Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating Activities:
Net Income	$ 16.4	$ 9.6	$ 10.0
Adjustments to Reconcile Net Income to Cash Provided by Operating Activities:
Depreciation and Amortization	29.3	28.9	27.4
Deferred Taxes Provision	8.7	10.5	7.1
Changes in Working Capital Items:
Accounts Receivable	(7.3)	(3.4)	6.2
Accrued Revenue	(9.9)	(2.7)	12.9
Taxes Refundable / Payable	8.5	(5.8)	1.5
Gas Inventory	(4.2)	3.7	17.3
Accounts Payable	(0.1)	1.4	(3.4)
Other Changes in Working Capital Items	(0.7)	(5.3)	(5.1)
Deferred Regulatory and Other Charges	7.5	(4.5)	(26.0)
Other, net	(2.3)	(6.5)	3.0
Cash Provided by Operating Activities	45.9	25.9	50.9
Investing Activities:
Property, Plant and Equipment Additions	(57.1)	(49.6)	(58.7)
Acquisitions, net (See Note 2)			(6.9)
Cash (Used In) Investing Activities	(57.1)	(49.6)	(65.6)
Financing Activities:
Proceeds from (Repayment of) Short-Term Debt, net	21.1	2.3	(9.6)
Proceeds from Issuance (Repayment) of Long-Term Debt, net	(0.5)	39.5	(0.4)
Net Increase (Decrease) in Gas Inventory Financing	4.6	(2.2)	(21.8)
Dividends Paid	(15.2)	(15.0)	(13.2)
Proceeds from Issuance of Common Stock	1.0	0.9	56.4
Other, net	(1.2)	(0.6)	(0.5)
Cash Provided by Financing Activities	9.8	24.9	10.9
Net Increase (Decrease) in Cash	(1.4)	1.2	(3.8)
Cash at Beginning of Year	8.9	7.7	11.5
Cash at End of Year	7.5	8.9	7.7
Supplemental Information:
Interest Paid	21.2	20.5	19.3
Income Taxes (Refunded) Paid	$ (7.3)	$ 2.3	$ (3.8)

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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).