		—		10,640
	Other nonoperating income	—		—		—		548
	Income from discontinued operations before income taxes	—		—		—		11,188
	Income tax expense	—		—		—		3,986
	Income from discontinued operations	—		—		—		7,202
	Gain on sale of discontinued operations, net of tax	—		5,294		—		5,294
	Net income from discontinued operations	$	—	$	5,294	$	—	$	12,496

Nature_of_Business_Details

Nature of Business (Details)	Jun. 30, 2014
	state
	regulated_gas_distributions_divisions
	customers
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Number of Customers, Natural Gas Distribution	3,000,000
Number of Divisions, Natural Gas Distribution	6
Number of States in which Entity Operates	8
Number of Customers, discontinued operations	64,000

Unaudited_Interim_Financial_In

Unaudited Interim Financial Information (Details) (USD $)	3 Months Ended
	Jun. 30, 2014		Sep. 30, 2013
Regulatory Asset [Line Items]	'		'
Regulatory assets	$250,300,000		$286,748,000
Regulatory Liabilities [Line Items]	'		'
Regulatory liabilities	521,592,000		453,581,000
Regulatory asset - future recoverable pension costs	18,000,000		17,400,000
Regulatory noncurrent asset, amortization period	'20		'
Deferred Gas Costs [Member]	'		'
Regulatory Liabilities [Line Items]	'		'
Regulatory liabilities	62,522,000		16,481,000
Deferred Franchise Fees [Member]	'		'
Regulatory Liabilities [Line Items]	'		'
Regulatory liabilities	5,918,000		1,689,000
Regulatory Cost of Removal Obligation [Member]	'		'
Regulatory Liabilities [Line Items]	'		'
Regulatory liabilities	441,643,000		427,524,000
Other [Member]	'		'
Regulatory Liabilities [Line Items]	'		'
Regulatory liabilities	11,509,000		7,887,000
Pension And Postretirement Benefit Costs [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	172,844,000	[1]	187,977,000	[1]
Merger And Integration Costs Net [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	4,860,000		5,250,000
Deferred Gas Costs Asset [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	9,809,000		15,152,000
Regulatory Cost of Removal Asset [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	9,552,000		10,008,000
Rate Case Costs [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	4,436,000		6,329,000
Texas 8.209 [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	19,349,000	[2]	30,364,000	[2]
APT Annual Adjustment Mechanism [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	5,927,000		5,853,000
Recoverable Loss On Reacquired Debt [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	19,517,000		21,435,000
Other [Member]	'		'
Regulatory Asset [Line Items]	'		'
Regulatory assets	$4,006,000		$4,380,000
[1]	Includes $18.0 million and $17.4 million of pension and postretirement expense deferred pursuant to regulatory authorization.
[2]	Texas Rule 8.209 is a Railroad Commission rule that allows for the deferral of all expenses associated with capital expenditures incurred pursuant to this rule, including the recording of interest on the deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recovered through base rates.

Segment_Information_Details

Segment Information (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Apr. 02, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013	Sep. 30, 2012
				segment
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'
Number of operating segments	'	'	'	3	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Total operating revenues	'	$942,718	$857,935	$4,162,188	$3,201,086	'	'
Purchased gas cost	'	583,185	541,438	2,917,421	2,089,476	'	'
Gross profit	'	359,533	316,497	1,244,767	1,111,610	'	'
Operating expenses	'	'	'	'	'	'	'
Operation and maintenance	'	125,559	121,258	365,991	338,871	'	'
Depreciation and amortization	'	63,955	58,129	185,731	174,888	'	'
Taxes, other than income	'	63,414	50,714	165,640	146,355	'	'
Total operating expenses	'	252,928	230,101	717,362	660,114	'	'
Operating income	'	106,605	86,396	527,405	451,496	'	'
Miscellaneous income (expense)	'	-374	-467	-4,022	1,943	'	'
Interest charges	'	31,840	32,741	95,556	96,594	'	'
Income (loss) before income taxes	'	74,391	53,188	427,827	356,845	'	'
Income tax expense (benefit)	'	28,670	19,714	161,723	133,683	'	'
Income (loss) from continuing operations	'	45,721	33,474	266,104	223,162	'	'
Income from discontinued operations, net of tax	'	0	0	0	7,202	'	'
Gain (loss) on sale of discontinued operations, net of tax	5,300	0	5,294	0	5,294	'	'
Net income (loss)	'	45,721	38,768	266,104	235,658	'	'
Capital expenditures	'	193,591	193,356	552,600	582,473	'	'
ASSETS	'	'	'	'	'	'	'
Net property, plant and equipment	'	6,461,450	'	6,461,450	'	6,030,655	'
Investment in subsidiaries	'	0	'	0	'	0	'
Current assets	'	'	'	'	'	'	'
Cash and cash equivalents	'	51,421	31,979	51,421	31,979	66,199	64,239
Assets from risk management activities	'	44,356	'	44,356	'	11,966	'
Other current assets	'	678,866	'	678,866	'	598,968	'
Intercompany receivables	'	0	'	0	'	0	'
Total current assets	'	774,643	'	774,643	'	677,133	'
Goodwill	'	741,363	'	741,363	'	741,363	'
Noncurrent assets from risk management activities	'	25,817	'	25,817	'	109,354	'
Deferred charges and other assets	'	353,916	'	353,916	'	375,763	'
Total Assets	'	8,357,189	'	8,357,189	'	7,934,268	'
CAPITALIZATION AND LIABILITIES	'	'	'	'	'	'	'
Shareholders' equity	'	3,116,685	'	3,116,685	'	2,580,409	'
Long-term debt	'	1,955,907	'	1,955,907	'	2,455,671	'
Total capitalization	'	5,072,592	'	5,072,592	'	5,036,080	'
Current liabilities	'	'	'	'	'	'	'
Current maturities of long-term debt	'	500,000	'	500,000	'	0	'
Short-term debt	'	0	'	0	'	367,984	'
Liabilities from risk management activities	'	609	'	609	'	1,543	'
Other current liabilities	'	655,088	'	655,088	'	608,959	'
Intercompany payables	'	0	'	0	'	0	'
Total current liabilities	'	1,155,697	'	1,155,697	'	978,486	'
Deferred income taxes	'	1,341,294	'	1,341,294	'	1,164,053	'
Derivative Liability, Noncurrent	'	7,024	'	7,024	'	'	'
Regulatory cost of removal obligation	'	391,785	'	391,785	'	359,299	'
Pension and postretirement liabilities	'	347,344	'	347,344	'	358,787	'
Deferred credits and other liabilities	'	41,453	'	41,453	'	37,563	'
Total Equity and Liabilities	'	8,357,189	'	8,357,189	'	7,934,268	'
Reportable Subsegments [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	942,718	857,935	4,162,188	3,201,086	'	'
Intersubsegment Eliminations [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	0	0	0	0	'	'
Natural Gas Distribution Segment [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Total operating revenues	'	517,707	467,144	2,652,532	2,039,107	'	'
Purchased gas cost	'	260,042	227,649	1,710,508	1,172,975	'	'
Gross profit	'	257,665	239,495	942,024	866,132	'	'
Operating expenses	'	'	'	'	'	'	'
Operation and maintenance	'	92,994	93,490	289,433	266,570	'	'
Depreciation and amortization	'	52,542	48,368	152,113	146,059	'	'
Taxes, other than income	'	57,596	45,686	155,286	132,029	'	'
Total operating expenses	'	203,132	187,544	596,832	544,658	'	'
Operating income	'	54,533	51,951	345,192	321,474	'	'
Miscellaneous income (expense)	'	678	268	304	2,728	'	'
Interest charges	'	23,649	25,001	69,802	74,228	'	'
Income (loss) before income taxes	'	31,562	27,218	275,694	249,974	'	'
Income tax expense (benefit)	'	13,033	11,401	105,665	94,874	'	'
Income (loss) from continuing operations	'	'	15,817	'	155,100	'	'
Income from discontinued operations, net of tax	'	'	'	'	7,202	'	'
Gain (loss) on sale of discontinued operations, net of tax	'	'	5,649	'	5,649	'	'
Net income (loss)	'	18,529	21,466	170,029	167,951	'	'
Capital expenditures	'	146,860	114,606	413,921	391,942	'	'
ASSETS	'	'	'	'	'	'	'
Net property, plant and equipment	'	5,036,007	'	5,036,007	'	4,719,873	'
Investment in subsidiaries	'	933,660	'	933,660	'	831,136	'
Current assets	'	'	'	'	'	'	'
Cash and cash equivalents	'	17,042	'	17,042	'	4,237	'
Assets from risk management activities	'	36,438	'	36,438	'	1,837	'
Other current assets	'	461,644	'	461,644	'	428,366	'
Intercompany receivables	'	775,175	'	775,175	'	783,738	'
Total current assets	'	1,290,299	'	1,290,299	'	1,218,178	'
Goodwill	'	574,190	'	574,190	'	574,190	'
Noncurrent assets from risk management activities	'	20,708	'	20,708	'	109,354	'
Deferred charges and other assets	'	325,035	'	325,035	'	347,687	'
Total Assets	'	8,179,899	'	8,179,899	'	7,800,418	'
CAPITALIZATION AND LIABILITIES	'	'	'	'	'	'	'
Shareholders' equity	'	3,116,685	'	3,116,685	'	2,580,409	'
Long-term debt	'	1,955,907	'	1,955,907	'	2,455,671	'
Total capitalization	'	5,072,592	'	5,072,592	'	5,036,080	'
Current liabilities	'	'	'	'	'	'	'
Current maturities of long-term debt	'	500,000	'	500,000	'	0	'
Short-term debt	'	357,000	'	357,000	'	645,984	'
Liabilities from risk management activities	'	609	'	609	'	1,543	'
Other current liabilities	'	477,726	'	477,726	'	491,681	'
Intercompany payables	'	0	'	0	'	0	'
Total current liabilities	'	1,335,335	'	1,335,335	'	1,139,208	'
Deferred income taxes	'	988,737	'	988,737	'	871,360	'
Derivative Liability, Noncurrent	'	7,024	'	7,024	'	'	'
Regulatory cost of removal obligation	'	391,785	'	391,785	'	359,299	'
Pension and postretirement liabilities	'	347,344	'	347,344	'	358,787	'
Deferred credits and other liabilities	'	37,082	'	37,082	'	35,684	'
Total Equity and Liabilities	'	8,179,899	'	8,179,899	'	7,800,418	'
Natural Gas Distribution Segment [Member] | Reportable Subsegments [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	516,644	465,982	2,648,505	2,035,712	'	'
Natural Gas Distribution Segment [Member] | Intersubsegment Eliminations [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	1,063	1,162	4,027	3,395	'	'
Regulated Transmission and Storage Segment [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Total operating revenues	'	87,189	74,041	232,145	196,570	'	'
Purchased gas cost	'	0	0	0	0	'	'
Gross profit	'	87,189	74,041	232,145	196,570	'	'
Operating expenses	'	'	'	'	'	'	'
Operation and maintenance	'	23,570	17,035	57,465	48,745	'	'
Depreciation and amortization	'	10,281	8,676	30,223	25,756	'	'
Taxes, other than income	'	5,054	4,287	8,485	12,513	'	'
Total operating expenses	'	38,905	29,998	96,173	87,014	'	'
Operating income	'	48,284	44,043	135,972	109,556	'	'
Miscellaneous income (expense)	'	-489	-247	-2,751	-473	'	'
Interest charges	'	9,162	8,049	27,274	22,777	'	'
Income (loss) before income taxes	'	38,633	35,747	105,947	86,306	'	'
Income tax expense (benefit)	'	13,695	12,650	37,454	30,574	'	'
Income (loss) from continuing operations	'	'	23,097	'	55,732	'	'
Income from discontinued operations, net of tax	'	'	'	'	0	'	'
Gain (loss) on sale of discontinued operations, net of tax	'	'	0	'	0	'	'
Net income (loss)	'	24,938	23,097	68,493	55,732	'	'
Capital expenditures	'	45,658	78,012	137,579	189,051	'	'
ASSETS	'	'	'	'	'	'	'
Net property, plant and equipment	'	1,366,928	'	1,366,928	'	1,249,767	'
Investment in subsidiaries	'	0	'	0	'	0	'
Current assets	'	'	'	'	'	'	'
Cash and cash equivalents	'	0	'	0	'	0	'
Assets from risk management activities	'	0	'	0	'	0	'
Other current assets	'	15,813	'	15,813	'	11,709	'
Intercompany receivables	'	0	'	0	'	0	'
Total current assets	'	15,813	'	15,813	'	11,709	'
Goodwill	'	132,462	'	132,462	'	132,462	'
Noncurrent assets from risk management activities	'	0	'	0	'	0	'
Deferred charges and other assets	'	22,474	'	22,474	'	19,227	'
Total Assets	'	1,537,677	'	1,537,677	'	1,413,165	'
CAPITALIZATION AND LIABILITIES	'	'	'	'	'	'	'
Shareholders' equity	'	464,914	'	464,914	'	396,421	'
Long-term debt	'	0	'	0	'	0	'
Total capitalization	'	464,914	'	464,914	'	396,421	'
Current liabilities	'	'	'	'	'	'	'
Current maturities of long-term debt	'	0	'	0	'	0	'
Short-term debt	'	0	'	0	'	0	'
Liabilities from risk management activities	'	0	'	0	'	0	'
Other current liabilities	'	14,837	'	14,837	'	20,288	'
Intercompany payables	'	717,134	'	717,134	'	712,768	'
Total current liabilities	'	731,971	'	731,971	'	733,056	'
Deferred income taxes	'	338,350	'	338,350	'	283,554	'
Derivative Liability, Noncurrent	'	0	'	0	'	'	'
Regulatory cost of removal obligation	'	0	'	0	'	0	'
Pension and postretirement liabilities	'	0	'	0	'	0	'
Deferred credits and other liabilities	'	2,442	'	2,442	'	134	'
Total Equity and Liabilities	'	1,537,677	'	1,537,677	'	1,413,165	'
Regulated Transmission and Storage Segment [Member] | Reportable Subsegments [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	24,990	26,730	67,162	65,084	'	'
Regulated Transmission and Storage Segment [Member] | Intersubsegment Eliminations [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	62,199	47,311	164,983	131,486	'	'
Nonregulated Segment [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Total operating revenues	'	465,033	421,808	1,670,437	1,250,650	'	'
Purchased gas cost	'	450,220	418,548	1,599,469	1,200,624	'	'
Gross profit	'	14,813	3,260	70,968	50,026	'	'
Operating expenses	'	'	'	'	'	'	'
Operation and maintenance	'	9,129	11,034	19,463	24,679	'	'
Depreciation and amortization	'	1,132	1,085	3,395	3,073	'	'
Taxes, other than income	'	764	741	1,869	1,813	'	'
Total operating expenses	'	11,025	12,860	24,727	29,565	'	'
Operating income	'	3,788	-9,600	46,241	20,461	'	'
Miscellaneous income (expense)	'	1,018	215	1,785	1,791	'	'
Interest charges	'	610	392	1,840	1,687	'	'
Income (loss) before income taxes	'	4,196	-9,777	46,186	20,565	'	'
Income tax expense (benefit)	'	1,942	-4,337	18,604	8,235	'	'
Income (loss) from continuing operations	'	'	-5,440	'	12,330	'	'
Income from discontinued operations, net of tax	'	'	'	'	0	'	'
Gain (loss) on sale of discontinued operations, net of tax	'	'	-355	'	-355	'	'
Net income (loss)	'	2,254	-5,795	27,582	11,975	'	'
Capital expenditures	'	1,073	738	1,100	1,480	'	'
ASSETS	'	'	'	'	'	'	'
Net property, plant and equipment	'	58,515	'	58,515	'	61,015	'
Investment in subsidiaries	'	-2,096	'	-2,096	'	-2,096	'
Current assets	'	'	'	'	'	'	'
Cash and cash equivalents	'	34,379	'	34,379	'	61,962	'
Assets from risk management activities	'	7,918	'	7,918	'	10,129	'
Other current assets	'	581,221	'	581,221	'	452,126	'
Intercompany receivables	'	0	'	0	'	0	'
Total current assets	'	623,518	'	623,518	'	524,217	'
Goodwill	'	34,711	'	34,711	'	34,711	'
Noncurrent assets from risk management activities	'	5,109	'	5,109	'	0	'
Deferred charges and other assets	'	6,407	'	6,407	'	8,849	'
Total Assets	'	726,164	'	726,164	'	626,696	'
CAPITALIZATION AND LIABILITIES	'	'	'	'	'	'	'
Shareholders' equity	'	468,746	'	468,746	'	434,715	'
Long-term debt	'	0	'	0	'	0	'
Total capitalization	'	468,746	'	468,746	'	434,715	'
Current liabilities	'	'	'	'	'	'	'
Current maturities of long-term debt	'	0	'	0	'	0	'
Short-term debt	'	0	'	0	'	0	'
Liabilities from risk management activities	'	0	'	0	'	0	'
Other current liabilities	'	183,241	'	183,241	'	110,306	'
Intercompany payables	'	58,041	'	58,041	'	70,970	'
Total current liabilities	'	241,282	'	241,282	'	181,276	'
Deferred income taxes	'	14,207	'	14,207	'	8,960	'
Derivative Liability, Noncurrent	'	0	'	0	'	'	'
Regulatory cost of removal obligation	'	0	'	0	'	0	'
Pension and postretirement liabilities	'	0	'	0	'	0	'
Deferred credits and other liabilities	'	1,929	'	1,929	'	1,745	'
Total Equity and Liabilities	'	726,164	'	726,164	'	626,696	'
Nonregulated Segment [Member] | Reportable Subsegments [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	401,084	365,223	1,446,521	1,100,290	'	'
Nonregulated Segment [Member] | Intersubsegment Eliminations [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	63,949	56,585	223,916	150,360	'	'
Intersegment Elimination [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Total operating revenues	'	-127,211	-105,058	-392,926	-285,241	'	'
Purchased gas cost	'	-127,077	-104,759	-392,556	-284,123	'	'
Gross profit	'	-134	-299	-370	-1,118	'	'
Operating expenses	'	'	'	'	'	'	'
Operation and maintenance	'	-134	-301	-370	-1,123	'	'
Depreciation and amortization	'	0	0	0	0	'	'
Taxes, other than income	'	0	0	0	0	'	'
Total operating expenses	'	-134	-301	-370	-1,123	'	'
Operating income	'	0	2	0	5	'	'
Miscellaneous income (expense)	'	-1,581	-703	-3,360	-2,103	'	'
Interest charges	'	-1,581	-701	-3,360	-2,098	'	'
Income (loss) before income taxes	'	0	0	0	0	'	'
Income tax expense (benefit)	'	0	0	0	0	'	'
Income (loss) from continuing operations	'	'	0	'	0	'	'
Income from discontinued operations, net of tax	'	'	'	'	0	'	'
Gain (loss) on sale of discontinued operations, net of tax	'	'	0	'	0	'	'
Net income (loss)	'	0	0	0	0	'	'
Capital expenditures	'	0	0	0	0	'	'
ASSETS	'	'	'	'	'	'	'
Net property, plant and equipment	'	0	'	0	'	0	'
Investment in subsidiaries	'	-931,564	'	-931,564	'	-829,040	'
Current assets	'	'	'	'	'	'	'
Cash and cash equivalents	'	0	'	0	'	0	'
Assets from risk management activities	'	0	'	0	'	0	'
Other current assets	'	-379,812	'	-379,812	'	-293,233	'
Intercompany receivables	'	-775,175	'	-775,175	'	-783,738	'
Total current assets	'	-1,154,987	'	-1,154,987	'	-1,076,971	'
Goodwill	'	0	'	0	'	0	'
Noncurrent assets from risk management activities	'	0	'	0	'	0	'
Deferred charges and other assets	'	0	'	0	'	0	'
Total Assets	'	-2,086,551	'	-2,086,551	'	-1,906,011	'
CAPITALIZATION AND LIABILITIES	'	'	'	'	'	'	'
Shareholders' equity	'	-933,660	'	-933,660	'	-831,136	'
Long-term debt	'	0	'	0	'	0	'
Total capitalization	'	-933,660	'	-933,660	'	-831,136	'
Current liabilities	'	'	'	'	'	'	'
Current maturities of long-term debt	'	0	'	0	'	0	'
Short-term debt	'	-357,000	'	-357,000	'	-278,000	'
Liabilities from risk management activities	'	0	'	0	'	0	'
Other current liabilities	'	-20,716	'	-20,716	'	-13,316	'
Intercompany payables	'	-775,175	'	-775,175	'	-783,738	'
Total current liabilities	'	-1,152,891	'	-1,152,891	'	-1,075,054	'
Deferred income taxes	'	0	'	0	'	179	'
Derivative Liability, Noncurrent	'	0	'	0	'	'	'
Regulatory cost of removal obligation	'	0	'	0	'	0	'
Pension and postretirement liabilities	'	0	'	0	'	0	'
Deferred credits and other liabilities	'	0	'	0	'	0	'
Total Equity and Liabilities	'	-2,086,551	'	-2,086,551	'	-1,906,011	'
Intersegment Elimination [Member] | Reportable Subsegments [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	0	0	0	0	'	'
Intersegment Elimination [Member] | Intersubsegment Eliminations [Member]	'	'	'	'	'	'	'
Segment Reporting Information Profit Loss [Abstract]	'	'	'	'	'	'	'
Revenues from external customers	'	($127,211)	($105,058)	($392,926)	($285,241)	'	'

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Feb. 18, 2014	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'	'
Stock Issued During Period, Shares, New Issues	9,200,000	'	'	'	'
Shares Issued At Overallotment Option	1,200,000	'	'	'	'
Share Price	$44	'	'	'	'
Net proceeds from equity offering	$390,200,000	'	'	$390,205,000	$0
Basic Earnings per Share from Continuing Operations	'	'	'	'	'
Income from continuing operations	'	45,721,000	33,474,000	266,104,000	223,162,000
Less: Income from continuing operations allocated to participating securities	'	107,000	91,000	674,000	760,000
Income from continuing operations available to common shareholders	'	45,614,000	33,383,000	265,430,000	222,402,000
Basic weighted average shares outstanding	'	100,267,000	90,603,000	95,455,000	90,497,000
Income from continuing operations per share - Basic	'	$0.45	$0.37	$2.78	$2.46
Basic Earnings per Share from Discontinued Operations	'	'	'	'	'
Income from discontinued operations, net of tax	'	0	5,294,000	0	12,496,000
Less: Income from discontinued operations allocated to participating securities	'	0	14,000	0	43,000
Income from discontinued operations available to common shareholders	'	0	5,280,000	0	12,453,000
Basic weighted average shares outstanding	'	100,267,000	90,603,000	95,455,000	90,497,000
Income from discontinued operations per share - Basic	'	$0	$0.06	$0	$0.14
Net income per share - Basic	'	$0.45	$0.43	$2.78	$2.60
Diluted Earnings per Share from Continuing Operations	'	'	'	'	'
Income from continuing operations available to common shareholders	'	45,614,000	33,383,000	265,430,000	222,402,000
Effect of dilutive stock options and other shares	'	0	0	4,000	5,000
Income from continuing operations available to common shareholders	'	45,614,000	33,383,000	265,434,000	222,407,000
Basic weighted average shares outstanding	'	100,267,000	90,603,000	95,455,000	90,497,000
Additional dilutive stock options and other shares	'	883,000	947,000	884,000	948,000
Diluted weighted average shares outstanding	'	101,150,000	91,550,000	96,339,000	91,445,000
Income from continuing operations per share - Diluted	'	$0.45	$0.36	$2.76	$2.43
Diluted Earnings per Share from Discontinued Operations	'	'	'	'	'
Income from discontinued operations available to common shareholders	'	0	5,280,000	0	12,453,000
Effect of dilutive stock options and other shares	'	0	0	0	0
Net Income Loss From Discontinued Operations Available To Common Stockholders Diluted	'	0	5,280,000	0	12,453,000
Basic weighted average shares outstanding	'	100,267,000	90,603,000	95,455,000	90,497,000
Additional dilutive stock options and other shares	'	883,000	947,000	884,000	948,000
Diluted weighted average shares outstanding	'	101,150,000	91,550,000	96,339,000	91,445,000
Income from discontinued operations per share - Diluted	'	$0	$0.06	$0	$0.14
Net income per share - Diluted	'	$0.45	$0.42	$2.76	$2.57
Earnings Per Share Diluted Other Disclosures Abstract	'	'	'	'	'
Anti-dilutive stock options excluded from computation of diluted earnings per share (in shares)	'	0	0	0	0
Share Repurchase Program - Shares Purchased	'	'	'	0	0
Share Repurchase Program - Amount Purchased	'	'	'	0	0
Authorized Commercial Paper	$950,000,000	$950,000,000	'	$950,000,000	'

Debt_Details

Debt (Details) (USD $)

0 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

Feb. 18, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2013

Sep. 30, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2013

Minimum [Member]

Maximum [Member]

First Facility Regulated Operations [Member]

Second Facility Regulated Operations [Member]

Third Facility Regulated Operations [Member]

Intercompany Facility Regulated Operations [Member]

Committed Facility Nonregulated Operations [Member]

Committed Facility Nonregulated Operations [Member]

Uncommitted Facility Nonregulated Operations [Member]

Intercompany Facility Nonregulated Operations [Member]

Nonregulated Facilities [Member]

Regulated Facilities [Member]

Unsecured Senior Notes Due 2014 [Member]

Unsecured Senior Notes Due 2014 [Member]

Unsecured Senior Notes Due 2017 [Member]

Unsecured Senior Notes Due 2017 [Member]

Unsecured Senior Notes Due 2019 [Member]

Unsecured Senior Notes Due 2019 [Member]

Unsecured Senior Notes Due 2034 [Member]

Unsecured Senior Notes Due 2034 [Member]

Unsecured Senior Notes Due 2041 [Member]

Unsecured Senior Notes Due 2041 [Member]

Unsecured Senior Notes Due 2043 [Member]

Unsecured Senior Notes Due 2043 [Member]

Medium Term Notes Due 2025 [Member]

Medium Term Notes Due 2025 [Member]

Unsecured Debentures Due 2028 [Member]

Unsecured Debentures Due 2028 [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument Carrying Amount

'

$2,460,000,000

$2,460,000,000

'

$2,460,000,000

'

'

'

'

'

'

'

'

'

'

'

'

$500,000,000

$500,000,000

$250,000,000

$250,000,000

$450,000,000

$450,000,000

$200,000,000

$200,000,000

$400,000,000

$400,000,000

$500,000,000

$500,000,000

$10,000,000

$10,000,000

$150,000,000

$150,000,000

Debt Instrument, Interest Rate, Stated Percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

4.95%

4.95%

6.35%

6.35%

8.50%

8.50%

5.95%

5.95%

5.50%

5.50%

4.15%

4.15%

6.67%

6.67%

6.75%

6.75%

Debt Instrument, Maturity Date

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

15-Oct-14

15-Oct-14

15-Jun-17

15-Jun-17

15-Mar-19

15-Mar-19

15-Oct-34

15-Oct-34

15-Jun-41

15-Jun-41

15-Jan-43

15-Jan-43

15-Dec-25

15-Dec-25

15-Jul-28

15-Jul-28

Debt Instrument, Unamortized Discount

'

4,093,000

4,093,000

'

4,329,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Current maturities of long-term debt

'

500,000,000

500,000,000

'

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt

'

1,955,907,000

1,955,907,000

'

2,455,671,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line Of Credit Facility [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line Of Credit Facility Maximum Borrowing Capacity

'

1,000,000,000

1,000,000,000

'

'

'

'

950,000,000

25,000,000

10,000,000

500,000,000

15,000,000

25,000,000

25,000,000

500,000,000

'

985,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Current Available Borrowing Capacity

'

'

'

'

'

'

'

'

'

4,100,000

'

'

'

'

'

52,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Maximum Borrowing Capacity with Accordion Feature

'

'

'

'

'

'

'

1,200,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Amended Maximum Borrowing Capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

50,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line Of Credit Facility Description

'

'

'

'

'

'

'

'

'

'

'which bears interest at the lower of (i)B the Eurodollar rate under the five-year revolving credit facility or (ii)B the rate outstanding under the commercial paper program

'

'

'

'This facility bears interest at a rate equal to the one-month LIBOR rate plus 3.00 percent or (ii) the rate for AEM's borrowings under its committed credit facility plus 0.75 percent.

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Covenant, Excess Debt Trigger

'

'

'

'

'

15,000,000

100,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long Term Debt Other Disclosures [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Authorized Commercial Paper

950,000,000

950,000,000

950,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Commercial Paper

'

0

0

'

368,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt and Equity Securities Authorized for Issuance

'

1,750,000,000

1,750,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt And Equity Securities Available For Issuance

'

1,350,000,000

1,350,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

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'

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'

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'

'

'

'

'

Regulated Operations Line of Credit Facilities, Covenant Terms

'

'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.

'

'

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'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Ratio of Total Debt to Total Capital

'

46.00%

46.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

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'

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'

'

'

'

'

'

'

Debt Instrument Covenant Description

'

'In addition to these financial covenants, our credit facilities and 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 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.

'

'

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'

'

'

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'

'

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Debt Instrument Covenant Compliance

'

'We were in compliance with all of our debt covenants as of June 30, 2014.

'

'

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'

'

'

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'

'

'

'

'

'

'

'

'

Stock Issued During Period, Shares, New Issues

9,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net proceeds from equity offering

$390,200,000

'

$390,205,000

$0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

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'

Interim_Pension_and_Other_Post2

Interim Pension and Other Postretirement Benefits (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Oct. 02, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Pension Benefits [Member]	'	'	'	'	'
Components of net periodic pension cost [Abstract]	'	'	'	'	'
Service Cost	'	$4,738,000	$5,194,000	$14,214,000	$15,599,000
Interest Cost	'	6,824,000	6,019,000	20,472,000	18,067,000
Expected return on assets	'	-5,901,000	-5,739,000	-17,702,000	-17,216,000
Amortization of transition (asset)/obligation	'	0	0	0	0
Amortization of prior service (credit)/cost	'	-34,000	-35,000	-102,000	-106,000
Amortization of actuarial (gain) loss	'	3,931,000	5,432,000	11,793,000	16,555,000
Settlement loss	4,500,000	0	3,161,000	4,539,000	3,161,000
Net periodic pension cost	'	9,558,000	14,032,000	33,214,000	36,060,000
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract	'	'	'	'	'
Discount Rate	'	4.95%	4.04%	4.95%	4.04%
Rate of compensation increase	'	3.50%	3.50%	3.50%	3.50%
Expected return on plan assets	'	7.25%	7.75%	7.25%	7.75%
Current Year Benefit Plan Contributions [Abstract]	'	'	'	'	'
Contributions Actual	'	'	'	27,100,000	'
Benefit Payment	16,800,000	'	'	'	'
Supplemental Employee Retirement Plan, Defined Benefit [Member]	'	'	'	'	'
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract	'	'	'	'	'
Discount Rate	'	4.95%	4.21%	4.95%	4.21%
Rate of compensation increase	'	3.50%	3.50%	3.50%	3.50%
Current Year Benefit Plan Contributions [Abstract]	'	'	'	'	'
Effect on Net Periodic Cost Due To Discount Rate Change, Remaining Fiscal Year	'	'	100,000	'	100,000
Other Benefits [Member]	'	'	'	'	'
Components of net periodic pension cost [Abstract]	'	'	'	'	'
Service Cost	'	4,196,000	4,700,000	12,588,000	14,100,000
Interest Cost	'	3,987,000	3,241,000	11,963,000	9,723,000
Expected return on assets	'	-1,291,000	-997,000	-3,875,000	-2,991,000
Amortization of transition (asset)/obligation	'	69,000	271,000	205,000	811,000
Amortization of prior service (credit)/cost	'	-363,000	-363,000	-1,088,000	-1,088,000
Amortization of actuarial (gain) loss	'	158,000	1,049,000	474,000	3,147,000
Settlement loss	'	0	0	0	0
Net periodic pension cost	'	6,756,000	7,901,000	20,267,000	23,702,000
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract	'	'	'	'	'
Discount Rate	'	4.95%	4.04%	4.95%	4.04%
Expected return on plan assets	'	4.60%	4.70%	4.60%	4.70%
Current Year Benefit Plan Contributions [Abstract]	'	'	'	'	'
Contributions Actual	'	'	'	18,100,000	'
Other Benefits [Member] | Minimum [Member]	'	'	'	'	'
Current Year Benefit Plan Contributions [Abstract]	'	'	'	'	'
Defined Benefit Plan, Expected Contributions in Current Fiscal Year	'	'	'	20,000,000	'
Other Benefits [Member] | Maximum [Member]	'	'	'	'	'
Current Year Benefit Plan Contributions [Abstract]	'	'	'	'	'
Defined Benefit Plan, Expected Contributions in Current Fiscal Year	'	'	'	$25,000,000	'

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	0 Months Ended		3 Months Ended		9 Months Ended
	2-May-14	Jan. 25, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Loss Contingency Information About Litigation Matters Abstract	'	'	'	'	'	'
Description of Pending Litigation	'	'	'	'	' April 2009, Atmos Energy and two subsidiaries of AEH, AEM and Atmos Gathering Company, LLC (AGC) (collectively, the Atmos Entities), were involved in a lawsuit filed in the Circuit Court of Edmonson County, Kentucky related to our Park City Gathering Project. The dispute which gave rise to the litigation involves the amount of royalties due from a third party producer to landowners (who own the mineral rights) for natural gas produced from the landownersb properties. The third party producer was operating pursuant to leases between the landowners and certain investors/working interest owners. The third party producer filed a petition in bankruptcy, which was subsequently dismissed due to the lack of meaningful assets to reorganize or liquidate.Although certain Atmos Energy companies entered into contracts with the third party producer to gather, treat and ultimately sell natural gas produced from the landownersb properties, no Atmos Energy company had a contractual relationship with the landowners or the investors/working interest owners. After the lawsuit was filed, the landowners were successful in terminating for non-payment of royalties the leases related to the production of natural gas from their properties. Subsequent to termination, the investors/working interest owners under such leases filed additional claims against us for the termination of the leases.During the trial, the landowners and the investors/working interest owners requested an award of compensatory damages plus punitive damages against us. On DecemberB 17, 2010, the jury returned a verdict in favor of the landowners and investor/working interest owners and awarded compensatory damages of $3.8 million and punitive damages of $27.5 million payable by Atmos Energy and the two AEH subsidiaries.A hearing was held on FebruaryB 28, 2011 to hear a number of motions, including a motion to dismiss the jury verdict and a motion for a new trial. The motions to dismiss the jury verdict and for a new trial were denied. However, the total punitive damages award was reduced from $27.5 million to $24.7 million. On OctoberB 17, 2011, we filed our brief of appellants with the Kentucky Court of Appeals, appealing the verdict of the trial court. The appellees in this case subsequently filed their appelleesb brief with the Court of Appeals on JanuaryB 16, 2012, with our reply brief being filed with the Court of Appeals on MarchB 19, 2012. Oral arguments were held in the case on AugustB 27, 2012.In an opinion handed down on JanuaryB 25, 2013, the Court of Appeals overturned the $28.5 million jury verdict returned against the Atmos Entities. In a unanimous decision by a three-judge panel, the Court of Appeals reversed the claims asserted by the landowners and investors/working interest owners. The Court of Appeals concluded that all of such claims that the Atmos Entities appealed should have been dismissed by the trial court as a matter of law. The Court of Appeals let stand the jury verdict on one claim that Atmos Energy and our subsidiaries chose not to appeal, which was a trespass claim. The jury had awarded a total of $10,000 in compensatory damages plus accrued interest to one landowner on that claim. The claim was paid on February 18, 2013. The Court of Appeals vacated all of the other damages awarded by the jury and remanded the case to the trial court for a new trial, solely on the issue of whether punitive damages should be awarded to that landowner and, if so, in what amount. The investors/working interest owners, on FebruaryB 25, 2013, and the landowners, on MarchB 19, 2013, then each filed with the Supreme Court of Kentucky, separate motions for discretionary review of the opinion of the Court of Appeals. We filed responses to the motions. The Kentucky Supreme Court denied the motions for discretionary review on February 12, 2014 and the decision of the Court of Appeals became final on February 21, 2014.B We had previously accrued what we believed to be an adequate amount for the anticipated resolution of this matter. This accrual was reversed during the second fiscal quarter of fiscal 2014 as the appellate process in this case had been completed. Atmos Energy had also filed a motion with the trial court, the Circuit Court of Edmonson County, Kentucky, on March 10, 2014, seeking a ruling that the remaining landowner was not entitled to any punitive damages on the sole remaining claim of trespass. B On May 19, 2014, the Edmonson County Circuit Court entered judgment dismissing any claim for punitive damages relating to the trespass claim. There was no appeal of this judgment. The lawsuit in Edmonson County has now been fully and finally resolved.In addition, in a related matter, on JulyB 12, 2011, the Atmos Entities filed a lawsuit in the United States District Court, Western District of Kentucky, Atmos Energy Corporation et al.vs. Resource Energy Technologies, LLC and Robert Thorpe and John F. Charles, against the third party producer and its affiliates to recover all costs, including attorneysb fees, incurred by the Atmos Entities, which are associated with the defense and appeal of the case discussed above as well as for all damages awarded to the plaintiffs in such case against the Atmos Entities. The total amount of damages being claimed in the lawsuit is bopen-endedb since the appellate process and related costs are ongoing. This lawsuit is based upon the indemnification provisions agreed to by the third party producer in favor of Atmos Gathering that are contained in an agreement entered into between AGC and the third party producer in May 2009. The defendants filed a motion to dismiss the case on AugustB 25, 2011, with Atmos Energy filing a brief in response to such motion on SeptemberB 19, 2011. On MarchB 27, 2012 the court denied the motion to dismiss. Atmos Energy filed a motion for partial summary judgment against the defendants with the District Court on July 15, 2014, with a ruling by the Court still pending. This case is scheduled for trial beginning October 6, 2014.	'
Loss Contingency, Compensatory Damages Awarded, Value	'	$10,000	'	'	'	'
Business License Tax [Abstract]	'	'	'	'	'	'
Business License Tax Examination, Description	'	'	'	'	'Atmos Energy, through its affiliate, AEM, has been involved in a dispute with the Tennessee Department of Revenue (TDOR) regarding sales business tax audits over a period of several years. The cumulative assessment approximated $12 million as of March 31, 2014, which AEM challenged. We had previously accrued in prior years what we believed to be an adequate amount for the anticipated resolution of this matter. With respect to certain issues, AEM and the TDOR filed competing Partial Motions for Summary Judgment with the Chancery Court. On August 2, 2013, the Chancery Court granted the TDOR's Partial Motion for Summary Judgment and denied AEM's Partial Motion for Summary Judgment. An agreed order of dismissal with prejudice betweenB B B B AEM and TDOR was approved by the Chancery Court and entered on May 2, 2014, whereby AEM agreed to pay $6.2 million to TDOR to resolve all business tax-related liabilities outstanding through September 2014. The State of Tennessee also passed related legislation, effective July 1, 2014, that should help minimize any disputes over this type of sales business tax in the future.	'
Business License Tax Examination, Settlement Amount	6,200,000	'	'	'	'	'
Long Term Purchase Commitment [Line Items]	'	'	'	'	'	'
Significant Purchase Commitment Amount	'	'	$383,200,000	$340,900,000	$1,354,500,000	$958,200,000
Inventories Under Indexed Contracts [Member]	'	'	'	'	'	'
Long Term Purchase Commitment [Line Items]	'	'	'	'	'	'
Long Term Purchase Commitment Minimum Quantity Required Within One Year	'	'	105,200	'	105,200	'
Long Term Purchase Commitment Minimum Quantity Required One To Three Years	'	'	18,000	'	18,000	'
Long Term Purchase Commitment Minimum Quantity Required After Three Years	'	'	600	'	600	'
Inventories Under Fixed Price Contracts [Member]	'	'	'	'	'	'
Long Term Purchase Commitment [Line Items]	'	'	'	'	'	'
Long Term Purchase Commitment Minimum Quantity Required Within One Year	'	'	10,000	'	10,000	'
Purchase Commitment Amount Minimum	'	'	3.66	'	3.66	'
Purchase Commitment Amount Maximum	'	'	6.36	'	6.36	'

Commitments_and_Contingencies_2

Commitments and Contingencies Commitments and Contingencies Future Estimated Purchase Commitment (Details) (Public Utilities, Inventory, Fuel [Member], Mid-Tex Division [Member], USD $)	Jun. 30, 2014
In Thousands, unless otherwise specified
Public Utilities, Inventory, Fuel [Member] | Mid-Tex Division [Member]	'
Unrecorded Unconditional Purchase Obligation [Line Items]	'
Unrecorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year	$51,946
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months	234,824
Unrecorded Unconditional Purchase Obligation, Due within Two Years	167,747
Unrecorded Unconditional Purchase Obligation, Due within Three Years	67,185
Unrecorded Unconditional Purchase Obligation, Due within Four Years	0
Unrecorded Unconditional Purchase Obligation	$521,702

Financial_Instruments_Descript

Financial Instruments Descriptions (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
			MMcf
General Discussion Of Derivative Instruments And Hedging Activities [Abstract]	'	'	'	'
Minimum Hedge Percentage Of Anticipated Heating Season Gas	'	'	25.00%	'
Maximum Hedge Percentage Of Anticipated Heating Season Gas	'	'	50.00%	'
Hedge Percentage Of Actual Heating Season Gas	'	'	32.00%	'
Hedge Volume Of Actual Heating Season Gas	'	'	24,600	'
Minimum Length Of Time Hedged In Cash Flow Hedge	'1 month	'	'	'
Maximum Length Of Time Hedged In Cash Flow Hedge	'46 months	'	'	'
Gain (Loss) On Hedge Ineffectiveness	($0.10)	($0.40)	$1.30	$17.30
Regulated Segments Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate	'	'	37.00%	'
Nonregulated Segment Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate	'	'	39.00%	'
Gain (Loss) On Derivative Instruments Not Designated Hedges Net Pretax	-0.6	-8.4	-10.7	-1.7
Interest Rate Hedges, Senior Notes 2015 Issuance [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Notional Amount of Interest Rate Cash Flow Hedge Derivatives	500	'	500	'
Anticipated Debt Issuance, Amount	500	'	500	'
Derivative, Average Forward Interest Rate	3.13%	'	3.13%	'
Interest Rate Hedges, Senior Notes 2017 Issuance [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Notional Amount of Interest Rate Cash Flow Hedge Derivatives	250	'	250	'
Anticipated Debt Issuance, Amount	250	'	250	'
Derivative, Average Forward Interest Rate	3.37%	'	3.37%	'
Interest Rate Hedges, Senior Notes 2019 Issuance [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Notional Amount of Interest Rate Cash Flow Hedge Derivatives	325	'	325	'
Anticipated Debt Issuance, Amount	$450	'	$450	'
Derivative, Average Forward Interest Rate	3.91%	'	3.91%	'

Financial_Instruments_Commodit

Financial Instruments Commodity Contract Volume (Details)	Jun. 30, 2014
	MMcf
Natural Gas Distribution Segment [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	20,826
Natural Gas Distribution Segment [Member] | Nondesignated [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	20,826
Natural Gas Distribution Segment [Member] | Fair Value Hedging [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	0
Natural Gas Distribution Segment [Member] | Cash Flow Hedging [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	0
Nonregulated Segment [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	83,843
Nonregulated Segment [Member] | Nondesignated [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	63,168
Nonregulated Segment [Member] | Fair Value Hedging [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	-9,255
Nonregulated Segment [Member] | Cash Flow Hedging [Member]	'
Commodity Contract Outstanding Volumes [Line Items]	'
Investment Contract Volume	29,930

Financial_Instruments_Balance_

Financial Instruments Balance Sheet Location (Details) (USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Derivatives Fair Value [Line Items]	'	'
Derivative, Collateral, Right to Reclaim Cash	$7,900	$10,100
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	1,800	14,700
Natural Gas Distribution Segment [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	57,146	111,191
Derivative Asset, Contract Netting	0	0
Derivative Asset, Net of Contract Netting	57,146	111,191
Derivative, Collateral, Right to Reclaim Cash	0	0
Derivative Asset	57,146	111,191
Derivative Liability, Fair Value, Gross Liability	-7,633	-1,543
Derivative Liability, Contract Netting	0	0
Derivative Liability, Net of Contract Netting	-7,633	-1,543
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	-7,633	-1,543
Nonregulated Segment [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	74,890	115,880
Derivative Asset, Contract Netting	-69,782	-115,875
Derivative Asset, Net of Contract Netting	5,108	5
Derivative, Collateral, Right to Reclaim Cash	7,919	10,124
Derivative Asset	13,027	10,129
Derivative Liability, Fair Value, Gross Liability	-71,552	-130,580
Derivative Liability, Contract Netting	69,782	115,875
Derivative Liability, Net of Contract Netting	-1,770	-14,705
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	1,770	14,705
Derivative Liability	0	0
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	53,638	107,512
Derivative Liability, Fair Value, Gross Liability	-6,849	0
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Other Current Assets [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	33,183	'
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Other Current Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	0	0
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Deferred Charges And Other Assets [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	20,455	107,512
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Deferred Charges And Other Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	0	0
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Other Current Liabilities [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	0	'
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Other Current Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	0	0
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Deferred Credits And Other Liabilities [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	-6,849	0
Designated As Hedging Instrument [Member] | Natural Gas Distribution Segment [Member] | Deferred Credits And Other Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	0	0
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	9,172	9,510
Derivative Liability, Fair Value, Gross Liability	-5,162	-13,812
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Other Current Assets [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	0	'
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Other Current Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	8,442	9,094
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Deferred Charges And Other Assets [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	0	0
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Deferred Charges And Other Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	730	416
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Other Current Liabilities [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	0	'
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Other Current Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	-3,741	-12,173
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Deferred Credits And Other Liabilities [Member] | Interest Rate Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	0	0
Designated As Hedging Instrument [Member] | Nonregulated Segment [Member] | Deferred Credits And Other Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	-1,421	-1,639
Nondesignated [Member] | Natural Gas Distribution Segment [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	3,508	3,679
Derivative Liability, Fair Value, Gross Liability	-784	-1,543
Nondesignated [Member] | Natural Gas Distribution Segment [Member] | Other Current Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	3,255	1,837
Nondesignated [Member] | Natural Gas Distribution Segment [Member] | Deferred Charges And Other Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	253	1,842
Nondesignated [Member] | Natural Gas Distribution Segment [Member] | Other Current Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	-609	-1,543
Nondesignated [Member] | Natural Gas Distribution Segment [Member] | Deferred Credits And Other Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	-175	0
Nondesignated [Member] | Nonregulated Segment [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	65,718	106,370
Derivative Liability, Fair Value, Gross Liability	-66,390	-116,768
Nondesignated [Member] | Nonregulated Segment [Member] | Other Current Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	45,242	65,388
Nondesignated [Member] | Nonregulated Segment [Member] | Deferred Charges And Other Assets [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	20,476	40,982
Nondesignated [Member] | Nonregulated Segment [Member] | Other Current Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	-51,715	-70,876
Nondesignated [Member] | Nonregulated Segment [Member] | Deferred Credits And Other Liabilities [Member] | Commodity Contract [Member]	'	'
Derivatives Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	($14,675)	($45,892)

Financial_Instruments_Fair_Val

Financial Instruments Fair Value Hedges and Cash Flow Hedges (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Effect of Fair Value Hedges on Results of Operations [Abstract]	'	'	'	'
Commodity contracts	$1,991	$14,453	($2,983)	$3,921
Fair value adjustment for natural gas inventory designated as the hedged item	-2,258	-15,143	4,071	13,261
Total (increase) decrease to purchased gas cost	-267	-690	1,088	17,182
Basis ineffectiveness	817	-2,361	-382	-1,143
Timing ineffectiveness	-1,084	1,671	1,470	18,325
Cash Flow Hedge [Line Items]	'	'	'	'
Gain (loss) reclassified from AOCI into purchased gas cost for effective portion of commodity contracts	4,209	558	8,783	-9,802
Gain (loss) arising from ineffective portion of commodity contracts	179	260	203	158
Total impact on purchased gas cost	4,388	818	8,986	-9,644
Loss on settled Treasury Lock agreements reclassified from AOCI into interest expense	-1,057	-1,057	-3,172	-2,432
Total Impact from Cash Flow Hedges	3,331	-239	5,814	-12,076
Natural Gas Distribution Segment [Member]	'	'	'	'
Cash Flow Hedge [Line Items]	'	'	'	'
Gain (loss) reclassified from AOCI into purchased gas cost for effective portion of commodity contracts	0	0	0	0
Gain (loss) arising from ineffective portion of commodity contracts	0	0	0	0
Total impact on purchased gas cost	0	0	0	0
Loss on settled Treasury Lock agreements reclassified from AOCI into interest expense	-1,057	-1,057	-3,172	-2,432
Total Impact from Cash Flow Hedges	-1,057	-1,057	-3,172	-2,432
Nonregulated Segment [Member]	'	'	'	'
Cash Flow Hedge [Line Items]	'	'	'	'
Gain (loss) reclassified from AOCI into purchased gas cost for effective portion of commodity contracts	4,209	558	8,783	-9,802
Gain (loss) arising from ineffective portion of commodity contracts	179	260	203	158
Total impact on purchased gas cost	4,388	818	8,986	-9,644
Loss on settled Treasury Lock agreements reclassified from AOCI into interest expense	0	0	0	0
Total Impact from Cash Flow Hedges	$4,388	$818	$8,986	($9,644)

Financial_Instruments_Other_Co

Financial Instruments Other Comprehensive Income (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Other Comprehensive Income (Loss), Net of Tax [Abstract]	'		'		'		'
Interest rate agreements fair value	($24,111)		$30,408		($38,559)		$65,308
Forward commodity contracts fair value	96		-3,168		11,805		-1,015
Interest rate agreements	671		671		2,014		1,544
Forward commodity contracts	-2,567		-340		-5,357		5,980
Total other comprehensive income (loss) from hedging, net of tax	-25,911	[1]	27,571	[1]	-30,097	[1]	71,817	[1]
Expected Earnings [Line Items]	'		'		'		'
Interest Rate Agreement Gain (Loss) Reclassified To Earnings	'		'		-28,350	[2]	'
Commodity Contract Gain (Loss) Reclassified To Earnings	'		'		1,972	[2]	'
Total Hedge Gain (Loss) Reclassified To Earnings	'		'		-26,378		'
Next Twelve Months [Member]	'		'		'		'
Expected Earnings [Line Items]	'		'		'		'
Interest Rate Agreement Gain (Loss) Reclassified To Earnings	'		'		-1,317		'
Commodity Contract Gain (Loss) Reclassified To Earnings	'		'		2,407		'
Total Hedge Gain (Loss) Reclassified To Earnings	'		'		1,090		'
Thereafter [Member]	'		'		'		'
Expected Earnings [Line Items]	'		'		'		'
Interest Rate Agreement Gain (Loss) Reclassified To Earnings	'		'		-27,033		'
Commodity Contract Gain (Loss) Reclassified To Earnings	'		'		-435		'
Total Hedge Gain (Loss) Reclassified To Earnings	'		'		($27,468)		'
[1]	Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.
[2]	(1)B Utilizing an income tax rate ranging from 37 percent to 39 percent based on the effective rates in each taxing jurisdiction.

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income Components (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive income (loss), beginning balance	$38,878	($47,607)
Other comprehensive income (loss) before reclassifications	-23,542	64,742
Amounts reclassified from accumulated other comprehensive income	-4,036	6,154
Net current-period other comprehensive income (loss)	-27,578	70,896
Accumulated other comprehensive income (loss), ending balance	11,300	23,289
Accumulated Net Unrealized Investment Gain (Loss) [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive income (loss), beginning balance	5,448	5,661
Other comprehensive income (loss) before reclassifications	3,212	449
Amounts reclassified from accumulated other comprehensive income	-693	-1,370
Net current-period other comprehensive income (loss)	2,519	-921
Accumulated other comprehensive income (loss), ending balance	7,967	4,740
Accumulated Net Gain (Loss) from Interest Rate Hedges [Member] [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive income (loss), beginning balance	37,906	-44,273
Other comprehensive income (loss) before reclassifications	-38,559	65,308
Amounts reclassified from accumulated other comprehensive income	2,014	1,544
Net current-period other comprehensive income (loss)	-36,545	66,852
Accumulated other comprehensive income (loss), ending balance	1,361	22,579
Accumulated Net Gain (Loss) from Commodity Contracts Cash Flow Hedges [Member] [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive income (loss), beginning balance	-4,476	-8,995
Other comprehensive income (loss) before reclassifications	11,805	-1,015
Amounts reclassified from accumulated other comprehensive income	-5,357	5,980
Net current-period other comprehensive income (loss)	6,448	4,965
Accumulated other comprehensive income (loss), ending balance	$1,972	($4,030)

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income Affected Line Item in the Statement of Income (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Operation and maintenance	($125,559)	($121,258)	($365,991)	($338,871)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	74,391	53,188	427,827	356,845
Income Tax Expense	-28,670	-19,714	-161,723	-133,683
Income (loss) from continuing operations	45,721	33,474	266,104	223,162
Interest charges	-31,840	-32,741	-95,556	-96,594
Purchased gas cost	-583,185	-541,438	-2,917,421	-2,089,476
Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Income (loss) from continuing operations	2,362	-669	4,036	-6,154
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Operation and maintenance	733	-531	1,091	2,158
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	733	-531	1,091	2,158
Income Tax Expense	-267	193	-398	-788
Income (loss) from continuing operations	466	-338	693	1,370
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Interest Rate Hedges [Member] [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Interest charges	-1,057	-1,057	-3,172	-2,432
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Commodity Contracts Cash Flow Hedges [Member] [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Purchased gas cost	4,209	558	8,783	-9,803
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	3,152	-499	5,611	-12,235
Income Tax Expense	-1,256	168	-2,268	4,711
Income (loss) from continuing operations	$1,896	($331)	$3,343	($7,524)

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	Jun. 30, 2014	Sep. 30, 2013
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	$70,173,000	$121,320,000
Hedged portion of gas stored underground	39,191,000	44,758,000
Available-for-sale Securities	80,910,000	72,682,000
Total assets	190,274,000	238,760,000
Financial instruments, liabilities	7,633,000	1,543,000
Fair Value [Abstract]	'	'
Derivative, Cash Collateral	9,700,000	24,800,000
Cash Held In Margin Accounts Classified Current Risk Management Asset	7,900,000	10,100,000
Cash Held In Margin Accounts Offset Current Risk Management Liabilities	1,800,000	14,700,000
Debt Instrument Carrying Amount	2,460,000,000	2,460,000,000
Debt Instrument Fair Value	2,795,188,000	2,676,487,000
Money Market Funds [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	1,959,000	4,428,000
Equity Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	45,554,000	40,094,000
Debt Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	33,397,000	28,160,000
Natural Gas Distribution Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	57,146,000	111,191,000
Financial instruments, liabilities	7,633,000	1,543,000
Fair Value [Abstract]	'	'
Cash Held In Margin Accounts Classified Current Risk Management Asset	0	0
Cash Held In Margin Accounts Offset Current Risk Management Liabilities	0	0
Nonregulated Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	13,027,000	10,129,000
Financial instruments, liabilities	0	0
Fair Value [Abstract]	'	'
Cash Held In Margin Accounts Classified Current Risk Management Asset	7,919,000	10,124,000
Cash Held In Margin Accounts Offset Current Risk Management Liabilities	1,770,000	14,705,000
Fair Value Inputs Level 1 [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	3,000	745,000
Hedged portion of gas stored underground	39,191,000	44,758,000
Available-for-sale Securities	45,554,000	40,094,000
Total assets	84,748,000	85,597,000
Financial instruments, liabilities	108,000	158,000
Fair Value Inputs Level 1 [Member] | Money Market Funds [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Fair Value Inputs Level 1 [Member] | Equity Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	45,554,000	40,094,000
Fair Value Inputs Level 1 [Member] | Debt Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Fair Value Inputs Level 1 [Member] | Natural Gas Distribution Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	0	0
Financial instruments, liabilities	0	0
Fair Value Inputs Level 1 [Member] | Nonregulated Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	3,000	745,000
Financial instruments, liabilities	108,000	158,000
Fair Value Inputs Level 2 [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	132,033,000	226,326,000
Hedged portion of gas stored underground	0	0
Available-for-sale Securities	35,356,000	32,588,000
Total assets	167,389,000	258,914,000
Financial instruments, liabilities	79,077,000	131,965,000
Fair Value Inputs Level 2 [Member] | Money Market Funds [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	1,959,000	4,428,000
Fair Value Inputs Level 2 [Member] | Equity Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Fair Value Inputs Level 2 [Member] | Debt Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	33,397,000	28,160,000
Fair Value Inputs Level 2 [Member] | Natural Gas Distribution Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	57,146,000	111,191,000
Financial instruments, liabilities	7,633,000	1,543,000
Fair Value Inputs Level 2 [Member] | Nonregulated Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	74,887,000	115,135,000
Financial instruments, liabilities	71,444,000	130,422,000
Fair Value Inputs Level 3 [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	0	0
Hedged portion of gas stored underground	0	0
Available-for-sale Securities	0	0
Total assets	0	0
Financial instruments, liabilities	0	0
Fair Value Inputs Level 3 [Member] | Money Market Funds [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Fair Value Inputs Level 3 [Member] | Equity Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Fair Value Inputs Level 3 [Member] | Debt Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Fair Value Inputs Level 3 [Member] | Natural Gas Distribution Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	0	0
Financial instruments, liabilities	0	0
Fair Value Inputs Level 3 [Member] | Nonregulated Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	0	0
Financial instruments, liabilities	0	0
Netting And Collateral [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	-61,863,000	-105,751,000
Hedged portion of gas stored underground	0	0
Available-for-sale Securities	0	0
Total assets	-61,863,000	-105,751,000
Financial instruments, liabilities	-71,552,000	-130,580,000
Netting And Collateral [Member] | Money Market Funds [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Netting And Collateral [Member] | Equity Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Netting And Collateral [Member] | Debt Securities [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities	0	0
Netting And Collateral [Member] | Natural Gas Distribution Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	0	0
Financial instruments, liabilities	0	0
Netting And Collateral [Member] | Nonregulated Segment [Member]	'	'
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]	'	'
Financial instruments, assets	-61,863,000	-105,751,000
Financial instruments, liabilities	($71,552,000)	($130,580,000)

Fair_Value_Measurements_Availa

Fair Value Measurements Available-For-Sale Securities (Details) (USD $)	9 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013
Schedule Of Available For Sale Securities [Line Items]	'	'	'
Available For Sale Securities Amortized Cost	$68,214,000	'	$64,023,000
Gross Unrealized Gain	12,699,000	'	8,706,000
Gross Unrealized Loss	-3,000	'	-47,000
Fair value	80,910,000	'	72,682,000
Available-for-sale Securities, Other Disclosure Items [Abstract]	'	'	'
Available-for-sale Securities, Supplemental Executive Benefit Plans	47,500,000	'	44,500,000
Available-for-sale Securities, Gross Realized Gains	1,100,000	2,200,000	'
Equity Funds Domestic [Member]	'	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'	'
Available For Sale Securities Amortized Cost	27,983,000	'	27,043,000
Gross Unrealized Gain	10,274,000	'	7,476,000
Gross Unrealized Loss	0	'	-23,000
Fair value	38,257,000	'	34,496,000
Equity Funds Foreign [Member]	'	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'	'
Available For Sale Securities Amortized Cost	5,092,000	'	4,536,000
Gross Unrealized Gain	2,205,000	'	1,062,000
Gross Unrealized Loss	0	'	0
Fair value	7,297,000	'	5,598,000
Debt Securities [Member]	'	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'	'
Available For Sale Securities Amortized Cost	33,180,000	'	28,016,000
Gross Unrealized Gain	220,000	'	168,000
Gross Unrealized Loss	-3,000	'	-24,000
Fair value	33,397,000	'	28,160,000
Money Market Funds [Member]	'	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'	'
Available For Sale Securities Amortized Cost	1,959,000	'	4,428,000
Gross Unrealized Gain	0	'	0
Gross Unrealized Loss	0	'	0
Fair value	$1,959,000	'	$4,428,000

Discontinued_Operations_Detail

Discontinued Operations (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Apr. 02, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Discontinued Operations and Disposal Groups [Abstract]	'	'	'	'	'
Discontinued Operation, Cash Price Received from Disposal of Discontinued Operation	$153,000,000	'	'	'	'
Discontinued Operation, Income (Loss) from Discontinued Operation Disclosures [Abstract]	'	'	'	'	'
Operating revenues	'	0	0	0	37,962,000
Purchased gas cost	'	0	0	0	21,464,000
Gross profit	'	0	0	0	16,498,000
Operating expenses	'	0	0	0	5,858,000
Operating income	'	0	0	0	10,640,000
Miscellaneous income (expense)	'	0	0	0	548,000
Income from discontinued operations before income taxes	'	0	0	0	11,188,000
Income tax expense	'	0	0	0	3,986,000
Income (loss) from discontinued operations	'	0	0	0	7,202,000
Gain (loss) on sale of discontinued operations, net of tax	5,300,000	0	5,294,000	0	5,294,000
Net income (loss) from discontinued operations	'	$0	$5,294,000	$0	$12,496,000