Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ (5,808)	$ 3,458
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization of electric plant in service	23,293	21,565
Amortization of nuclear fuel	11,800	11,392
Deferred income taxes, net	(3,632)	6,255
Allowance for equity funds used during construction	(2,336)	(4,275)
Other amortization and accretion	4,250	4,499
Gain on sale of property, plant and equipment	(545)	0
Net gains on sale of decommissioning trust funds	(1,388)	(3,745)
Other operating activities	124	132
Change in:
Accounts receivable	8,296	5,828
Inventories	1,302	(1,190)
Net over-collection of fuel revenues	4,104	15,687
Prepayments and other	(2,975)	(2,691)
Accounts payable	(21,827)	(24,230)
Taxes accrued	(5,127)	(8,825)
Interest accrued	6,703	4,114
Other current liabilities	835	(910)
Deferred charges and credits	(3,134)	(612)
Net cash provided by operating activities	13,935	26,452
Cash flows from investing activities:
Cash additions to utility property, plant and equipment	(52,675)	(73,865)
Cash additions to nuclear fuel	(11,220)	(10,183)
Capitalized interest and AFUDC:
Utility property, plant and equipment	(3,994)	(6,896)
Nuclear fuel	(1,242)	(1,289)
Allowance for equity funds used during construction	2,336	4,275
Decommissioning trust funds:
Purchases, including funding of $1.1 million	(26,544)	(26,961)
Sales and maturities	24,078	24,642
Proceeds from sale of property, plant and equipment	596	0
Other investing activities	(750)	(230)
Net cash used for investing activities	(69,415)	(90,507)
Cash flows from financing activities:
Dividends paid	(11,928)	(11,303)
Borrowings under the revolving credit facility:
Proceeds	97,655	70,852
Payments	(152,343)	(27,039)
Proceeds from issuance of senior notes	157,052	0
Other financing activities	(1,793)	(985)
Net cash provided by financing activities	88,643	31,525
Net increase (decrease) in cash and cash equivalents	33,163	(32,530)
Cash and cash equivalents at beginning of period	8,149	40,504
Cash and cash equivalents at end of period	$ 41,312	$ 7,974