Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Operating Activities:
Net Income	$ 9.0	$ 8.7
Adjustments to Reconcile Net Income to Cash Provided by Operating Activities:
Depreciation and Amortization	8.3	7.9
Deferred Tax Provision	5.3	4.5
Changes in Working Capital Items:
Accounts Receivable	(3.7)	(8.8)
Accrued Revenue	19.2	12.8
Taxes Refundable / Payable	(0.6)	7.6
Gas Inventory	8.0	9.9
Accounts Payable	(7.7)	(4.0)
Other Changes in Working Capital Items	(1.7)	(0.2)
Deferred Regulatory and Other Charges	(4.2)	(2.5)
Other, net	(1.5)	0.5
Cash Provided by Operating Activities	30.4	36.4
Investing Activities:
Property, Plant and Equipment Additions	(9.1)	(10.8)
Cash (Used in) Investing Activities	(9.1)	(10.8)
Financing Activities:
Repayment of Short-Term Debt	(10.3)	(16.2)
Repayment of Long-Term Debt	(0.1)	(0.1)
Net Decrease in Gas Inventory Financing	(6.5)	(7.8)
Dividends Paid	(3.8)	(3.8)
Proceeds from Issuance of Common Stock	0.3	0.3
Other, net	(0.2)	(0.3)
Cash (Used in) Financing Activities	(20.6)	(27.9)
Net Increase (Decrease) in Cash	0.7	(2.3)
Cash at Beginning of Period	7.5	8.9
Cash at End of Period	8.2	6.6
Supplemental Cash Flow Information:
Interest Paid	3.1	3.1
Income Taxes Paid (Refunded)	$ 0.6	$ (6.9)

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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).