STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating activities
Net income	$ 99,901	$ 83,491
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	86,426	81,253
Demand side management program amortization	1,358	1,358
Deferred income taxes	36,600	56,476
Amortization of investment tax credits	(206)	(255)
Allowance for equity funds used during construction	(5,062)	(4,178)
Net derivative losses	201	201
Changes in operating assets and liabilities:
Accounts receivable	(21,406)	(37,089)
Accrued unbilled revenues	(8,593)	(3,013)
Inventories	3,601	(4,732)
Prepayments and other	1,204	(1,655)
Accounts payable	(21,834)	(6,129)
Net regulatory assets and liabilities	44,031	7,327
Other current liabilities	25,664	17,530
Pension and other employee benefit obligations	(10,527)	(5,634)
Change in other noncurrent assets	(1,577)	1,101
Change in other noncurrent liabilities	(656)	(5,589)
Net cash provided by operating activities	229,125	180,463
Investing activities
Utility capital/construction expenditures	(275,253)	(224,864)
Allowance for equity funds used during construction	5,062	4,178
Investments in utility money pool arrangement	(134,000)	0
Repayments from utility money pool arrangement	134,000	0
Other, net	0	221
Net cash used in investing activities	(270,191)	(220,465)
Financing activities
Repayment of short-term borrowings, net	0	(49,000)
Proceeds from issuance of long-term debt	108,691	193,149
Repayment of long-term debt	0	(101,800)
Borrowings under utility money pool arrangement	240,000	283,500
Repayments under utility money pool arrangement	(245,000)	(283,500)
Capital contributions from parent	3,811	90,000
Dividends paid to parent	(50,089)	(64,401)
Net cash provided by financing activities	57,413	67,948
Net change in cash and cash equivalents	16,347	27,946
Cash and cash equivalents at beginning of period	650	1,778
Cash and cash equivalents at end of period	16,997	29,724
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(35,345)	(30,927)
Cash paid for income taxes, net	(14,391)	(192)
Supplemental disclosure of non-cash investing transactions:
Property, plant and equipment additions in accounts payable	$ 28,886	$ 7,012