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Regulatory matters and revenues subject to refund (Details) (USD $) In Millions, unless otherwise specified | 0 Months Ended
--- | ---
Feb. 27, 2014 NDPSC [Member] | Nov. 17, 2013 NDPSC [Member] | Sep. 18, 2013 NDPSC [Member] | Oct. 31, 2013 FERC [Member]
Regulatory matters and revenues subject to refund [Line Items] |  |  |  |
Rate increase requested | $ 7.4 |  | $ 6.8 |
Percent above current rates requested | 4.60% |  | 6.40% |
Interim rate increase (decrease), amount |  | 4.3 |  |
Interim rate increase, percent |  | 4.00% |  |
Rate change application annual increase, amount |  |  |  | 28.9
Increased expenditures covered by change application |  |  |  | $ 312

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- Definition Increased investments covered by change application. + References No definition available. + Details
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- Definition Interim increase (decrease), percent. + References No definition available. + Details
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X
- Definition General natural gas rate change application increase, amount. + References No definition available. + Details
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- Details
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- Definition Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency. + References No definition available. + Details
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- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
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- Definition Percentage of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
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