Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities:
Net Income	$ 21.6	$ 18.2	$ 16.4
Adjustments to Reconcile Net Income to Cash Provided by Operating Activities:
Depreciation and Amortization	37.7	35.1	29.3
Deferred Taxes Provision	12.3	10.8	8.7
Changes in Working Capital Items:
Accounts Receivable	(4.5)	(2.6)	(7.4)
Accrued Revenue	6.8	(0.7)	(7.7)
Regulatory Liabilities	2.9	(4.4)	5.0
Taxes Refundable / Payable	(0.5)	(0.3)	8.5
Exchange Gas Receivable	(1.4)	4.1	(4.3)
Accounts Payable	5.4	5.4
Other Changes in Working Capital Items	(2.9)	(0.4)	(1.3)
Deferred Regulatory and Other Charges	15.0	5.4	1.0
Other, net	3.9	(3.9)	(2.3)
Cash Provided by Operating Activities	96.3	66.7	45.9
Investing Activities:
Property, Plant and Equipment Additions	(89.5)	(68.5)	(57.1)
Cash (Used In) Investing Activities	(89.5)	(68.5)	(57.1)
Financing Activities:
Proceeds from (Repayment of) Short-Term Debt, net	10.8	(38.5)	21.1
Repayment of Long-Term Debt	(0.5)	(0.5)	(0.5)
Net Increase (Decrease) in Gas Inventory Financing	1.2	(3.8)	4.6
Dividends Paid	(19.1)	(17.2)	(15.2)
Retirement of Preferred Stock		(1.8)
Proceeds from Issuance of Common Stock	1.1	66.8	1.0
Other, net	(0.7)	(0.9)	(1.2)
Cash (Used In) Provided by Financing Activities	(7.2)	4.1	9.8
Net Increase (Decrease) in Cash	(0.4)	2.3	(1.4)
Cash at Beginning of Year	9.8	7.5	8.9
Cash at End of Year	9.4	9.8	7.5
Supplemental Information:
Interest Paid	20.8	21.2	21.2
Income Taxes Paid (Refunded)	0.8	0.7	(7.3)
Non-cash Investing Activity:
Capital Expenditures Included in Accounts Payable	$ 0.7	$ 1.9	$ 2.6