Rate Matters (Details) (Public Service Commission of Wisconsin (PSCW) [Member], NSP-Wisconsin [Member], USD $) In Millions, unless otherwise specified	1 Months Ended
May 31, 2013
Electric and Gas Rate Case 2014, Electric Rates [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 40.0
Public Utilities, Requested Rate Increase (Decrease), Percentage	6.50%
Electric and Gas Rate Case 2014, Gas Rates [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	4.7
Public Utilities, Requested Rate Increase (Decrease), Percentage	3.80%
Electric and Gas Rate Case 2014 [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Return on Equity, Percentage	10.40%
Public Utilities, Requested Equity Capital Structure, Percentage	52.50%
Forecasted Average Net Investment Rate Base, Electric Utility	895.3
Forecasted Average Net Investment Rate Base, Natural Gas Utility	$ 89.8

- Definition

Amount of public utility's forecasted average net investment rate base in the filing with regulatory agency on which the public utility is allowed to earn a particular rate of return.

+ References

No definition available.

+ Details

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- Definition

Amount of public utility's forecasted average net investment rate base in the filing with regulatory agency on which the public utility is allowed to earn a particular rate of return.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's requested equity to capital, including debt and equity.

+ 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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- Definition

Percentage of public utility's requested return on equity.

+ References

No definition available.

+ Details

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