Segment Information (Table)

12 Months Ended

Sep. 30, 2016

Segment Reporting [Abstract]

Schedule of segment reporting income statement, by segment

Summarized income statements and capital expenditures by segment are shown in the following tables.

	Year Ended September 30, 2016
	Regulated Distribution		Regulated Pipeline			Nonregulated		Eliminations			Consolidated
	(In thousands)
Operating revenues from external parties	$	2,284,185	$	104,007		$	961,757	$	—		$	3,349,949
Intersegment revenues	7,681		304,826			104,606		(417,113		)	—
	2,291,866		408,833			1,066,363		(417,113		)	3,349,949
Purchased gas cost	1,019,061		—			1,002,573		(416,581		)	1,605,053
Gross profit	1,272,805		408,833			63,790		(532		)	1,744,896
Operating expenses
Operation and maintenance	404,115		129,525			27,658		(532		)	560,766
Depreciation and amortization	233,036		55,576			4,484		—			293,096
Taxes, other than income	196,070		24,298			2,648		—			223,016
Total operating expenses	833,221		209,399			34,790		(532		)	1,076,878
Operating income	439,584		199,434			29,000		—			668,018
Miscellaneous income (expense)	455		(1,683		)	1,443		(1,808		)	(1,593		)
Interest charges	79,404		36,574			1,778		(1,808		)	115,948
Income before income taxes	360,635		161,177			28,665		—			550,477
Income tax expense	128,265		59,488			12,620		—			200,373
Net income	$	232,370	$	101,689		$	16,045	$	—		$	350,104
Capital expenditures	$	740,039	$	346,400		$	511	$	—		$	1,086,950

	Year Ended September 30, 2015
	Regulated Distribution			Regulated Pipeline			Nonregulated			Eliminations			Consolidated
	(In thousands)
Operating revenues from external parties	$	2,757,585		$	97,662		$	1,286,889		$	—		$	4,142,136
Intersegment revenues	6,250			272,450			185,320			(464,020		)	—
	2,763,835			370,112			1,472,209			(464,020		)	4,142,136
Purchased gas cost	1,526,258			—			1,399,349			(463,488		)	2,462,119
Gross profit	1,237,577			370,112			72,860			(532		)	1,680,017
Operating expenses
Operation and maintenance	388,486			118,866			35,048			(532		)	541,868
Depreciation and amortization	223,048			47,236			4,512			—			274,796
Taxes, other than income	205,894			22,743			3,321			—			231,958
Total operating expenses	817,428			188,845			42,881			(532		)	1,048,622
Operating income	420,149			181,267			29,979			—			631,395
Miscellaneous expense	(377		)	(1,243		)	(760		)	(2,009		)	(4,389		)
Interest charges	84,132			33,151			967			(2,009		)	116,241
Income before income taxes	335,640			146,873			28,252			—			510,765
Income tax expense	130,827			52,211			12,652			—			195,690
Net income	$	204,813		$	94,662		$	15,600		$	—		$	315,075
Capital expenditures	$	670,575		$	291,603		$	1,443		$	—		$	963,621

	Year Ended September 30, 2014
	Regulated Distribution			Regulated Pipeline			Nonregulated		Eliminations			Consolidated
	(In thousands)
Operating revenues from external parties	$	3,056,212		$	92,166		$	1,792,538	$	—		$	4,940,916
Intersegment revenues	5,334			226,293			274,754		(506,381		)	—
	3,061,546			318,459			2,067,292		(506,381		)	4,940,916
Purchased gas cost	1,885,031			—			1,979,337		(505,878		)	3,358,490
Gross profit	1,176,515			318,459			87,955		(503		)	1,582,426
Operating expenses
Operation and maintenance	387,228			91,466			26,963		(503		)	505,154
Depreciation and amortization	208,376			41,031			4,580		—			253,987
Taxes, other than income	196,343			13,143			2,450		—			211,936
Total operating expenses	791,947			145,640			33,993		(503		)	971,077
Operating income	384,568			172,819			53,962		—			611,349
Miscellaneous income (expense)	(381		)	(3,181		)	2,216		(3,889		)	(5,235		)
Interest charges	94,918			36,280			1,986		(3,889		)	129,295
Income before income taxes	289,269			133,358			54,192		—			476,819
Income tax expense	117,684			47,167			22,151		—			187,002
Net income	$	171,585		$	86,191		$	32,041	$	—		$	289,817
Capital expenditures	$	574,372		$	248,230		$	1,839	$	—		$	824,441

Revenue from External Customers by Products and Services

The following table summarizes our revenues from external parties by products and services for the fiscal year ended September 30.

	2016		2015		2014
	(In thousands)
Regulated distribution revenues:
Gas sales revenues:
Residential	$	1,477,049	$	1,761,689	$	1,933,099
Commercial	619,979		772,187		876,042
Industrial	51,999		74,981		90,536
Public authority and other	41,307		53,401		64,779
Total gas sales revenues	2,190,334		2,662,258		2,964,456
Transportation revenues	70,383		67,475		64,049
Other gas revenues	23,468		27,852		27,707
Total regulated distribution revenues	2,284,185		2,757,585		3,056,212
Regulated pipeline revenues	104,007		97,662		92,166
Nonregulated revenues	961,757		1,286,889		1,792,538
Total operating revenues	$	3,349,949	$	4,142,136	$	4,940,916

Schedule of segment reporting balance sheet information, by segment

Balance sheet information at September 30, 2016 and 2015 by segment is presented in the following tables.

	September 30, 2016
	Regulated Distribution		Regulated Pipeline		Nonregulated		Eliminations			Consolidated
	(In thousands)
ASSETS
Property, plant and equipment, net	$	6,220,425	$	2,008,997	$	51,089	$	—		$	8,280,511
Investment in subsidiaries	1,026,859		—		—		(1,026,859		)	—
Current assets
Cash and cash equivalents	21,072		—		26,462		—			47,534
Assets from risk management activities	3,029		—		6,775		—			9,804
Other current assets	446,868		19,204		367,220		(208,944		)	624,348
Intercompany receivables	978,093		—		—		(978,093		)	—
Total current assets	1,449,062		19,204		400,457		(1,187,037		)	681,686
Goodwill	576,114		132,582		34,711		—			743,407
Noncurrent assets from risk management activities	1,822		—		—		—			1,822
Deferred charges and other assets	275,496		27,631		336		—			303,463
	$	9,549,778	$	2,188,414	$	486,593	$	(2,213,896	)	$	10,010,889
CAPITALIZATION AND LIABILITIES
Shareholders’ equity	$	3,463,059	$	678,964	$	347,895	$	(1,026,859	)	$	3,463,059
Long-term debt	2,188,779		—		—		—			2,188,779
Total capitalization	5,651,838		678,964		347,895		(1,026,859		)	5,651,838
Current liabilities
Current maturities of long-term debt	250,000		—		—		—			250,000
Short-term debt	1,026,811		—		—		(197,000		)	829,811
Liabilities from risk management activities	56,771		—		—		—			56,771
Other current liabilities	549,328		22,427		91,888		(11,944		)	651,699
Intercompany payables	—		950,215		27,878		(978,093		)	—
Total current liabilities	1,882,910		972,642		119,766		(1,187,037		)	1,788,281
Deferred income taxes	1,058,895		536,732		7,429		—			1,603,056
Noncurrent liabilities from risk management activities	184,048		—		—		—			184,048
Regulatory cost of removal obligation	424,281		—		—		—			424,281
Pension and postretirement liabilities	297,743		—		—		—			297,743
Deferred credits and other liabilities	50,063		76		11,503		—			61,642
	$	9,549,778	$	2,188,414	$	486,593	$	(2,213,896	)	$	10,010,889

	September 30, 2015
	Regulated Distribution		Regulated Pipeline		Nonregulated			Eliminations			Consolidated
	(In thousands)
ASSETS
Property, plant and equipment, net	$	5,670,306	$	1,706,449	$	53,825		$	—		$	7,430,580
Investment in subsidiaries	1,038,670		—		(2,096		)	(1,036,574		)	—
Current assets
Cash and cash equivalents	23,863		—		4,790			—			28,653
Assets from risk management activities	378		—		8,854			—			9,232
Other current assets	421,591		24,628		480,503			(338,301		)	588,421
Intercompany receivables	887,713		—		—			(887,713		)	—
Total current assets	1,333,545		24,628		494,147			(1,226,014		)	626,306
Goodwill	575,449		132,542		34,711			—			742,702
Noncurrent assets from risk management activities	368		—		—			—			368
Deferred charges and other assets	252,499		17,288		5,329			—			275,116
	$	8,870,837	$	1,880,907	$	585,916		$	(2,262,588	)	$	9,075,072
CAPITALIZATION AND LIABILITIES
Shareholders’ equity	$	3,194,797	$	577,275	$	461,395		$	(1,038,670	)	$	3,194,797
Long-term debt	2,437,515		—		—			—			2,437,515
Total capitalization	5,632,312		577,275		461,395			(1,038,670		)	5,632,312
Current liabilities
Short-term debt	782,927		—		—			(325,000		)	457,927
Liabilities from risk management activities	9,568		—		—			—			9,568
Other current liabilities	569,273		29,780		99,480			(11,205		)	687,328
Intercompany payables	—		867,409		20,304			(887,713		)	—
Total current liabilities	1,361,768		897,189		119,784			(1,223,918		)	1,154,823
Deferred income taxes	1,008,091		406,254		(3,030		)	—			1,411,315
Noncurrent liabilities from risk management activities	110,539		—		—			—			110,539
Regulatory cost of removal obligation	427,553		—		—			—			427,553
Pension and postretirement liabilities	287,373		—		—			—			287,373
Deferred credits and other liabilities	43,201		189		7,767			—			51,157
	$	8,870,837	$	1,880,907	$	585,916		$	(2,262,588	)	$	9,075,072