Business Segment Information (Tables)

9 Months Ended

Jun. 30, 2018

Segment Reporting [Abstract]

Financial Segment Information By Segment

Quarter Ended June 30, 2018 (Thousands)
	Exploration and Production	Pipeline and Storage	Gathering	Utility	Energy Marketing	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
Revenue from External Customers	$135,828	$51,363	$(31)	$128,628	$25,460	$341,248	$1,496	$168	$342,912
Intersegment Revenues	$—	$22,496	$27,908	$3,519	$512	$54,435	$—	$(54,435)	$—
Segment Profit: Net Income (Loss)	$27,817	$20,723	$11,566	$3,930	$(190)	$63,846	$297	$(1,118)	$63,025

Nine Months Ended June 30, 2018 (Thousands)
	Exploration and Production	Pipeline and Storage	Gathering	Utility	Energy Marketing	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
Revenue from External Customers	$421,381	$158,387	$41	$599,495	$119,739	$1,299,043	$3,824	$606	$1,303,473
Intersegment Revenues	$—	$67,524	$79,404	$11,401	$589	$158,918	$—	$(158,918)	$—
Segment Profit: Net Income (Loss)	$161,052	$81,909	$68,736	$58,283	$1,434	$371,414	$(214)	$(17,673)	$353,527

(Thousands)	Exploration and Production	Pipeline and Storage	Gathering	Utility	Energy Marketing	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
Segment Assets:
At June 30, 2018	$1,591,783	$1,763,620	$534,086	$1,904,189	$51,778	$5,845,456	$77,879	$50,768	$5,974,103
At September 30, 2017	$1,407,152	$1,929,788	$580,051	$2,013,123	$60,937	$5,991,051	$76,861	$35,408	$6,103,320

Quarter Ended June 30, 2017 (Thousands)
	Exploration and Production	Pipeline and Storage	Gathering	Utility	Energy Marketing	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
Revenue from External Customers	$151,161	$50,049	$34	$121,900	$24,460	$347,604	$538	$226	$348,368
Intersegment Revenues	$—	$21,643	$26,853	$3,391	$565	$52,452	$—	$(52,452)	$—
Segment Profit: Net Income (Loss)	$30,123	$16,031	$10,107	$4,348	$(564)	$60,045	$(98)	$(233)	$59,714

Nine Months Ended June 30, 2017 (Thousands)
	Exploration and Production	Pipeline and Storage	Gathering	Utility	Energy Marketing	Total Reportable Segments	All Other	Corporate and Intersegment Eliminations	Total Consolidated
Revenue from External Customers	$471,646	$156,212	$86	$550,819	$112,210	$1,290,973	$1,311	$660	$1,292,944
Intersegment Revenues	$—	$66,389	$82,629	$11,314	$600	$160,932	$—	$(160,932)	$—
Segment Profit: Net Income (Loss)	$98,972	$54,656	$31,373	$51,103	$2,122	$238,226	$(498)	$178	$237,906