The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

No definition available.

+ Details

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 405

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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Regulatory Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Regulatory Assets [Line Items]
Regulatory Assets	$ 165,183us-gaap_RegulatoryAssets	$ 113,543us-gaap_RegulatoryAssets
Regulatory Liabilities [Line Items]
Regulatory Liabilities	22,715us-gaap_RegulatoryLiabilities	33,330us-gaap_RegulatoryLiabilities
Debt make-whole premium	0	6,757	0
Conservation Costs Regulatory Liability [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	680	455
Deferred Fuel Savings [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	755	13,386
Elm Road Regulatory Liability [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	1,497	607
Income Taxes [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	1,794	2,082
Non-ARO Removal Cost [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	16,129	15,182
Renewable Energy Credits [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	753	574
Other Regulatory Liability [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities	1,107	1,044
Asset Retirement Obligation [Member]
Regulatory Assets [Line Items]
Regulatory Assets	4,532	4,863
Debt Related Costs [Member]
Regulatory Assets [Line Items]
Regulatory Assets	11,133	11,786
Derivatives [Member]
Regulatory Assets [Line Items]
Regulatory Assets	54,998	63,893
Environmental Costs [Member]
Regulatory Assets [Line Items]
Regulatory Assets	700	920
Tax Recovery AFUDC Equity [Member]
Regulatory Assets [Line Items]
Regulatory Assets	8,821	6,956
Unfunded Pension and Other Postretirement Plans Costs [Member]
Regulatory Assets [Line Items]
Regulatory Assets	84,551	24,591
Other Regulatory Asset [Member]
Regulatory Assets [Line Items]
Regulatory Assets	$ 448	$ 534