STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Operating activities
Net income	$ 83,491	$ 71,284
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	81,253	79,094
Demand side management program amortization	1,358	1,573
Deferred income taxes	56,476	26,520
Amortization of investment tax credits	(255)	(223)
Allowance for equity funds used during construction	(4,178)	(2,529)
Net realized and unrealized hedging and derivative transactions	201	201
Changes in operating assets and liabilities:
Accounts receivable	(37,089)	(25,352)
Accrued unbilled revenues	(3,013)	(12,666)
Inventories	(4,732)	(5,734)
Prepayments and other	(1,655)	11,468
Accounts payable	(6,129)	(19,399)
Net regulatory assets and liabilities	7,327	(19,274)
Other current liabilities	17,530	16,240
Change in other noncurrent assets	1,101	(2,838)
Change in other noncurrent liabilities	(11,223)	(2,111)
Net cash provided by operating activities	180,463	116,254
Investing activities
Utility capital/construction expenditures	(224,864)	(196,035)
Allowance for equity funds used during construction	4,178	2,529
Investments in utility money pool arrangement	0	(204,200)
Repayments from utility money pool arrangement	0	281,200
Other investments	221	0
Net cash used in investing activities	(220,465)	(116,506)
Financing activities
Repayment of short-term borrowings, net	(49,000)	0
Proceeds from issuance of long-term debt	193,149	0
Repayment of long-term debt	(101,800)	(25,000)
Borrowings under utility money pool arrangement	283,500	61,000
Repayments under utility money pool arrangement	(283,500)	0
Capital contributions from parent	90,000	8,802
Dividends paid to parent	(64,401)	(50,810)
Net cash provided by (used in) financing activities	67,948	(6,008)
Net increase (decrease) in cash and cash equivalents	27,946	(6,260)
Cash and cash equivalents at beginning of period	1,778	7,363
Cash and cash equivalents at end of period	29,724	1,103
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(30,927)	(43,963)
Cash paid for income taxes, net	(192)	(8,310)
Supplemental disclosure of non-cash investing transactions:
Property, plant and equipment additions in accounts payable	$ 7,012	$ 4,075