Statement of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 141.6	$ 133.7	$ 133.1
Adjustments to reconcile net income to cash from operating activities:
Depreciation and amortization	244.3	229.1	211.9
Deferred income taxes and investment tax credits	71.7	69.3	84.9
Equity in (earnings) losses of unconsolidated affiliates	32.0	8.6	(3.4)
Provision for uncollectible accounts	11.8	16.8	15.1
Expense portion of pension and postretirement benefit cost	9.0	10.0	10.4
Gain on sale of business in 2011, net of other non-cash charges	(0.1)	15.9	13.3
Changes in working capital accounts:
Accounts receivable and accrued unbilled revenue	(17.5)	(48.3)	96.9
Inventories	(26.1)	(19.3)	(36.1)
Recoverable/refundable fuel and natural gas costs	(4.5)	(30.2)	21.3
Prepayments and other current assets	17.9	(23.5)	43.1
Accounts payable, including to affiliated companies	(21.2)	5.5	(85.8)
Accrued liabilities	6.4	10.2	4.0
Unconsolidated affiliate dividends	0.1	42.7	12.6
Employer contributions to pension and postretirement plans	(38.8)	(22.0)	(38.5)
Changes in noncurrent assets	0.3	(7.6)	0.2
Changes in noncurrent liabilities	(10.0)	(6.1)	(33.4)
Net cash flows from operating activities	416.9	384.8	449.6
Proceeds from:
Long-term debt, net of issuance costs	148.9	124.2	312.5
Dividend reinvestment plan and other common stock issuances	7.9	14.0	5.8
Requirements for:
Dividends on common stock	(113.2)	(110.8)	(108.6)
Retirement of long-term debt	(349.1)	(49.3)	(3.5)
Other financing activities	(2.3)	(0.2)	0
Net change in short-term borrowings	208.8	(95.2)	(306.0)
Net cash flows from financing activities	(99.0)	(117.3)	(99.8)
Proceeds from:
Sale of business	84.3	0	0
Unconsolidated affiliate distributions	0.5	0.5	4.6
Other collections	1.1	10.8	1.5
Requirements for:
Capital expenditures, excluding AFUDC equity	(321.3)	(277.2)	(432.0)
Business acquisition, net of cash acquired	(83.4)	0	0
Other investments	(0.9)	(3.1)	(5.2)
Net cash flows from investing activities	(319.7)	(269.0)	(431.1)
Net change in cash and cash equivalents	(1.8)	(1.5)	(81.3)
Cash and cash equivalents at beginning of period	10.4	11.9	93.2
Cash and cash equivalents at end of period	$ 8.6	$ 10.4	$ 11.9

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).