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Regulatory matters and revenues subject to refund (Details) (USD $) | 0 Months Ended
--- | ---
Jul. 10, 2014 NDPSC [Member] | Feb. 27, 2014 NDPSC [Member] | Aug. 11, 2014 MTPSC [Member] | Oct. 31, 2013 FERC [Member] | Oct. 03, 2014 Subsequent event [Member] WYPSC [Member]
Regulatory matters and revenues subject to refund [Line Items] |  |  |  |  |
Annual amount recovered | $ 8,600,000 |  |  |  |
Rate increase requested |  | 7,400,000 | 3,000,000 |  | 788,000
Percent above current rates requested |  | 4.60% | 3.60% |  | 4.10%
Interim rate increase (decrease), amount |  |  | 2,200,000 |  |
Interim rate increase, percent |  |  | 2.60% |  |
Increased expenditures covered by change application |  |  |  | 312,000,000 |
Approximate annual increase in revenues |  |  |  | $ 11,500,000 |

X
- Definition The amount of requested interim increase in annual gas rates. + References No definition available. + Details
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X
- Definition Approximate annual increase in revenues based on adjusted base period volumes. + References No definition available. + Details
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X
- Definition Increased investments covered by change application. + References No definition available. + Details
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X
- Definition The percentage of interim gas rate increase requested. + References No definition available. + Details
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X
- Definition Amount of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
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- 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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