CONSOLIDATED STATEMENT OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 101,572	$ 108,810
Adjustments to reconcile net income to cash flows from operating activities:
Unrealized loss on derivative instruments	17,596	53,503
Depreciation and amortization	30,726	25,445
Allowance for equity used during construction	(317)	(1,252)
Allowance for bad debt expense	1,989	3,365
Deferred income taxes	30,588	22,110
Manufactured gas plant remediation costs	(6,125)	(10,818)
Equity in earnings of affiliates, net of distributions received	4,209	(470)
Cost of removal - asset retirement obligations	(912)	(711)
Contributions to postemployment benefit plans	(24,446)	(9,591)
Changes in:
Components of working capital	(110,114)	5,311
Other noncurrent assets	8,747	11,951
Other noncurrent liabilities	6,404	19,568
Cash flows from operating activities	59,917	227,221
CASH FLOWS (USED IN) INVESTING ACTIVITIES
Utility plant expenditures	(71,916)	(69,894)
Solar equipment expenditures	(75,243)	(17,529)
Real estate properties and other expenditures	(568)	(2,423)
Cost of removal expenditures	(10,634)	(8,075)
Withdrawal from restricted cash construction fund	126	67
Cash flows (used in) investing activities	(158,235)	(97,854)
CASH FLOWS FROM (USED IN) FINANCING ACTIVITIES
Proceeds from issuance of common stock	10,636	10,507
Tax benefit from stock options exercised	222	355
Proceeds from sale-leaseback transaction	6,522	5,901
Payments of long-term debt	(4,856)	(25,690)
Purchases of treasury stock	(8,768)	(7,222)
Payments of common stock dividends	(46,466)	(43,747)
Net proceeds from short-term debt	140,650	(9,600)
Cash flows from (used in) financing activities	97,940	(69,496)
Change in cash and cash equivalents	(378)	59,871
Cash and cash equivalents at beginning of period	7,440	943
Cash and cash equivalents at end of period	7,062	60,814
CHANGES IN COMPONENTS OF WORKING CAPITAL
Receivables	36,598	(97,566)
Inventories	78,601	87,210
Recovery of gas costs	(13,405)	36,329
Gas purchases payable	(99,173)	12,856
Prepaid and accrued taxes	(11,375)	15,654
Accounts payable and other	9,754	11,857
Restricted broker margin accounts	(20,320)	(36,544)
Customers' credit balances and deposits	(75,318)	(16,341)
Other current assets	(15,476)	(8,144)
Components of working capital	(110,114)	5,311
SUPPLEMENTAL DISCLOSURES OF CASH FLOWS INFORMATION
Cash paid for Interest (net of amounts capitalized)	8,918	9,778
Cash paid for Income taxes	7,536	4,138
SUPPLEMENTAL SCHEDULE OF NONCASH INVESTING ACTIVITIES
Accrued Capital Expenditures	$ (108)	$ (4,245)