Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 44,265	$ 23,351
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	17,391	16,701
Deferred income tax expense	14,049	15,607
Provision for uncollectible accounts	2,442	1,930
Other, net	4,117	4,331
Net change in:
Accounts receivable and accrued utility revenues	(99,289)	(46,757)
Inventories	2,647	2,351
Deferred fuel and power costs, net of changes in unsettled derivatives	(1,000)	(6,788)
Accounts payable	19,358	(3,642)
Other current assets	(4,122)	(4,767)
Other current liabilities	4,888	6,449
Net cash provided by operating activities	4,746	8,766
CASH FLOWS FROM INVESTING ACTIVITIES
Expenditures for property, plant and equipment	(69,639)	(60,457)
Net costs of property, plant and equipment disposals	(4,061)	(3,150)
Decrease in restricted cash	583	278
Net cash used by investing activities	(73,117)	(63,329)
CASH FLOWS FROM FINANCING ACTIVITIES
Payments of dividends	(10,000)	(7,000)
Issuances of long-term debt, net of issuance costs	99,490	0
Repayments of long-term debt	0	(72,000)
(Decrease) increase in short-term borrowings	(14,100)	146,000
Other	0	49
Net cash provided by financing activities	75,390	67,049
Cash and cash equivalents increase	7,019	12,486
CASH AND CASH EQUIVALENTS
End of period	9,838	15,585
Beginning of period	2,819	3,099
Increase	$ 7,019	$ 12,486