Estimated cost of remediating sites
Accrual for Environmental Loss Contingencies
Accumulated Other Comprehensive Income (Loss), Net of Tax
Accumulated other comprehensive loss
Less accumulated depreciation
Less accumulated depreciation
Additional Paid in Capital
Additional paid in capital
Utility capital/construction expenditures
Payments to Acquire Productive Assets
Amortization of investment tax credits
Investment Tax Credit
Dividends from unconsolidated subsidiaries
Equity Method Investment, Dividends or Distributions
Net realized and unrealized hedging and derivative transactions
Unrealized Gain (Loss) on Derivatives and Commodity Contracts
Less allowance for bad debts
Less allowance for bad debts
Allowance for Bad Debts [Member]
AFUDC Recorded In Plant [Member]
Conservation and demand side management program amortization
Amortization of Regulatory Asset
Amount of accumulated other comprehensive gains (losses) related to interest rate derivatives expected to be reclassified into earnings within the next twelve months
Amount of accumulated other comprehensive gains (losses) related to commodity derivatives expected to be reclassified into earnings within the next twelve months
Restricted Stock [Member]
Restricted Stock [Member]
Asset-Backed Securities [Member]
Asset-backed securities [Member]
Asset-Backed Securities [Member]
Recoverable Purchased Natural Gas and Electric Energy Costs [Member]
Beginning balance
Ending balance
Asset Retirement Obligation
Plant Removal Costs [Member]
Net AROs [Member]
Plant Removal Costs [Member]
Reconciliation of Beginning and Ending Aggregate Carrying Amounts of Asset Retirement Obligations
Accretion
Fair value of assets legally restricted for purposes of settling the nuclear ARO
Liabilities recognized
Liabilities settled
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligations
Asset Retirement Obligations, Noncurrent
Revisions to prior estimates
Current assets related to discontinued operations
Assets of Disposal Group, Including Discontinued Operation, Current
Noncurrent assets related to discontinued operations
Noncurrent assets related to discontinued operations
Condensed Balance Sheets [Abstract]
Earnings per share (in dollars per share)
Earnings per average common share - basic (in dollars per share)
Earnings per share total - basic (in dollars per share)
First Mortgage Bonds [Member]
Purchase price of the Rocky Mountain Energy Center and the Blue Spruce Energy Center generation assets
Acquisition cost of Rocky Mountain Energy Center and Blue Spruce Energy Center natural gas generation assets
Recoverable acquisition-related legal and consulting costs that are deferred as a regulatory asset
Acquisition of Generation Assets, Purchase Price Allocation [Abstract]
Total assets acquired
Net assets acquired
Inventory
Accrued expenses
Total liabilities assumed
Property, plant and equipment
Accumulated depreciation
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation
Total property held under capital leases, net
Total minimum obligation
Capital Leases, Future Minimum Payments Due [Abstract]
2011
Capital Leases, Future Minimum Payments Due, Current
2015
Capital Leases, Future Minimum Payments Due in Five Years
2014
Capital Leases, Future Minimum Payments Due in Four Years
2013
Capital Leases, Future Minimum Payments Due in Three Years
2012
Capital Leases, Future Minimum Payments Due in Two Years
Thereafter
Capital Leases, Future Minimum Payments Due Thereafter
Interest component of obligation
Present value of minimum obligation
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period
Cash and cash equivalents
Cash and Cash Equivalents
Cash Equivalents [Member]
Cash Equivalents [Member]
Cash paid for interest (net of amounts capitalized)
Interest Paid, Net
Recoverable purchased natural gas and electric energy costs
Increase (Decrease) in Deferred Fuel Costs
Pension and other employee benefit obligations
Increase (Decrease) in Employee Related Liabilities
Inventories
Increase (Decrease) in Inventories
Net regulatory assets and liabilities
Increase (Decrease) in Regulatory Assets and Liabilities
Proceeds from (repayment of) short-term borrowings, net
Proceeds from short-term borrowings, net
Accrued unbilled revenues
Increase (Decrease) in Unbilled Receivables
Increase (Decrease) in Operating Capital [Abstract]
Changes in operating assets and liabilities
Accounts payable
Increase (Decrease) in Accounts Payable
Commitments and Contingent Liabilities
Common stockholders' equity, authorized shares (in shares)
Common Stockholders' Equity Authorized
Common stock, shares authorized (in shares)
Common stock, shares, outstanding (in shares)
Common Stock, Value, Issued
Common stock - $2.50 par value per share
Components of Net Deferred Tax Liability from Continuing Operations [Abstract]
Components of Income Tax Expense from Continuing Operations [Abstract]
Comprehensive income for the period
Comprehensive Income, Net of Tax, Attributable to Parent
Schedule 1 Condensed Financial Statements of Xcel Energy, Inc.
Construction work in progress
Construction in Progress, Gross
Electric fuel and purchased power
Cost of Domestic Regulated Electric
Cost of sales - other
Other Cost of Operating Revenue
Cost of natural gas sold and transported
Cost of Purchased Oil and Gas
Amount paid under technology agreement
Asset-backed Securities [Member]
Asset-backed Securities, Securitized Loans and Receivables [Member]
Current federal tax expense (benefit)
Total current liabilities
Total current liabilities
Current liabilities
Liabilities, Current [Abstract]
Current portion of long-term debt
Current portion of long-term debt
Current state tax expense
Customer advances
Customer Advances for Construction
Long-term debt
Long-term debt
Borrowings and other financing instruments
Long-term Debt, Gross
Debt instrument, face amount
Debt instrument, interest rate, stated percentage (in hundredths)
Debt instrument, interest rate, stated percentage (in hundredths)
Debt instrument, issuance date
Debt instrument, issuer
Debt instrument, issuer
Debt instrument, maturity date
Debt instrument, maturity date
Debt Instrument, Name [Domain]
Debt Instrument, Unamortized Discount
Debt Instrument [Axis]
Debt instrument [Line Items]
Long-term borrowings and other financing instruments [Table]
Interest charges - includes other financing costs
Debt Related Commitment Fees and Debt Issuance Costs
Discounted decommissioning cost obligation
Assets held in external decommissioning trust
Fair value
Deferred federal tax expense
Unrecovered Natural Gas Costs [Member]
Deferred income taxes
Deferred Income Tax Expense (Benefit)
Deferred Tax Assets, Net, Current
Deferred income taxes
Deferred state tax expense
Total deferred tax assets
Total deferred tax assets
Net deferred tax liability
Net deferred tax liability
NOL carryforward
Deferred Tax Assets Operating Loss Carryforwards
Tax credit carryforward
Accrued liabilities and other
Bad debts
Total deferred tax liabilities
Total deferred tax liabilities
Other
Deferred Tax Liabilities, Other
Regulatory assets
Deferred Tax Liabilities, Regulatory Assets
Deferred income taxes
Deferred Tax Liabilities, Noncurrent
Deferred Income Tax Adjustment [Member]
Defined Benefit Plans [Domain]
Defined Contribution Plans [Abstract]
Contributions to 401(k) and other defined contribution plans
Depreciation and amortization
Depreciation and amortization
Depreciation, Amortization and Accretion, Net
Derivative instruments
Current derivative instruments valuation
Derivative Assets, Current
Derivative instruments
Noncurrent derivative instruments valuation
Derivative Assets, Noncurrent
Derivative, by Nature [Axis]
Derivatives [Member]
Derivative instruments
Current derivative instruments valuation
Derivative Liabilities, Current
Derivative instruments
Noncurrent derivative instruments valuation
Derivative Liabilities, Noncurrent
Derivatives [Line Items]
Derivative [Table]
Types of and Accounting for Derivative instruments
Current exposure
Guarantee amount
Guarantor Obligations, Nature [Domain]
Triggering event
Guarantor Obligations by Nature [Axis]
Guarantor Obligations [Line Items]
Schedule of Guarantor Obligations [Table]
Earnings per share (in dollars per share)
Earnings per average common share - diluted (in dollars per share)
Earnings per share total - diluted (in dollars per share)
Expected Medicare Part D subsidies [Abstract]
Equity earnings of unconsolidated subsidiaries
Equity earnings of unconsolidated subsidiaries
Equity earnings of subsidiaries
Effective income tax rate from continuing operations (in hundredths)
Effective income tax rate from continuing operations (in hundredths)
Effective Tax Rate Reconciliation [Abstract]
Federal statutory rate (in hundredths)
Life insurance policies (in hundredths)
Other, net (in hundredths)
State income taxes, net of federal income tax benefit (in hundredths)
Total compensation cost capitalized
Compensation cost for share-based awards
Allocated Share-based Compensation Expense
Compensation costs related to share-based awards [Abstract]
Tax benefit recognized in income
Share-based compensation expense
Share-based Compensation
Estimated cost of remediating sites, current liability
Environmental Remediation Costs [Member]
Ownership interest in WYCO (in hundredths)
Equity Securities - Common Stock [Member]
Extinguishment of debt amount
Amount received as full and final settlement with Provident and Reassure America Life Insurance Company
Statements of Income [Abstract]
Income from continuing operations (in dollars per share)
Income (Loss) from Continuing Operations, Per Diluted Share
Income from continuing operations (in dollars per share)
Income (Loss) from Continuing Operations, Per Basic Share
Income (loss) from discontinued operations, net of tax
Remove (income) loss from discontinued operations
Discontinued operations - income (loss)
Income (loss) from discontinued operations, net of tax
Income (loss) from discontinued operations (in dollars per share)
Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share
Income (loss) from discontinued operations (in dollars per share)
Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share
Income Tax Examination [Line Items]
Income Tax Examination [Table]
Income Taxes
Income Tax
Cash (paid) received for income taxes, net.
Income Taxes Paid, Net
Change in restricted cash
Increase (Decrease) in Restricted Cash
401(k) equity awards (in shares)
Convertible senior notes (in shares)
Stock options (in shares)
Interest charges - includes other financing costs of $20,638, $20,162, and $20,390, respectively
Interest Expense
Interest Income [Member]
Inventories
Inventories, net
Inventories [Abstract]
Inventories
Inventory, Policy [Text Block]
Purchase of investments in external decommissioning fund
Payments to Invest in Decommissioning Fund
Ownership % (in hundredths)
Construction work in progress
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress
Jointly Owned Utility Plant [Axis]
Jointly Owned Utility Plant [Domain]
Plant in service
Jointly Owned Utility Plant Interests [Table]
Accumulated depreciation
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation
Total rental expense under operating lease obligations
Summary of Property Held Under Capital Leases
Current liabilities related to discontinued operations
Liabilities of Disposal Group, Including Discontinued Operation, Current
Noncurrent liabilities related to discontinued operations
Liabilities of Disposal Group, Including Discontinued Operation, Noncurrent
Total liabilities and equity
Total liabilities and equity
Liabilities and Stockholders' Equity [Abstract]
Liabilities and Equity
Drawn
Facility
Available
Line of Credit Facility [Line Items]
Credit Facilities
Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain]
Less current maturities
Long-term Debt, Current Maturities
2011
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months
2015
Long-term Debt, Maturities, Repayments of Principal in Year Five
2014
Long-term Debt, Maturities, Repayments of Principal in Year Four
2013
Long-term Debt, Maturities, Repayments of Principal in Year Three
2012
Long-term Debt, Maturities, Repayments of Principal in Year Two
Long-term Debt, excluding current maturities
Long-term Debt, Excluding Current Maturities
Long-term Debt, including current maturities
Number of settlements with insurers
Maximum public liability coverage required for claims resulting from any nuclear incident
Indemnification limit on damages
Losses on Reacquired Debt [Member]
Short-Term Investments and Money Market Securities [Member]
Mortality table
Mortgage-Backed Securities [Member]
Mortgage-backed securities [Member]
Mortgage-backed Securities [Member]
Net increase (decrease) in cash and cash equivalents - discontinued operations
Net Cash Provided by (Used in) Discontinued Operations
Net cash provided by (used in) financing activities
Net cash used in (provided by) financing activities
Net Cash Provided by (Used in) Financing Activities [Abstract]
Financing activities
Net cash used in investing activities
Net cash used in investing activities
Net Cash Provided by (Used in) Investing Activities [Abstract]
Investing activities
Net cash provided by operating activities
Net cash provided by operating activities
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net Cash Provided by (Used in) Operating Activities
Earnings available to common shareholders
Earnings available to common shareholders
Net increase (decrease) in cash and cash equivalents
Net increase (decrease) in cash and cash equivalents
Accounting Pronouncements
Total interest charges and financing costs
Interest charges and financing costs
Interest and Debt Expense [Abstract]
Interest charges and financing costs
Total other assets
Assets, Noncurrent [Abstract]
Other assets
Total other liabilities
Liabilities, Noncurrent [Abstract]
Deferred credits and other liabilities
Notes Payable, Other Payables [Member]
Nuclear Fuel [Member]
Nuclear Fuel Storage [Member]
Total Operating Leases, Future Minimum Payments Due [Abstract]
2011
Operating Leases, Future Minimum Payments Due, Current
2015
Operating Leases, Future Minimum Payments, Due in Five Years
2014
Operating Leases, Future Minimum Payments, Due in Four Years
2013
Operating Leases, Future Minimum Payments, Due in Three Years
2012
Operating Leases, Future Minimum Payments, Due in Two Years
Thereafter
Operating Leases, Future Minimum Payments, Due Thereafter
NOL carryforward
Valuation allowances for state NOL carryforwards
Operating income
Operating income
Total operating revenues
Total revenues
Operating revenues
Revenues [Abstract]
Revenues
Changes in unrecognized amounts of pension and retiree medical benefits, net of tax
Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax
Net derivative instrument fair value changes, net of tax
Other Comprehensive Income, Derivatives Qualifying as Hedges, Net of Tax
After-tax net realized losses on derivative transactions reclassified into earnings
After-tax net unrealized gains (losses) related to derivatives accounted for as hedges
Unrealized gain (loss) - marketable securities, net of tax
Other Comprehensive Income, Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax
Unrealized gain (loss) - marketable securities, tax
Other Comprehensive Income, Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax
Other current assets
Other Assets, Current
Miscellaneous investments
Other income (expense), net
Other income, net
Other income
Total contributions to Xcel Energy's postretirement health care plans during the year
Dividends paid
Dividends paid
Total contributions to Xcel Energy's pension plans during the year
Pension Contributions
Benefit Plans and Other Postretirement Benefits
Accumulated benefit obligation at Dec. 31
Actual return (loss) on plan assets
Actuarial loss (gain)
2016-2020
Defined Benefit Plan, Expected Future Benefit Payments in Five Fiscal Years Thereafter
Amortization of net loss
Amortization of net loss
Amortization of prior service cost
Amortization of transition obligation
Net postretirement amounts recognized on consolidated balance sheet
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Benefit payments
Change in Projected Benefit Obligation [Roll Forward]
Change in Fair Value of Plan Assets [Roll Forward]
Components of Net Periodic Benefit Cost [Abstract]
Employer contributions
Plan participants' contributions
Current liabilities
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities
Discount rate for year-end valuation
Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
1-percent decrease in APBO components as of end of period
1-percent decrease in service and interest components of the net periodic cost
1-percent increase in APBO components as of end of period
1-percent increase in service and interest components of the net periodic cost
Projected pension benefit payments [Abstract]
2011
Defined Benefit Plan, Expected Future Benefit Payments in Year One
2012
Defined Benefit Plan, Expected Future Benefit Payments in Year Two
2013
Defined Benefit Plan, Expected Future Benefit Payments in Year Three
2014
Defined Benefit Plan, Expected Future Benefit Payments in Year Four
2015
Defined Benefit Plan, Expected Future Benefit Payments in Year Five
Expected return on plan assets
Expected return on plan assets
Defined benefit plan, fair value of plan assets
Fair value of plan assets at Jan. 1
Fair value of plan assets at Dec. 31
Defined Benefit Plan, Fair Value of Plan Assets
Funded status
Interest cost
Basis used to determine overall expected return on asset portfolio
Total
Defined Benefit Plan, before Adoption of FAS 158 Recognition Provisions, Net Amount Recognized
Plan amendments
Expected average long-term increase in compensation level
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase
Service cost
Target Pension Asset Allocations [Abstract]
Net loss
Prior service cost (credit)
Prior service cost (credit)
Transition obligation
Transition obligation
Significant assumptions used to measure benefit obligation [Abstract]
Significant Assumptions Used to Measure Costs [Abstract]
Defined Benefit Plans Disclosures, Defined Benefit Plans [Axis]
Obligation at Jan. 1
Obligation at Dec. 31
Defined Benefit Plan, Benefit Obligation
Defined Benefit Plan Disclosure [Line Items]
Schedule of Defined Benefit Plans Disclosures [Table]
Preferred stockholders' equity, authorized shares (in shares)
Preferred Stock, Shares Authorized
Preferred stock, shares authorized (in shares)
Preferred stockholders' equity, outstanding shares (in shares)
Preferred stock, shares outstanding (in shares)
Preferred stock, shares outstanding (in shares)
Dividend requirements on preferred stock
Dividend requirements on preferred stock
Less: Dividend requirements on preferred stock
Dividend requirements on preferred stock
Preferred stockholders' equity, par value (in dollars per share)
Preferred stock, par value (in dollars per share)
Preferred stock, par value (in dollars per share)
2016-2020
Prescription Drug Subsidy Receipts, Five Fiscal Years Thereafter
Medicare subsidy reimbursements
2011
Prescription Drug Subsidy Receipts, Year One
2012
Prescription Drug Subsidy Receipts, Year Two
2013
Prescription Drug Subsidy Receipts, Year Three
2014
Prescription Drug Subsidy Receipts, Year Four
2015
Prescription Drug Subsidy Receipts, Year Five
Proceeds from issuance of common stock
Proceeds from issuance of common stock
Draw on Shaw's letter of credit
Proceeds from issuance of long-term debt
Proceeds from issuance of long-term debt
Proceeds from the sale of investments in external decommissioning fund
Proceeds from Decommissioning Fund
Proceeds from Sale of Property, Plant, and Equipment
Proceeds from the sale of assets
Total property, plant and equipment
Property, plant and equipment, net
Property, plant and equipment, net
Property, Plant and Equipment, Net
Property, Plant and Equipment and Depreciation
Provision for bad debts
Provision for Doubtful Accounts
Tax expense resulting from net non-recurring adjustment
Allowance for funds used during construction - debt
Public Utilities, Allowance for Funds Used During Construction, Capitalized Interest
Operating life of Monticello nuclear plant
Investment in WYCO Development LLC
Payments to Acquire Equity Method Investments
Acquisition of generation assets
Payments to Acquire Property, Plant, and Equipment
Other investments
Payments for (Proceeds from) Investments
Accounts receivable, net
Accounts receivable from subsidiaries
Accounts Receivable and Allowance for Bad Debts
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Regulatory Asset [Axis]
Regulatory Asset [Domain]
Regulatory assets, current
Regulatory assets
Regulatory assets
Regulatory assets, noncurrent
Regulatory liabilities
Regulatory liabilities, current
Regulatory Liability [Axis]
Regulatory Liability [Domain]
Regulatory liabilities
Regulatory liability, noncurrent
Regulatory liabilities, noncurrent
Repayment of long-term debt, including reacquisition premiums
Repayment of long-term debt
Reporting Segment [Domain]
Retained Earnings (Accumulated Deficit)
Retained earnings
Adoption of new accounting guidance for endorsement split-dollar life insurance, net of tax
Cumulative Effect of Initial Adoption of New Accounting Principle
Electric
Electric Domestic Regulated Revenue
Revenue Recognition
Other
Other Sales Revenue, Net
Guarantees Issued and Outstanding
Generating Plant Ownership and Operation
Acquisition of Generation Assets
Compensation costs related to share-based awards
Committed Credit Facilities Available
Activity in Stock Options
Schedule II Valuation and Qualifying Accounts
Securities Lending Collateral Obligation and Other [Member]
Segments and Related Information
Schedule of Continuing Operating Revenues and Income of Reportable Segments
Intersegment revenues
Equity investments in unconsolidated subsidiaries
Operating revenues from external customers
Segment Reporting Information, by Segment [Axis]
Segment Reporting Information [Line Items]
Schedule of Segment Reporting Information, by Segment [Table]
Senior Notes [Member]
Preferred Stock $4.08 Series [Member]
Preferred Stock $4.10 Series [Member]
Preferred Stock $4.11 Series [Member]
Preferred Stock $4.16 Series [Member]
Preferred Stock $4.56 Series [Member]
Preferred Stock $3.60 Series [Member]
Forfeited (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period
Forfeited (in shares)
Forfeited, weighted average grant date fair value (in dollars per share)
Granted (in shares)
Balance at January 1 (in shares)
Balance at December 31 (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number
Balance at January 1, weighted average grant date fair value (in dollars per share)
Granted, weighted average grant date fair value (in dollars per share)
Balance at December 31, weighted average grant date fair value (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Unrecognized compensation cost related to nonvested share-based compensation awards
Weighted-average period for recognition of unrecognized compensation cost related to nonvested share-based compensation awards (in years)
Vested (in shares)
Vested (in shares)
Total fair value of RSUs vested during the period
Vested, weighted average grant date fair value (in dollars per share)
Vesting period for stock options after grant date
Award vesting period (in years)
Number outstanding and exercisable (in shares)
Weighted average remaining contractual life (in years)
Weighted average exercise price (in dollars per share)
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain]
Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Axis]
Exercise price range of options, upper range limit (in dollars per share)
Exercise Price Range [Line Items]
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table]
Exercised (in shares)
Exercised (in shares)
Intrinsic value of options exercised
Exercised, average exercise price (in dollars per share)
Expired (in shares)
Expired (in shares)
Expired, average exercise price (in dollars per share)
Forfeited (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period
Forfeited (in shares)
Forfeited, average exercise price (in dollars per share)
Outstanding at beginning of year (in shares)
Outstanding at end of year (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number
Outstanding at beginning of year, average exercise price (in dollars per share)
Outstanding at end of year, average exercise price (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Exercisable at end of year (in shares)
Exercisable at end of year, average exercise price (in dollars per share)
Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Award Type and Plan Name [Axis]
Cash received from stock options exercised
Share-based Compensation Arrangements by Share-based Payment Award, Award Type and Plan Name [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding and Exercisable by Exercise Price
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Weighted average interest rate (in hundredths)
Short-term debt
Commercial paper outstanding
Short-term debt
Short-Term Investments [Member]
Summary of Significant Accounting Policies
State Jurisdiction [Member]
Statements of Cash Flows [Abstract]
Statement of Stockholders' Equity [Abstract]
Preferred and Common Stock
Summary of Income Tax Contingencies
Earliest Open Tax Years Subject to Examination by State Taxing Authorities in the Major Operating Jurisdictions
Supplemental Cash Flow Information [Abstract]
Federal tax credit carryforwards
Total current assets
Total current assets
Current assets
Assets, Current [Abstract]
Government Securities [Member]
US Treasury and Government [Member]
Estimated Future Payments For Capacity that the Utility Subsidiaries are Obligated to Purchase, Subject to Availability
United States Pension Plans of US Entity, Defined Benefit [Member]
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member]
Unrecognized tax benefit balance
Balance at Jan. 1
Balance at Dec. 31
Unrecognized tax benefit balance
Reductions based on tax positions related to the current year - continuing operations
Lapse of applicable statutes of limitations - continuing operations
Settlements with taxing authorities - continuing operations
Additions based on tax positions related to the current year - continuing operations
Additions for tax positions of prior years - continuing operations
Unrecognized tax benefit - Permanent tax positions
Unrecorded Unconditional Purchase Obligation [Table]
Unsecured Debt [Member]
Purchase power agreement payments included in total rental expense
Balance at Jan. 1
Balance at Dec. 31
Valuation Allowances and Reserves, Balance
Charged to costs and expenses
Charged to other accounts
Deductions from reserves
Valuation Allowances and Reserves [Domain]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves Type [Axis]
Valuation and Qualifying Accounts Disclosure [Table]
Amounts Reflected in Consolidated Balance Sheets for the Eloigne and NSP-Wisconsin Low-income Housing Limited Partnerships
Diluted (in shares)
Weighted average common shares outstanding - diluted (in shares)
Basic (in shares)
Weighted average common shares outstanding - basic (in shares)
Subsidiaries [Member]
Common Stock [Member]
Property, plant and equipment, net [Abstract]
Nuclear Decommissioning Fund Assets
Schedule of Nuclear Decommissioning Fund Assets [Table]
Major Types of Assets [Domain]
U.S. Corporate Bonds [Member]
Preferred Stock [Member]
Total debt securities
Due in 1 year of less
Due in 1 to 5 years
Due in 5 to 10 years
Due after 10 years
Final Contractual Maturity Dates of Debt Securities in the Nuclear Decommissioning Fund [Abstract]
Decommissioning Fund Assets [Abstract]
Total assets
Total assets
Assets
Accounts receivable, net [Abstract]
Deferred financing costs, net of amortization included in other assets
Other
Other current liabilities
Other Liabilities, Current
Other
Other liabilities
Income Tax Examination by Jurisdiction [Axis]
Income Tax Authority [Domain]
Cash dividends declared per common share (in dollars per share)
Dividends declared per common share
Share-Based Compensation
Fair Value, by Balance Sheet Grouping [Table]
Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis]
Fair Value, Disclosure Item Amounts [Domain]
Carrying Amount [Member]
Fair Value [Member]
Fair Value of Financial Instruments [Line Items}
Statement [Table]
Allowance for Bad Debts: [Rollforward]
Assets [Abstract]
Assets
Assets [Abstract]
Statement [Line Items]
Amount Not Yet Recognized As Component Of Net Periodic Benefit Cost [Abstract]
Funded Status of Plans at Dec. 31 [Abstract]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Cash equivalents
Fair Value, Assets Measured on Recurring Basis, Cash and Cash Equivalents
Balance at Jan. 1
Balance at Dec. 31
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value
Purchases, issuances and settlements, net
Transfers that occurred between Level 2 and Level 3, assets
Changes in Level 3 Plan Assets [Roll Forward]
Transfers that occurred between Level 2 and Level 3, liabilities
Discount rate
Expected average long-term increase in compensation level
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase
Operating Loss and Tax Credit Carryforwards [Line Items]
Operating Loss Carryforwards [Line Items]
Fair Value, Inputs, Level 1 [Member]
Level 1 [Member]
Fair Value, Inputs, Level 2 [Member]
Level 2 [Member]
Fair Value, Inputs, Level 3 [Member]
Level 3 [Member]
Storage assets under capital lease
Capital Lease Obligations Incurred
Financial Instruments
Financial Instruments, Estimated Fair Values
Summary of Property Held Under Capital Leases [Abstract]
Property held under capital lease
Summarized Quarterly Financial Data (Unaudited)
Quarterly Financial Information [Text Block]
Operating cash flows provided by (used in) discontinued operations
Cash Provided by (Used in) Operating Activities, Discontinued Operations
Class of Stock [Domain]
Acquisition of Generation Assets, Purchase Price [Abstract]
Selected Quarterly Financial Information [Abstract]
Balance of accumulated other comprehensive loss related to cash flow hedges at beginning of period
Balance of accumulated other comprehensive loss related to cash flow hedges at end of period
Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax
Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis]
Unrecorded Unconditional Purchase Obligation [Line Items]
Committed Minimum Payments Under Technology Agreements
Internal Revenue Service (IRS) [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Increase (decrease) in Stockholders' Equity
Tax benefit realized for the tax deductions from stock options exercised
Other operating and maintenance expenses
Other Cost and Expense, Operating
Other
Other assets
Operating expenses
Earnings Per Share, Basic [Abstract]
Basic earnings per share:
Earnings per average common share - basic:
Earnings Per Share, Diluted [Abstract]
Diluted earnings per share:
Earnings per average common share - diluted:
Antidilutive weighted-average options outstanding excluded from earnings per share calculation
Dilutive Impact of Common Stock Equivalents on Earnings per Share
Schedule of Nuclear Decommissioning Fund, Major Types of Assets [Axis]
Schedule of Nuclear Decommissioning Fund Assets [Line Items]
Parent Company [Member]
Xcel Energy Inc. [Member]
Parent Company [Member]
Class of Stock [Axis]
Gain on sale of assets which will be shared
Capital lease obligation for Totem natural gas storage arrangement
Common stockholders' equity, par value (in dollars per share)
Common stock, par value (in dollars per share)
Common Stock, Par or Stated Value Per Share
Measurement Date
Net derivative instrument fair value changes, tax
Other Comprehensive Income, Derivatives Qualifying as Hedges, Tax Effect
Changes in unrecognized amounts of pension and retiree medical benefits, tax
Other Comprehensive Income, Defined Benefit Plans, Tax
Deferred Financing Costs
Deferred Tax Assets [Abstract]
Deferred Tax Liabilities [Abstract]
Differences between book and tax bases of property
Income taxes
Total income tax expense from continuing operations
Income tax expense (benefit)
Pension and Other Postretirement Benefit Contributions [Abstract]
Allowance for funds used during construction - equity
Allowance for equity funds used during construction
Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity
Jointly Owned Utility Plant Interests [Line Items]
Preferred stockholders' equity - authorized 7,000,000 shares of $100 par value; outstanding shares: 1,049,800
Preferred Stock, Value, Issued
Preferred stockholders' equity
Common Stock and Equivalents [Abstract]
Preferred Stock [Abstract}
Government Securities [Member]
US Government Agencies Debt Securities [Member]
Common and other property
Accounts receivable
Increase (Decrease) in Accounts and Other Receivables
Statement, Equity Components [Axis]
Additional Paid-in Capital [Member]
Retained Earnings [Member]
Accumulated Other Comprehensive Income [Member]
Equity Component [Domain]
Exercise price range of options, lower range limit (in dollars per share)
Property, plant and equipment additions in accounts payable
Capital Expenditures Incurred but Not yet Paid
Amount received as full and final settlement
Legal Costs
Issuances of common stock
Stock Issued During Period, Value, New Issues
Issuances of common stock (in shares)
Total number of shares of common stock issued to underwriters (in shares)
Materials and supplies
Deferred investment tax credits
Accumulated Deferred Investment Tax Credit
Reconciling Eliminations [Member]
Schedule of Condensed Financial Statements [Table]
Condensed Financial Statements of Xcel Energy, Inc.
Condensed Financial Statements, Captions [Line Items]
Natural gas
Gas Domestic Regulated Revenue
Earnings available to common shareholders and assumed conversions
Effect of dilutive securities:
Costs and Expenses [Abstract]
Operating expenses
Total operating expenses
Costs and Expenses
Allowance for equity funds used during construction
Allowance for Funds Used During Construction, Investing Activities
Minimum fuel purchase commitment
Stock Options Activity [Rollforward]
Stock Options Average Exercise Price by Activity [Abstract]
Total Market Value and Total Intrinsic Value of Stock Options Exercised [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Common stock
Dividends, Common Stock
Common stockholders' equity, outstanding shares (in shares)
Balance (in shares)
Shares, Issued
Balance (in shares)
Net income
Net income
Net income
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Weighted average common shares outstanding:
Taxes (other than income taxes)
Taxes, Miscellaneous
Income from continuing operations
Income (loss) from continuing operations
Income from continuing operations
Hedging Relationship [Domain]
Class of stock [Line Items]
Schedule of Stock by Class [Table]
Leases [Abstract]
Commitments and contingent liabilities
Commitments and contingent liabilities
Restricted cash balance
Dividends [Abstract]
Dividends declared:
Schedule of Regulatory Assets [Table]
Regulatory Assets [Line Items]
Schedule of Plant Removal Costs [Table]
Schedule of Regulatory Liabilities [Table]
Schedule of Plant Removal Costs [Line Items]
Regulatory Liabilities [Line Items]
Adjustments to reconcile net income to cash provided by operating activities:
Operating activities
Plant Removal Costs by Entity
Domestic and international equity securities (in hundredths)
Capitalization, Long-term Debt and Equity [Abstract]
Capitalization
Total capitalization
Long-term Debt, Type [Axis]
Accounts payable
Accounts Payable, Current
Dividends payable
Dividends payable
Accrued interest
Interest Payable, Current
Taxes accrued
Taxes Payable, Current
Schedule of Capitalization, Long-term Debt [Table]
Schedule of Capitalization, Long-term Debt [Line Items]
Schedule of Capitalization, Equity [Table]
Schedule of Capitalization, Equity [Line Items]
Long-term Debt, Type [Domain]
Long-term Debt, Type [Domain]
Defined Benefit Plan by Plan Asset Categories [Axis]
Plan Asset Categories [Domain]
Real Estate [Member]
Real estate [Member]
Defined Benefit Plan, Fair Value of Plan Assets by Measurement [Axis]
Fair Value Plan Asset Measurement [Domain]
Alternative investments (in hundredths)
Noncurrent assets
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent
Pension and employee benefit obligations
Noncurrent liabilities
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent
Share-based compensation
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition, Value
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum
Long-term Debt, Net, Alternative [Abstract]
Long-term Debt, Net
Corporate Bonds [Member]
Municipal Bonds [Member]
Municipal Bonds [Member]
Private Equity Investments [Member]
Private equity investments [Member]
Debt Instrument, Maturity Date Range, Start
Debt Instrument, Maturity Date Range, End
Interest Rate [Member]
Trading Commodity [Member]
Other [Member]
Other Contract [Member]
Other Nonoperating Income [Member]
Other Nonoperating Expenses [Member]
Cash Flow Hedges [Member]
Derivatives Designated as Cash Flow Hedges [Member]
Other Derivative Instruments [Member]
Commodity Derivatives, Net [Member]
Credit Related Contingent Features [Abstract]
Derivative instruments in a net liability position
Payments required if credit ratings were downgraded below investment grade
Impact of Derivative Activity on OCI, Regulatory Assets and Liabilities, and Income
Derivative Instruments Gain (Loss) [Line Items]
Derivative Instruments Gain (Loss) by Hedging Relationship [Axis]
Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table]
Derivative Contract Type [Domain]
Amendment Flag
Current Fiscal Year End Date
Document Period End Date
Entity [Text Block]
Xcel Energy
Entity [Domain]
Entity Well-known Seasoned Issuer
Entity Voluntary Filers
Entity Current Reporting Status
Entity Filer Category
Entity Public Float
Entity Registrant Name
Entity Central Index Key
Entity Common Stock, Shares Outstanding
Document Fiscal Year Focus
Document Fiscal Period Focus
Legal Entity [Axis]
Document Type
Notional amount
Notional value of interest rate swap settled
Reserve Deducted From Related Assets Abstract
Reserve Deducted From Related Assets: [Abstract]
Valuation And Qualifying Accounts Disclosure Text Block
Disclosure of allowance and reserve accounts, including their beginning and ending balances, as well as a reconciliation by type of activity during the period.
Valuation and Qualifying Accounts
Investment In Subsidiaries
Investments in all wholly-owned subsidiaries.
Investment in subsidiaries
Capital Contributions To Subsidiaries
The cash outflow associated with the capital contributions to subsidiaries during the period.
Capital contributions to subsidiaries
Return Of Capital From Subsidiaries
The cash inflow associated with the excess distributions over earnings (i.e., return of capital) from subsidiaries during the period.
Return of capital from subsidiaries
Expenses And Other Deductions Abstract
Expenses and other deductions
Income Abstract
Income
Number Of Customers As Percentage Of Total Customers In Service Area
Number of customer served by SPS within Lubbock as a percentage of the total customers in the dually certified service area.
Number of customers as a percentage of total customers in the dually certified service area (in hundredths)
Number Of Days To Review And Approve Working Capital Adjustment
Number of days allowed in the purchase agreement for PSCo to review and approve the working capital adjustment based on an examination of the plants' books and records.
Number of days to review and approve the working capital adjustment
Liabilities Assumed Abstract
Liabilities Assumed [Abstract]
Assets Acquired Abstract
Assets Acquired [Abstract]
Business Acquisition Accrued Operating Liabilities
The decrease to the working capital adjustment for accrued operating liabilities of the acquired plants.
Accrued operating liabilities of the acquired plants
Business Acquisition Working Capital Adjustment
The working capital adjustments consisted of the settlement of PSCo's most recent purchases of energy and capacity under the terminated purchased power agreements.
Working capital adjustment for acquisition cost of Rocky Mountain Energy Center and Blue Spruce Energy Center natural gas generation assets
Asset Acquistion And Sale Text Block
Description of a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. Also a description and amounts of long lived assets held for sale.
Asset Acquisition and Sale
Summarized Quarterly Data Text Block
A schedule of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data.
Summarized Quarterly Financial Data (Unaudited)
All Other Member
Operating segments that do not meet the quantitative thresholds and thus are not classified as reportable segments for which there is an accounting requirement to report separate financial information on those components in the entity's financial statements.
All Other [Member]
Regulated Natural Gas Member
The operations of the regulated natural gas utility segment consists of the transporting, storing, and distributing natural gas in certain markets serviced by the entity.
Regulated Natural Gas [Member]
Regulated Electric Member
The core operations of the regulated electric utility segment consists of the generation, transmission, and distribution of electricity. In addition, this segment includes sales for resale and provides wholesale transmission service to other entities.
Regulated Electric [Member]
Regulatory Assets Related To Nonqualified Pension Plan
The current amount of regulatory assets associated with a non-qualified pension plan.
Regulatory assets related to non-qualified pension plan
Regulatory Recognition Of Pension Expense And Unamortized Prior Service Costs
Regulatory recognition of pension expense and unamortized prior service cost.
Regulatory recognition of NSP-Minnesota pension expense and PSCo unamortized prior service costs
Other Regulatory Liabilities Member
Other costs, which would otherwise be reflected as income, that are deferred as regulatory liabilities based on the expectation they will be refunded to customers through the ratemaking process.
Other Regulatory Liabilities [Member]
Interest On Income Tax Refunds Member
Interest received on income tax refunds deferred as a regulatory liability based on the expectation they will be refunded to customers through the ratemaking process.
Interest On Income Tax Refunds [Member]
Postretirement Medical Member
The unfunded portion of the postretirement medical obligation.
Postretirement Medical [Member]
Gain On Sale Of Emission Allowances Member
Gains on sales of emission allowances that are deferred as a regulatory liabilities based on the expectation they will be refunded to customers through the ratemaking process.
Gain on Sale of Emission Allowances [Member]
Wisconsin Overrecovered Fuel Costs Member
The excess of fuel revenues billed to customers in Wisconsin over fuel costs incurred. This over-recovered amount is deferred as a regulatory liability.
Wisconsin Overrecovered Fuel Costs [Member]
Decommissioning Fund Surplus Member
Surplus assets in the nuclear decommissioning escrow fund over the expected costs of decommissioning that was withdrawn from and subject to customer refund authorization by public utility commissions.
Decommissioning Fund Surplus [Member]
Low Income Discount Program Member
Costs associated with discount programs deferred as regulatory liabilities based on the expectation they will be refunded to customers through the ratemaking process.
Low Income Discount Program [Member]
Renewable Environmental Initiative Member
Costs incurred in government mandated environmental and renewable energy initiatives that were less than recoveries for those costs in the ratemaking process.
Renewable Environmental Initiative [Member]
Renewable Energy Credit Margin Sharing Member
Approved margin sharing agreement associated with certain sales of renewable energy credits designated as carbon offsets. These costs are recorded as a regulatory liability.
REC Margin Sharing [Member]
Proceeds From Asset Sales Member
Gain from the sale of assets which are expected to be refundable to customers through the ratemaking process.
Gain From Asset Sales [Member]
Investment Tax Credit Deferrals Member
Investment tax credits which are deferred as regulatory liabilities and are expected to be recovered from customers through the ratemaking process.
Investment Tax Credit Deferrals [Member]
Deferred Electric Gas And Steam Energy Cost Member
Carrying amount as of the balance sheet date of capitalized electric costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer.
Deferred Electric, Gas, and Steam Production Costs [Member]
Regulatory Asset Amortization Period
The amortization period for recovery of the individual regulatory asset in a schedule of regulatory assets.
Regulatory asset, remaining amortization period
Other Regulatory Assets Member
Other costs, which would otherwise be charged to expense, that are deferred as regulatory assets based on the expected ability to recover them in future rates.
Other Regulatory Assets [Member]
Miso Day2 Costs Member
Costs incurred by companies who are participants of the two-settlement energy market known as the day-2 market. These costs are deferred as regulatory assets based on the expected ability to recover them in future rates.
MISO Day 2 Costs [Member]
Rate Case Costs Member
Costs associated with filing various rate cases, which are deferred as regulatory assets based on the expected ability to recover them in future rates.
Rate Case Costs [Member]
State Commission Adjustments Member
State commission adjustments, which would otherwise be charged to expense, deferred as regulatory assets based on the expected ability to recover the expense in future rates.
State Commission Adjustments [Member]
Depreciation Differences Member
Differences in allowable depreciation methods or useful lives between different jurisdictions that give rise to a regulatory asset for costs that normally would be expensed.
Depreciation Differences [Member]
Gas Pipeline Inspection Costs Member
Gas pipeline inspection costs incurred that would otherwise be charged to expense. These costs are included in allowable costs for rate making purposes and future revenue will be provided to permit recovery of such incurred costs.
Gas Pipeline Inspection Costs [Member]
Nuclear Outage Costs Member
Costs associated with refueling outages as incurred at its nuclear plants that are deferred as regulatory assets based on the expected ability to recover them in future rates.
Nuclear Outage Costs [Member]
Purchased Power Contracts Costs Member
The amounts paid to other utilities and energy suppliers for purchased power. Purchased power contracts pertain to agreements made with other utilities and energy suppliers for purchased power to meet system load and energy requirements, replace generation from company-owned units under maintenance and during outages, and meet operating reserve obligations.
Purchased Power Contracts Costs [Member]
Renewable And Environmental Initiative Costs Member
Government mandated renewable energy and environmental costs which are deferred as regulatory assets due to the probability that the costs will be recovered from customers in future rates.
Renewable and Environmental Initiative Costs [Member]
Conservation Programs Member
Costs related to electric and natural gas conservation improvement programs, which would otherwise be charged to expense, are deferred as regulatory noncurrent assets based on the expected ability to recover them in future rates.
Conservation Programs [Member]
Contract Valuation Adjustments Member
Fair value adjustments pertaining to certain long-term purchased power agreements used to meet energy capacity requirements.
Contract Valuation Adjustments [Member]
Pension And Employee Benefit Obligations Member
Discloses the amount of the regulatory asset arising from the difference between net periodic pension cost and other employee benefit obligations and the amount of pension cost and other employee benefit obligations considered for rate-making purposes, according the actions of the regulator.
Pension and Employee Benefit Obligations [Member]
Schedule Of Regulatory Assets And Liabilities Text Block
The entire disclosure for detailed information about regulatory assets and liabilities, including current and noncurrent assets created when regulatory agencies permit the deferral of costs to the balance sheet that would otherwise be required to appear on the company's income statement and would be charged against current expenses or revenues, as well as current and noncurrent liabilities created when regulatory agencies permit.
Components of unamortized regulatory assets and liabilities of continuing operations
Regulatory Assets And Liabilities Text Block
Contains the components of unamortized regulatory assets and liabilities of continuing operations by remaining amortization period as shown on the balance sheets per ASC 980 Regulated Operations. Regulatory assets and liabilities represent amounts that may be collectible from, or required to be paid back to, customers in future gas and electric rates. This element may be used as a single block of text to encapsulate the entire disclosure for regulatory assets and liabilities including data and tables.
Regulatory Assets and Liabilities
Available For Sale Securities Gross Unrealized Losses1
This item represents the gross unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.
Unrealized losses
Available For Sale Securities Gross Unrealized Gain
This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.
Unrealized gains
Foreign Securities Member
This category includes information about debt securities which are issued by a national, local, or municipal government or foreign corporate entity with a promise of repayment. Foreign debt securities are issuances by governments or corporations outside the reporting entity's country of domicile.
Foreign Securities [Member]
International Equity Funds Member
This category includes information about ownership interests in equity funds whose investment portfolio consists mainly of securities outside the reporting entity's country of domicile.
International Equity Funds [Member]
Commingled Fund Member
This category includes information about ownership interests in funds whose investment portfolio consists many different types of securities.
Commingled Funds [Member]
Nuclear Decommissioning Expense Net
Net externally funded and internally funded (including interest costs) nuclear decommissioning expense reported as depreciation expense.
Net decommissioning expense recorded
Nuclear Decommissioning Expense Internally Funded Including Interest Costs
Nuclear decommissioning expense internally funded (including interest costs) and reported as depreciation expense.
Internally funded (including interest costs)
Nuclear Decommissioning Expense Externally Funded
Nuclear decommissioning expense externally funded and reported as depreciation expense.
Externally funded
Annual Decommissioning Cost Expense Reported As Depreciation Expense Abstract
Annual decommissioning cost expense reported as depreciation expense: [Abstract]
Effect Of Escalating Costs To Payment Date
Increase in estimated decommissioning cost obligation due to the effect of escalating costs to anticipated payment date.
Effect of escalating costs to payment date (2.89 percent per year)
Effect Of Escalating Costs To Current Year Dollars
Increase in estimated decommissioning cost obligation due to the effect of escalating costs to current year dollars.
Effect of escalating costs (to 2010 and 2009 dollars, respectively, at 2.89 percent per year)
Estimated Decommissioning Cost Obligation From Most Recently Approved Study
Estimated decommissioning cost obligation based on most recently approved periodic site-specific cost study.
Estimated decommissioning cost obligation (2008 dollars)
Nuclear Decommissioning Obligation Funded Status Abstract
Nuclear Decommissioning Obligation Funded Status [Abstract]
Cumulative Decommissioning Expense Recorded And Recovered In Rates
Cumulative amount of decommissioning expense recorded and recovered in customer rates by NSP-Minnesota.
Cumulative decommissioning expense recorded and recovered in rates by NSP-Minnesota
External Funds Held In Escrow Associated With Nuclear Plant Not Authorized For Refund
Amount of external funds held in escrow authorized by the Minnesota Public Utility Commission to entity's retail jurisdiction customers in Minnesota and subsequently refunded.
Authorized amount withdrawn from escrow not yet refunded to Wisconsin and Michigan customers, associated with Monticello nuclear plant
External Funds Held In Escrow Associated With Nuclear Plant Authorized For Refund
Amount of external funds held in escrow authorized by the Minnesota Public Utility Commission to NSP-Minnesota's retail jurisdiction customers in Minnesota and subsequently refunded.
Authorized amount withdrawn from escrow and refunded to Minnesota customers, associated with the Moticello nuclear plant
Assumed Rate Of Return On External Decommissioning Cost Funding Net Of Tax
Assumed rate of return on the external decommissioning trust fund, net of tax, used in annuity approach to determine total obligation for nuclear decommissioning costs.
Assumed rate of return on external decommissioning trust fund, net of tax (in hundredths)
Assumed Annual Escalation Rate Of Decommissioning Costs
Assumed rate of annual increase in decommissioning costs based on periodic site-specific cost studies.
Assumed annual escalation rate of decommissioning costs ( in hundredths)
Percentage Of Total Obligation For Decommissioning Expected To Be Funded By External Funds
Percentage of total obligation for decommissioning nuclear facilities expected to be funded by external decommissioning trust fund.
Percentage of total obligation for decommissioning expected to be funded by the external decommissioning trust fund (in hundredths)
Number Of Additional Contentions Denied By Atomic Safety And Licensing Board
Number of additional contentions filed by the Prairie Island Indian Community and denied by the Atomic Safety and Licensing Board in connection with NSP-Minnesota's application to renew the operating lease of its nuclear reactors at the Prairie Island nuclear plant with the Nuclear Regulatory Commission.
Number of additional contentions filed by the PIIC and denied by the ASLB
Number Of Additional Contentions Filed By Piic And Admitted By Aslb
Number of additional contentions filed by the Prairie Island Indian Community and admitted by the Atomic Safety and Licensing Board in connection with NSP-Minnesota's application to renew the operating lease of its nuclear reactors at the Prairie Island nuclear plant with the Nuclear Regulatory Commission.
Number of additional contentions filed by the PIIC and admitted by the ASLB
Number Of Additional Contentions Filed By Piic
Number of additional contentions filed by the Prairie Island Indian Community subsequent to the Nuclear Regulatory Commission's issuance of the final Safety Evaluation Report and the draft supplemental environmental impact statement.
Number of additional contentions filed by the PIIC
Number Of Contentions Filed By Piic
Number of contentions filed by the Prairie Island Indian Community in connection with NSP-Minnesota's application to renew the operating lease of its nuclear reactors at the Prairie Island nuclear plant with the Nuclear Regulatory Commission.
Number of contentions filed by the PIIC
Number Of Contentions Filed By Piic And Admitted By Aslb
Number of contentions filed by the Prairie Island Indian Community and admitted by the Atomic Safety and Licensing Board in connection with NSP-Minnesota's application to renew the operating lease of its nuclear reactors at the Prairie Island nuclear plant with the Nuclear Regulatory Commission.
Number of contentions filed by the PIIC and admitted by the ASLB
Number Of Years Of Extended Operation At Nuclear Plant Included In Operating License Renewal Application
Number of years of additional service included in Prairie Island nuclear facility application to renew operating license.
Number of years of extended operation at Prairie Island nuclear plant included in operating license renewal application (in years)
Number Of Nuclear Reactors
Number of nuclear reactors at the Prairie Island nuclear facility.
Number of nuclear reactors at Prairie Island
Number Of Authorized Canisters In Dry Cask Nuclear Storage Facility
Number of canisters authorized by the Minnesota Public Utility Commission to be placed in the Monticello dry-cask nuclear storage facility.
Number of authorized canisters in Monticello dry-cask nuclear storage facility
Number Of Authorized Canisters Filled And Placed In Dry Cask Nuclear Storage Facility
Number of canisters authorized by the Minnesota Public Utility Commission that have been filled and placed in the Monticello dry-cask nuclear storage facility.
Number of authorized canisters filled and placed in Monticello dry-cask nuclear storage facility
Number Of Years Of Extended Operation At Nuclear Plant
Number of years operating license and CON for spent fuel capacity were extended for the Monticello nuclear plant.
Number of years of extended operation at Monticello nuclear plant (in years)
Regulatory Plant Decommissioning Recovery Abstract
Regulatory Plant Decommissioning Recovery [Abstract]
Cumulative Fuel Disposal Assessment Paid To Doe
Cumulative amount paid by entity to the Department of Energy in connection with the Department of Energy's permanent nuclear disposal program.
Cumulative fuel disposal assessment paid to DOE
Doe Fuel Disposal Assessment Included In Fuel Expense
Amount paid by the entity to the Department of Energy during the period in connection with the Department of Energy's permanent nuclear disposal program.
DOE fuel disposal assessment included in fuel expense
Fuel Disposal Fee Charge
Fuel disposal fee associated with the Department of Energy's permanent nuclear disposal program based on a charge per KWh sold to customers from nuclear generation.
Fuel disposal fee charge per KWh
Fuel Disposal Abstract
Fuel Disposal [Abstract]
Nuclear Decommissioning Expenses Recognized Disclosure Text Block
Summary of the components of nuclear decommissioning expense reported as depreciation expense.
Nuclear Decommissioning Expenses Recognized
Nuclear Decommissioning Obligation Disclosure Text Block
Summary of the nuclear decommissioning obligation related to the nuclear facilities.
Summary of Funded Status of NSP-Minnesota's Nuclear Decommissioning Obligation Based on Approved Regulatory Recovery Parameters
Nuclear Obligations Text Block
Summarizes the requirements of nuclear fuel storage, disposal and decontamination programs as required by various regulators and governmental entities, which are recovered through customer rates. This can include total estimated, actual and forecasted obligation expenses, which are approved by regulatory authorities periodically. This element may be used as a single block of text to encapsulate the entire disclosure for nuclear obligations including data and tables.
Nuclear Obligations
Number Of Plaintiffs In Lawsuit
The number of plaintiffs in a lawsuit filed in Hennepin County District Court in Minneapolis, Minnesota, alleging personal injury and property damage as a result an explosion in Pueblo, Colorado, which destroyed a tavern and a neighboring store.
Number of plaintiffs in lawsuit related to explosion in Pueblo, Colorado
Number Of People Injured In Explosion
The number of people injured in an explosion in Pueblo, Colorado, which destroyed a tavern and a neighboring store.
Number of people injured in explosion in Pueblo, Colorado
Number Of People Killed In Explosion
The number of people killed in an explosion in Pueblo, Colorado, which destroyed a tavern and a neighboring store.
Number of people killed in explosion in Pueblo, Colorado
Maximum Insurance Coverage Under Professional Liability Policy
Maximum insurance coverage under Utility Engineering Corporation's professional liability policy for damages related to the construction of a natural gas-fired, combined-cycle power plant in Sacramento County.
Insurance coverage under professional liability policy
Net Verdict To Plaintiff
Amount of the net verdict to the contractor.
Net verdict to Shaw
Jury Award To Company
The amount awarded by jury to the entity for damages related to its counterclaims.
Jury award to PSCo
Jury Award To Plaintiff
The amount of damages awarded by jury to the contractor.
Jury award to Shaw
Damages Sought By Company
The amount of damages claimed by the entity against the contractor in a filed answer and counterclaim.
Damages sought by the entity against Shaw
Damages Sought By Contractor
The amount of losses claimed by contractor.
Damages claimed by Shaw
Alleged Guarantee Of Future Profits
The amount of guarantee of future profits which was allegedly made by the entity.
Alleged guarantee of future profits (Shaw)
Number Of Motions Filed To Dismiss Misdemeanor Counts Charged In Federal Court In Colorado For Violation Of Regulation Arrising From Hydro Generating Station Accident
The number of motions to dismiss misdemeanor counts charged in federal court in Colorado for violation of an OSHA regulation related to an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of motions filed to dismiss misdemeanor counts charged in federal court in Colorado for violation of OSHA regulation arising from hydro generating station accident
Number Of Individuals Employed By Contractor Indicted In Federal Court In Colorado For Violation Of Regulation Arrising From Hydro Generating Station Accident
The number of employees employed by contractor indicted in federal court in Colorado for violation of an OSHA regulation related to an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of individuals employed by contractor indicted in federal court in Colorado for violation of OSHA regulation arising from hydro generating station accident
Number Of Misdemeanor Counts Charged In Federal Court In Colorado For Violation Of Regulation Arrising From Hydro Generating Station Accident
The number of misdemeanor counts charged in federal court in Colorado for violation of an OSHA regulation related to an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of misdemeanor counts charged in federal court in Colorado for violation of OSHA regulation arising from hydro generating station accident
Number Of Lawsuits Arrising From Hydro Generating Station Accident
The number of lawsuits arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of lawsuits arising from hydro generating station accident
Number Of Contractors Named As Defendants In Lawsuit In California State Court Arrising From Hydro Generating Station Accident
The number of contractors named as defendants in a lawsuit in California state court arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of contractors named as defendants in lawsuit in California state court arising from hydro generating station accident
Number Of Deceased Workers Represented As Plaintiffs In Lawsuit In California State Court Arrising From Hydro Generating Station Accident
The number of deceased workers represented as plaintiffs in a lawsuit in California state court arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of deceased workers represented as plaintiffs in lawsuit in California state court arising from hydro generating station accident
Number Of Employees Represented As Plaintiffs In Lawsuit In Colorado State Court Arrising From Hydro Generating Station Accident
The number of employees allegedly injured and represented as plaintiffs in a lawsuit in Colorado state court arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of employees represented as plaintiffs in lawsuit in Colorado state court arising from hydro generating station accident
Number Of Contractors Named As Defendants In Lawsuit In Colorado State Court Arrising From Hydro Generating Station Accident
The number of contractors named as defendants in a lawsuit in Colorado state court arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of contractors named as defendants in lawsuit in Colorado state court arising from hydro generating station accident
Number Of Injured Workers Represented As Plaintiffs In Lawsuit In Colorado State Court Arrising From Hydro Generating Station Accident
The number of injured workers represented as plaintiffs in a lawsuit in Colorado state court arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of injured workers represented as plaintiffs in lawsuit in Colorado state court arising from hydro generating station accident
Number Of Deceased Workers Represented As Plaintiffs In Lawsuit In Colorado State Court Arrising From Hydro Generating Station Accident
The number of deceased workers represented as plaintiffs in a lawsuit in Colorado state court arising from an accident at PSCo's Cabin Creek Hydro Generating Station.
Number of deceased workers represented as plaintiffs in lawsuit in Colorado state court arising from hydro generating station accident
Alleged Number Of Willful Violations Proposed In Hydro Generating Station Accident
The alleged number of willful violations proposed by OSHA resulting from an accident at PSCo's Cabin Creek Hydro Generating Station.
Alleged number of willful violations proposed by OSHA in hydro generating station accident
Alleged Number Of Serious Violations Proposed In Hydro Generating Station Accident
The alleged number of serious violations proposed by OSHA resulting from an accident at PSCo's Cabin Creek Hydro Generating Station.
Alleged number of serious violations proposed by OSHA in hydro generating station accident
Penalities Proposed In Hydro Generating Station Accident
The proposed penalty for an accident from the Occupational Safety and Health Administration.
Proposed penalty by OSHA in hydro generating station accident
Number Of Deaths In Hydro Generating Station Accident
The number of deaths resulting from an accident at PSCo's Cabin Creek Hydro Generating Station..
Number of deaths in hydro generating station accident
Maximim Damages Entitled
The maximum amount of damages the Department of Energy claims NSP-Minnesota is entitled.
Maximum damages DOE claims the entity is entitled
Damages Suffered In Nuclear Waste Disposal Litigation
The amount of damages suffered by NSP-Minnesota in nuclear waste disposal litigation.
Damages suffered in nuclear waste disposal litigation
Damages Awarded In Nuclear Waste Disposal Litigation
The amount of damages awarded to the entity in nuclear waste disposal litigation.
Damages awarded to the entity in nuclear waste disposal litigation
Minimum Damages Claimed In Nuclear Waste Disposal Litigation
The minimum amount of damages claimed by the entity in nuclear waste disposal litigation.
Minimum damages claimed in nuclear waste disposal litigation
Number Of Insurers Who Commenced Litigation
The number of insurers who commenced litigation in lieu of participating in discussions regarding the availability of insurance coverage for costs associated with the remediation of former MGP sites.
Number of insurers who commenced litigation
Number Of Former Sites With Remediation
The number of sites with remediation costs for which insurance coverage is sought.
Number of former MGP sites with remediation
Damages Awarded By Jury
The amount of damages awarded to an employee of the entity in litigation and for which the entity is not liable.
Damages awarded by jury against Qwest who was solely liable
Loss Contingency Losses Claimed
The minimum amount of losses claimed by the owners and operators of a Minnesota dairy farm.
Losses claimed by plaintiffs
Employment Tort And Commercial Litigation Abstract
Employment, Tort and Commercial Litigation [Abstract]
Number Of Other Additional Utilities Oil Gas And Coal Companies Against Which Lawsuits Were Filed
The number of other utilities, oil, gas and coal companies in addition to Xcel Energy against which lawsuits were filed, claiming that defendants' emission of CO2 and other GHGs contribute to global warming, which is harming their village
Number of other additional utilities, oil, gas and coal companies against which lawsuits were filed
Number Of Oil Chemical And Utility Companies Named In Lawsuit
The number of oil, chemical and utility companies named in the lawsuit.
Number of oil, chemical and utility companies named in lawsuit
Number Of Utilities Against Which Lawsuits Were Filed
The number of utilities against which lawsuits were filed to force reductions in CO2 emissions.
Number of utilities against which lawsuits were filed
Number Of States Whose Attorneys General Filed Lawsuits
The number of states whose attorneys general filed lawsuits to force reductions in CO2 emissions.
Number of states whose attorneys general filed lawsuits
Number Of Lawsuits Filed
The number of lawsuits filed against e prime and Xcel Energy (and NSP-Wisconsin, in one instance); alleging fraud and anticompetitive activities in conspiring to restrain the trade of natural gas and manipulate natural gas prices.
Number of lawsuits filed against e prime and the Company
Environmental Litigation Abstract
Environmental Litigation [Abstract]
Maximum Assessment For Property Damage Insurance
The maximum assessment for property damage insurance per calendar year if losses exceed accumulated reserve funds.
Maximum assessment for property damage insurance each calendar year
Maximum Assessments For Business Interruption Insurance
The maximum assessments for business interruption insurance per calendar year if losses exceed accumulated reserve funds.
Maximum assessments for business interruption insurance each calendar year
Number Of Nuclear Plant Sites
The number of nuclear plant sites operated by the entity.
Number of nuclear plant sites operated by NSP-Minnesota
Insurance Coverage Limits For Nuclear Plant Sites
Insurance coverage limits for property damage and site decontamination cleanup costs for each of the nuclear plant sites.
Insurance coverage limits for property damage and site decontamination cleanup costs per nuclear plant sites
Maximum Funding Requirement Per Reactor For Any One Year
The annual maximum installment payment the company is subject to until either the maximum assessment has been reached or the claim has been met.
Maximum funding requirement per reactor for any one year
Number Of Licensed Reactors Operated
The number of licensed reactors operated by the company.
Number of licensed reactors owned
Maximum Assessments Per Reactor Per Accident
The maximum assessment the company is subject to for each reactor per accident incurred at any licensed nuclear facility within the United States, collected in annual installments.
Maximum assessments per reactor per accident
Nuclear Insurance Coverage Exposure Funded By Secondary Financial Protection Program
The amount of coverage secured for the public liability exposure thru the Secondary Financial Protection Program, available from assessments by the federal government in case of a nuclear accident.
Nuclear insurance coverage secured for public liability exposure thru the Secondary Financial Protection Program
Nuclear Insurance Coverage Secured For Public Liability Exposure
The amount of coverage secured for the public liability exposure thru a pool of insurance companies.
Nuclear insurance coverage secured for public liability exposure thru a pool of insurance companies
Nuclear Insurance Abstract
Nuclear Insurance [Abstract]
Asset Retirement Obligation Period Increase Decrease Nuclear
Net increase (decrease) in the asset retirement obligation related to nuclear production decommissioning and the related regulatory asset.
Decrease in the nuclear production decommissioning ARO and related regulatory asset due to the revised end of life date
Asset Retirement Obligations Line Items
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Asset Retirement Obligations [Line Items]
Common And Other Property Common General Plant Asbestos Member
Asset retirement obligations for general plant asbestos assets associated with common and other plant.
Common and Other Property - Common General Plant Asbestos [Member]
Natural Gas Plant Gas Transmission And Distribution Member
Asset retirement obligations for transmission and distribution assets associated with natural gas plant.
Natural Gas Plant - Gas Transmission and Distribution [Member]
Electric Plant Electric Transmission And Distribution Member
Asset retirement obligations for transmission and distribution assets associated with electric plant.
Electric Plant - Electric Transmission and Distribution [Member]
Electric Plant Wind Production Member
Asset retirement obligations for wind production assets associated with electric plant.
Electric Plant - Wind Production [Member]
Electric Plant Nuclear Production Decommissioning Member
Asset retirement obligations for nuclear production decommissioning assets associated with electric plant.
Electric Plant - Nuclear Production Decommissioning [Member]
Electric Plant Steam Production Radiation Sources Member
Asset retirement obligations for steam production radiation sources assets associated with electric plant.
Electric Plant - Steam Production Radiation Sources [Member]
Electric Plant Steam Production Ash Containment Member
Asset retirement obligations for steam production ash containment assets associated with electric plant.
Electric Plant - Steam Production Ash Containment [Member]
Electric Plant Steam Production Asbestos Member
Asset retirement obligations for steam production asbestos assets associated with electric plant.
Electric Plant - Steam Production Asbestos [Member]
Asset Retirement Obligations Domain
The specific class of property for which the company has recorded an asset retirement obligation.
Asset Retirement Obligations by Class of Property [Domain]
Asset Retirement Obligations Axis
The company's asset retirement obligations by class of property.
Asset Retirement Obligations by Class of Property [Axis]
Asset Retirement Obligations Table
Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation.
Asset Retirement Obligations [Table]
Number Of Nuclear Generating Plants
The number of nuclear generating plants owned by the Company.
Number of nuclear generating plants
Recorded Aro Abstract
Recorded Asset Retirement Obligation [Abstract]
Proposed Penalty Included In Final Compliance Order
The penalty included in the final compliance order from the New Mexico Environment Department.
Penalty included in final compliance order
Proposed Penalty Included In Draft Compliance Order
The proposed penalty for the Cunningham Station included in the draft compliance order from the New Mexico Environment Department.
Proposed penalty included in draft compliance order
Draft Compliance Order Abstract
Cunningham Compliance Order [Abstract]
Environmental Compliance Annual Sorbent Expense Estimate
The cost of materials used to absorb liquids or gases associated with environmental compliance.
Estimated annual sorbent expense
Environmental Compliance Cost Of Capital Additions
The cost of capital improvements associated with environmental compliance.
Estimated capital cost
Minimum Percent Of Mercury Which Must Be Captured
Minimum percent of mercury which must be captured due to Colorado's mercury regulations.
Minimum percent of mercury which must be captured
Colorado Mercury Regulation Abstract
Colorado Mercury Regulation [Abstract]
Number Of Years Before The Epa Will Require Affected Facilities To Demonstrate Compliance, High End Of Range
Number of years before the EPA will require affected facilities to demonstrate compliance, high end of range (in years)
The upper end of the range of number of years before the United States Environmental Protection Agency will require affected facilities to demonstrate compliance.
Number Of Years Before The Epa Will Require Affected Facilities To Demonstrate Compliance, Low End Of Range
Number of years before the EPA will require affected facilities to demonstrate compliance, low end of range (in years)
The lower end of the range of number of years before the United States Environmental Protection Agency will require affected facilities to demonstrate compliance.
Clean Air Mercury Rule Abstract
Clean Air Mercury Rule [Abstract]
Loss Contingency Loss Estimate Compliance Costs Current Year
The estimated compliance cost that will be charged against the earnings of Northern States Power Company of Wisconsin for the loss contingency in the current year for environmental compliance, which estimate is as of the balance sheet date, proposed by environmental legislation under consideration by the U.S. Congress.
NOx allowance costs for NSP-Wisconsin
Annual Purchases Of So 2 Allowances High End Of Range
The high end of the estimate as of the balance sheet date of annual purchases of SO2 allowances, beginning in a future period, for environmental compliance by Southwestern Public Service Company, proposed by environmental legislation under consideration by the U.S. Congress.
Annual purchases of SO2 allowances for phase I by SPS
Loss Contingency Loss Estimate Nox Compliance Costs Current Year
The estimated compliance cost that will be charged against the earnings of Southwestern Public Service Company for the loss contingency in the current year for environmental compliance, which estimate is as of the balance sheet date, proposed by environmental legislation under consideration by the U.S. Congress.
NOx allowance compliance costs for SPS
Estimated Capital Investments Required
The compliance cost that was charged against the earnings of Southwestern Public Service Company for the loss contingency in a prior period for environmental compliance proposed by environmental legislation under consideration by the U.S. Congress.
Remaining capital investments for NOx controls by SPS
Number Of States Requiring So2 And Nox Reductions In Proposed Clean Air Transport Rule Issued By Epa
The number of states requiring SO2 and NOx reductions in the proposed Clean Air Transport Rule issued by the EPA.
Number of states requiring SO2 and NOx reductions in the proposed Clean Air Transport Rule issued by the EPA
Clean Air Interstate Rule Abstract
Clean Air Interstate Rule [Abstract]
Recorded Liability To Remediate Site
NSP-Wisconsin's recorded liability to remediate the Ashland MGP site based upon potential remediation and design costs together with estimated outside legal and consultant costs.
Estimated cost of remediating sites
Variance Between Epa Estimated And Actual Project Costs Low End Of Range
Low end of range of the variance between EPA's proposed remedial action plan cost estimated and actual project costs for site remediation
Variance between EPA's estimated and actual proposed remedial action plan costs, low end of range (in hundredths)
Variance Between Epa Estimated And Actual Project Costs High End Of Range
High end of range of the variance between EPA's proposed remedial action plan cost estimated and actual project costs for site remediation
Variance between EPA's estimated and actual proposed remedial action plan costs, high end of range (in hundredths)
Loss Contingency Damages Claimed High End Of Range
The estimated high end of the range of possible loss claimed.
Proposed remedial action plan cost, high end of range
Loss Contingency Damages Claimed Low End Of Range
The estimated low end of the range of possible loss claimed.
Proposed remedial action plan cost, low end of range
Ashland Mgp Site Abstract
Ashland MGP Site [Abstract]
Site Remediation [ Abstract]
Site Remediation [Abstract]
Percent Of Contract Value To Be Paid If Contract Is Terminated
Percent of contract value to be paid if contract is cancelled by entity.
Percent of contract value to be paid if contract is terminated
Technology Services Costs Other Project Business
Costs incurred in providing technology services for other project business. The services may include training, installation, engineering or consulting. Consulting services often include implementation support, software design or development, or the customization or modification of the licensed software.
Amount paid for other project business
Long Term Purchase Commitment Technology Agreement Future Minimum Payments Due After Four Years
For technology service agreements having initial or remaining terms in excess of one year, required payments due after the fourth year of the balance sheet date.
2015 and thereafter
Long Term Purchase Commitment Technology Agreement Future Minimum Payments Due In Four Years
For technology service agreements having initial or remaining terms in excess of one year, required payments due within the fourth year of the balance sheet date.
2014
Long Term Purchase Commitment Technology Agreement Future Minimum Payments Due In Three Years
For technology service agreements having initial or remaining terms in excess of one year, required payments due within the third year of the balance sheet date.
2013
Long Term Purchase Commitment Technology Agreement Future Minimum Payments Due In Two Years
For technology service agreements having initial or remaining terms in excess of one year, required payments due within the second year of the balance sheet date.
2012
Long Term Purchase Commitment Future Minimum Payments Due Current
For technology service agreements having initial or remaining terms in excess of one year, required payments due within one year of the balance sheet date.
2011
Longterm Purchase Commitment Minimum Payments Due [Abstract]
Technology agreements, minimum payments due [Abstract]
Accenture Agreement Member
Contractual obligation to purchase information technology services from Accenture over periods that initially exceed one year or the normal operating cycle, if longer.
Accenture Agreement [Member]
Ibm Agreement Member
Contractual obligation to purchase information technology services from International Business Machines Corp. over periods that initially exceed one year or the normal operating cycle, if longer.
IBM Agreement [Member]
Operating Lease By Class Line Items
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Operating Leases [Line Items]
Purchase Power Agreement Operating Leases Member
Represents future commitments under purchase power agreements that have been accounted for as operating leases.
Purchase Power Agreement Operating Leases [Member]
Other Operating Leases Member
Represents future commitments under other agreements that have been accounted for as operating leases.
Other Operating Leases [Member]
Operating Lease By Class Domain
The specific assets under operating lease agreements.
Operating Leases [Domain]
Operating Lease By Class Axis
The types of assets under operating lease agreements.
Operating Leases [Axis]
Operating Lease By Class Table
A listing of minimum payments by class of the type of property under an operating lease agreement.
Operating Leases [Table]
Capital Leases Lessee Balance Sheet Assets By Major Class Gas Pipeline
Gas pipeline assets that are subject to a lease meeting the criteria for capitalization.
Gas pipeline
Capital Leases Lessee Balance Sheet Assets By Major Class Storage Leaseholds And Rights
Storage, leaseholds, and rights that are subject to a lease meeting the criteria for capitalization.
Storage, leaseholds and rights
Number Of Capital Leases Held By Company
The number of capital leases held by a company.
Number of capital leases held by the company
Variable Interest Entity Consolidated Carrying Amount Liabilities
The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.
Total liabilities
Variable Interest Entity Consolidated Carrying Amount Other Noncurrent Liabilities
The carrying amount of the consolidated Variable Interest Entity's other noncurrent liabilities included in the reporting entity's statement of financial position.
Other noncurrent liabilities
Variable Interest Entity Consolidated Carrying Amount Mortgages Other Long Term Debt Payable
The carrying amount of the consolidated Variable Interest Entity's mortgages and other long-term debt payable included in the reporting entity's statement of financial position.
Mortgages and other long-term debt payable
Variable Interest Entity Consolidated Carrying Amount Current Liabilities
The carrying amount of the consolidated Variable Interest Entity's current liabilities included in the reporting entity's statement of financial position.
Current liabilities
Variable Interest Entity Consolidated Carrying Amount Assets
The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.
Total assets
Variable Interest Entity Consolidated Carrying Amount Other Noncurrent Assets
The carrying amount of the consolidated Variable Interest Entity's other noncurrent assets included in the reporting entity's statement of financial position.
Other noncurrent assets
Variable Interest Entity Consolidated Carrying Amount Property Plant Equipment Net
The carrying amount of the consolidated Variable Interest Entity's net property, plant and equipment included in the reporting entity's statement of financial position.
Property, plant and equipment, net
Variable Interest Entity Consolidated Carrying Amount Current Assets
The carrying amount of the consolidated Variable Interest Entity's current assets included in the reporting entity's statement of financial position.
Current assets
Variable Interest Entity Consolidated Carrying Amount Assets And Liabilities Abstract
Amounts Reflected in Consolidated Balance Sheets [Abstract]
Capacity Under Long Term Purchased Power Agreements With Variable Interest Entities
The capacity under long-term purchased power agreements with entities that have been determined to be variable interest entities.
Capacity under long-term purchased power agreements with variable interest entities (in MW)
Variable Interest Entities Abstract
Variable Interest Entities [Abstract]
Unrecorded Unconditional Purchase Obligation Estimated Future Payments Due In Six Years And Thereafter
The estimated future payments of an unrecorded unconditional purchase obligation due within the sixth year of the balance sheet date and thereafter.
2016 and thereafter
Unrecorded Unconditional Purchase Obligation Estimated Future Payments Due In Five Years
The estimated future payments of an unrecorded unconditional purchase obligation due within the fifth year of the balance sheet date.
2015
Unrecorded Unconditional Purchase Obligation Estimated Future Payments Due In Four Years
The estimated future payments of an unrecorded unconditional purchase obligation due within the fourth year of the balance sheet date.
2014
Unrecorded Unconditional Purchase Obligation Estimated Future Payments Due In Three Years
The estimated future payments of an unrecorded unconditional purchase obligation due within the third year of the balance sheet date.
2013
Unrecorded Unconditional Purchase Obligation Estimated Future Payments Due In Two Years
The estimated future payments of an unrecorded unconditional purchase obligation due within the second year of the balance sheet date.
2012
Unrecorded Unconditional Purchase Obligation Estimated Future Payments Due Current
The estimated future payments of an unrecorded unconditional purchase obligation due within one year of the balance sheet date.
2011
Estimated Future Payments For Capacity Abstract
Estimated Future Payments for Capacity [Abstract]
Expiration Date Of Fuel Contacts Maximum
The maximum expiration date of the unconditional purchase obligation that is not recorded as a liability on the balance sheet.
Expiration date of fuel contacts, maximum
Expiration Date Of Fuel Contacts Minimum
The minimum expiration date of the unconditional purchase obligation that is not recorded as a liability on the balance sheet.
Expiration date of fuel contacts, minimum
Fuel Contracts Member
Long-term purchase contracts providing for the purchase and delivery of a significant portion of its current coal, nuclear fuel and natural gas requirements.
Fuel Contracts [Member]
Natural Gas Storage And Transportation [Member]
An acquired natural gas storage and transportation agreement, providing benefits for a finite period of time, under which a power company contracts the storage capacity and delivery of its natural gas to meet the requirements of one of its power plants (under specified terms for specified time periods).
Natural Gas Storage and Transportation [Member]
Natural Gas Supply Agreements [Member]
An acquired natural gas supply agreement, providing benefits for a finite period of time, under which a power company buys natural gas to meet the requirements of one of its power plants (under specified terms for specified time periods).
Natural Gas Supply [Member]
Percent Of Capital Expenditures And Return On Investment For Transmission Projects Expected To Be Recovered
Percentage of capital expenditures and return on investment for transmission projects expected to be recovered under a transmission cost recovery tariff rider mechanism authorized by Minnesota legislation and a similar transmission cost recovery mechanism passed in South Dakota.
Percent of CapX2020 capital expenditures and return on investment for transmission projects expected to be recovered (in hundredths)
Estimated Project Investment Group1 Company Portion
Total estimated investment by the company for Group 1 transmission projects sponsored by CapX2020.
Company's portion of estimated investment in CapX2020 Group 1 projects
Number Of Group1 Projects
Total number of Group 1 projects.
Number of Group 1 projects
Number Of Group1 Projects Beginning Major Construction
Number of Group 1 projects beginning major construction.
Number of Group 1 projects beginning major construction
Total Estimated Investment In Group1 Projects
Total estimated investment in Group 1 transmission projects sponsored by CapX2020, an alliance of electric cooperatives, municipals and investor-owned utilities in the upper Midwest proposed to be complete by 2020.
Total estimated investment in CapX2020 Group 1 projects
Total Capacity Of Wind Generation Project In Southeastern North Dakota
Capacity (in megawatts) of a wind generation project under construction not yet in operations.
Total capacity of the Merricourt Wind Project in southeastern North Dakota (in MW)
Total Capacity Of Wind Generation Project In Southwestern Minnesota
Capacity (in megawatts) of a wind generation project in operation.
Total capacity of the Nobles Wind Project in southwestern Minnesota (in MW)
Number Of Years For Investment In Wind Generation Projects
Length of time (in years) in which the company plans to invest in wind generation projects in southwestern Minnesota and southeastern North Dakota.
Number of years for investment in wind generation projects (in years)
Investment In Wind Generation Projects
Represents the estimated total capital investment for wind generation projects in southwestern Minnesota and southeastern North Dakota at the end of 2011.
Total estimated investment in wind generation projects at end of 2011
Estimated Capital Investment For Life Extension And Capacity Increases At Nuclear Plants
The total estimated capital investment for the nuclear plants.
Estimated total capital investment for the Monticello and Prairie Island nuclear plants
Capacity Increases For Nuclear Plants
Total additional capacity (in megawatts) sought for nuclear plants.
Total capacity increases sought for Monticello and Prairie Island nuclear plants (in MW)
Term Of License Renewal For Nuclear Plant
Period of time the company seeks for a renewed license to operate a nuclear plant.
Term of license renewal for the Prairie Island nuclear plant (in years)
Capital Commitments Abstract
Capital Commitments [Abstract]
Leases Future Minimum Payments Due Text Block
Description of the total of future contractually required payments on leases defined as either operating or capital over the next five years and thereafter, including the interest component of the capital lease obligation, if applicable.
Future Commitments Under Operating and Capital Leases for Continuing Operations
Settlement Amount
The settlement amount agreed to resolve claims against the entity, approved by the Federal Energy Regulatory Commission.
Settlement amount for Cap Rock
Release Of Previously Established Reserve
Release of previously established reserve due to the Federal Energy Regulatory Commission approval of settlement.
Release of previously established reserve
Contingent Payment
Contingent payment to customers, subject to state approval.
Contingent payment
Formula Production Rate Of Return On Equity For New Mexico Cooperatives Settlement
Rate of return on equity agreed upon within the wholesale rate settlement, approved by the Federal Energy Regulatory Commission.
Formula production ROE for New Mexico Cooperatives' settlement (in hundredths)
Proposed Fuel Refund To Customers
The amount proposed for fuel refunds to customers, subject to approval by the Federal Energy Regulatory Commission.
Proposed fuel refund to customers
Proposed Base Rate Refund To Customers
The amount proposed for base rate refunds to customers, subject to approval by the Federal Energy Regulatory Commission.
Proposed base rate refund to customers
Wholesale Rate Complaints Abstract
Wholesale Rate Complaints
Percent Return On Equity
Rate of return on equity that the entity's approved revenue increase requested represented through a transmission formula rate case proceeding, filed with the Federal Energy Regulatory Commission in 2007.
Percent return on equity (in hundredths)
Transmission Formula Rate Case Abstract
Transmission Formula Rate Case
Federal Energy Regulatory Commission Transmission Formula Rate Case And Wholesale Rate Complaints Abstract
Federal Energy Regulatory Commission (FERC)
Initial Rate Of Return On Equity
Rate of return on equity to be earned subsequent to the sale of electric distribution system assets.
Initial ROE (in hundredths)
Initial ROE 9 (in hundredths)
Agreement To Sell Electric Distribution System Assets Amount
The revenue associated with the agreement to sell electric distribution system assets.
Sale of electric distribution system assets, amount
Lubbock Electric Distribution Assets Abstract
Lubbock Electric Distribution Assets
Sale of Lubbock Electric Distribution Assets [Abstract]
Fuel Cost Under Recovery
The amount by which fuel costs were under-recovered for prior years at December 31, 2009, recovery subject to approval by the Public Utility Commission of Texas.
Fuel cost under-recovery
Electric Rate Base
The entity's adjusted requested value established on which the entity is allowed to earn a particular rate of return on electric operations for 2011, filed with the Public Utility Commission of Texas.
Electric rate base
Equity Ratio
The ratio of equity to total capitalization (debt plus equity) used in the entity's adjusted requested electric rate regulatory proceeding for 2011, filed with the Public Utility Commission of Texas.
Equity ratio (in hundredths)
Rate Of Return On Equity
Rate of return on equity that the entity's adjusted revenue increase requested represented through an electric rate case proceeding for 2011, filed with the Public Utility Commission of Texas.
ROE (in hundredths)
Transmission Cost Recovery Factor
This element represents the exclusion of the Transmission Cost Recovery Factor rider related to the Public Utility Commission of Texas electric rate proposal.
Transmission cost recovery factor
Purchased Capacity Recovery Factor
This element represents the exclusion of the Purchased Capacity Recovery Factor rider related to the Public Utility Commission of Texas electric rate proposal.
Purchased capacity recovery factor
Nitrogen Oxide Emission Allowances
The increase in the base rates due to an adjustment for NOx emission allowances related to the Public Utility Commission of Texas electric rate proposal.
Nitrogen oxide (NOx) emission allowances
Franchise Fee Cost Recovery
The amount of franchise fee cost recovery that the entity has requested related to the Public Utility Commission of Texas electric rate proposal.
Franchise fee cost recovery
Proposed Rate Increase
The entity's unadjusted requested amount of increase (decrease) to existing electric rates for 2011, filed with the Public Utility Commission of Texas.
Proposed rate increase
Entitys Original Requested Percent Of Increase In Rates
The entity's original requested percent of increase (decrease) to existing electric rates for 2011, filed with the Public Utility Commission of Texas.
Entity's original requested percent of increase in rates (in hundredths)
Texas Retail Base Rate Case Abstract
SPS Texas Retail Base Rate Case
Public Utility Commission Of Texas Abstract
Public Utility Commission of Texas (PUCT)
Additional Step Rate Increase Implemented
The entity's implemented amount of increase (decrease) to existing wholesale rates for 2011 related to the recovery of property taxes, subject to approval by the Federal Energy Regulatory Commission.
Additional step rate increase implemented
Entitys Implemented Rate Increase Decrease
The entity's implemented amount of increase (decrease) to existing wholesale rates, subject to approval by the Federal Energy Regulatory Commission.
Entity's implemented rate increase (decrease)
Entitys Original Requested Rate Base Wholesale Rate Case
The ratio of equity to total capitalization (debt plus equity) used related to the entity's original requested wholesale rate proceeding for 2011, filed the Federal Energy Regulatory Commission.
Entity's original requested rate base
Entitys Original Requested Equity Ratio Percent Wholesale Rate Case
The entity's original requested value established on which the entity is allowed to earn a particular rate of return on wholesale operations for 2011, filed with the Federal Energy Regulatory Commission.
Entity's original requested equity ratio percent (in hundredths)
Entitys Original Requested Percent Return On Equity Wholesale Rate Case
Rate of return on equity that the entity's original revenue increase requested represented related to a wholesale rate proceeding for 2011, filed with the Federal Energy Regulatory Commission.
Entity's original requested percent return on equity (in hundredths)
Entitys Original Rate Increase Decrease Wholesale Rate Case
The entity's original requested amount of increase (decrease) to existing wholesale rates for 2011, filed with the Federal Energy Regulatory Commission.
Entity's original requested rate increase (decrease)
Wholesale Rate Case Abstract
Wholesale Rate Case
Federal Energy Regulatory Commission Wholesale Rate Case Abstract
Federal Energy Regulatory Commission (FERC)
Percent Of Increase In Rates By The Entity In Proposed Plan As Filed
The entity's annual percent of increase (decrease) to existing electric rates over the next ten years to be in compliance with the Colorado Clean Air-Clean Jobs Act, filed with the Colorado Public Utilities Commission.
Percent of increase in rates by the entity in proposed plan, as filed (in hundredths)
New Construction By The Entity In Proposed Plan As Filed
The entity's cost for new construction over the next twelve years to be in compliance with the Colorado Clean Air-Clean Jobs Act, filed with the Colorado Public Utilities Commission.
New construction by the entity in proposed plan, as filed
Colorado Clean Air Clean Jobs Act Abstract
Colorado Clean Air-Clean Jobs Act
Percentage Of Margin Associated With The Sale Of Stand- Alone Renewable Energy Credit To Go To Customers
This element represents the percentage of margins associated with the sale of stand-alone Renewable Energy Credit which will go to customers, approved by the Colorado Public Utilities Commission.
Percentage of margin associated with the sale of stand-alone RECs to go to customers (in hundredths)
Percentage Of Margin Associated With Renewable Energy Credit Bundled With Energy To Go To Customers
This element represents the percentage of margins associated with the Renewable Energy Credit bundled with energy that will go to the customers, approved by the Colorado Public Utilities Commission.
Percentage of margin associated with RECs bundled with energy to go to customers (in hundredths)
Percentage Of Margin Associated With Renewable Energy Credit Bundled With Energy To Go To The Entity
This element represents the percentage of margins associated with the Renewable Energy Credit bundled with energy which will go to the entity, approved by the Colorado Public Utilities Commission.
Percentage of margin associated with RECs bundled with energy to go to the entity (in hundredths)
Percentage Of Margin Related To Carbon Offsets, Returned To Customers After The Limit Reached
This element represents the percentage of margins related to carbon margins which will go to the customers after the cap is reached, approved by the Colorado Public Utilities Commission.
Percentage of margin related to carbon offsets, returned to customers after the limit reached (in hundredths)
Carbon Offset Cap
The maximum amount of regulatory liability for carbon offsets, approved by the Colorado Public Utilities Commission.
Carbon offset cap
Percentage Of Remaining Margins
This element represents the percentage of margins over $30 million which will go to customers during the pilot period.
Greater than $30 million (in hundredths)
Percentage Of First 10 Million On Margins
This element represents the percentage of the first $10 million of margins which will go to the entity during the pilot period.
Less than $10 million (in hundredths)
Settlement Margins Abstract
Settlement margins
Settlement Margins Line Items
Settlement Margins [Line Items]
Carbon Offsets Member
Carbon Offsets [Member]
Customers Member
Customers [Member]
Settlement Margins Domain
Settlement Margins [Domain]
Settlement Margins Axis
Settlement Margins [Axis]
Settlement Margins Table
Settlement Margins [Table]
Renewable Energy Credit Sharing Settlement Abstract
Renewable Energy Credit (REC) Sharing Settlement
Entitys Implemented Revenue Increase Decrease Due To Reduction In Base Rates
The entity's implemented amount of cost recovery, filed in the Transmission Cost Adjustment rider.
Entity's implemented revenue increase (decrease)
Transmission Cost Adjustment Rider Abstract
Transmission Cost Adjustment (TCA) Rider
Implemented Rate Increase
The entity's implemented amount of increase (decrease) to existing electric rates for 2011, approved by the Colorado Public Utilities Commission.
Implemented rate increase for 2011
Additional Approved Rate Increase
The entity's additional amount of the approved increase (decrease) to existing electric rates for 2011, approved by the Colorado Public Utilities Commission.
Additional approved rate increase
Implemented Rate Increase Phase 1
The entity's implemented amount of increase (decrease) to existing electric rates for phase 1, approved by the Colorado Public Utilities Commission.
Implemented rate increase - Phase 1
Approved Rate Increase
The entity's approved amount of increase (decrease) to existing electric rates for 2011, approved by the Colorado Public Utilities Commission.
Approved rate increase
Electric Rate Case 2010 Abstract
PSCo 2010 Electric Rate Case
Colorado Public Utilities Commission Abstract
Colorado Public Utilities Commission (CPUC)
Requested Rate Increase Decrease Monticello Nuclear Decommissioning Fund Refund
The entity's original requested amount of increase (decrease) to existing electric rates for 2010 related to the nuclear decommissioning fund refund, filed with the Public Service Commission of Wisconsin.
Monticello nuclear decommissioning fund refund
Requested Rate Increase Decrease Other
The entity's original requested amount of increase (decrease) to existing electric rates for 2010 related to other net costs, filed with the Public Service Commission of Wisconsin.
Other
Requested Rate Increase Decrease Fuel And Purchased Power
The entity's original requested amount of increase (decrease) to existing electric rates for 2010 related to fuel and purchased power, filed with the Public Service Commission of Wisconsin.
Fuel and purchased power
Requested Rate Increase Decrease Production And Transmission Fixed Charges
The entity's original requested amount of increase (decrease) to existing electric rates for 2010 related to production and transmission fixed charges, filed with the Public Service Commission of Wisconsin.
Production and transmission fixed charges
Requested Rate Increase Decrease Abstract
Cost components of requested increase
Entitys Original Requested Percent Of Increase In Rates Filed With Public Service Commission Of Wisconsin
The entity's original requested percent of increase (decrease) to existing electric rates for 2010, filed with the Public Service Commission of Wisconsin.
Entity's original requested percent of increase in rates (in hundredths)
Electric Rate Case Reopener Abstract
NSP-Wisconsin 2010 Electric Rate Case Reopener
Liability For Amounts Collected Subject To Refund
The liability accrued for amounts subject to refund if the entity were to exceed the cumulative variance range percentage for monitored fuel and purchased power costs established by the Public Service Commission of Wisconsin.
Liability for amounts collected subject to refund
Cumulative Variance Range For Monitored Fuel Costs
The cumulative variance range percentage for monitored fuel and purchased power costs established by the Public Service Commission of Wisconsin.
Cumulative variance range for monitored fuel costs
Percentage Of Fuel And Purchased Power Costs Lower Than Authorized
Approximate percent of fuel and purchased power costs lower than authorized in the 2010 electric rate case by the Public Service Commission of Wisconsin.
Percentage of fuel and purchased power costs lower than authorized (in hundredths)
Fuel And Purchased Power Costs Lower Than Authorized
Approximate amount of fuel and purchased power costs lower than authorized in the 2010 electric rate case by the Public Service Commission of Wisconsin.
Fuel and purchased power costs lower than authorized
Interest Rate On Refund
The interest rate to be applied to customer refunds.
Interest rate on refund (in hundredths)
Electric Fuel Cost Recovery Abstract
2010 Electric Fuel Cost Recovery
Public Service Commission Of Wisconsin Abstract
Public Service Commission of Wisconsin (PSCW)
Recovery From Customers Under Purchased Gas Adjustment
Recovery from customers under the purchased gas adjustment filed with the Minnesota Public Utilities Commission.
Recovery from customers under purchased gas adjustment
Recovery From Customers Under Fuel Clause Adjustment
Recovery from customers under the fuel clause adjustment filed with the Minnesota Public Utilities Commission .
Recovery from customers under fuel clause adjustment
Annual Automatic Adjustment Report Abstract
Annual Automatic Adjustment Report
Revenue Increase Decrease Requested Renewable Development Fund Rider
The amount of revenue increase (decrease) requested for the Renewable Development Fund rider for 2011, filed with the Minnesota Public Utilities Commission.
Revenue increase (decrease) requested
Revenue Increase Decrease Implemented Renewable Development Fund Rider
The amount of revenue increase (decrease) approved for the Renewable Development Fund rider for 2010, approved by the Minnesota Public Utilities Commission.
Revenue increase (decrease) approved
Renewable Development Fund Rider Abstract
Renewable Development Fund (RDF) Rider
Revenue Increase Decrease Requested Metropolitan Emissions Reduction Project Rider
The amount of revenue increase (decrease) requested for to the recovery of revenue requirements related to environmental improvement projects for 2011, filed with the Minnesota Public Utilities Commission.
Revenue increase (decrease) requested
Revenue Increase Decrease Implemented Metropolitan Emissions Reduction Project Rider
The amount of revenue increase (decrease) approved for to the recovery of revenue requirements related to environmental improvement projects for 2010, approved by the Minnesota Public Utilities Commission.
Revenue increase (decrease) implemented
Metropolitan Emissions Reduction Project Rider Abstract
Metropolitan Emissions Reduction Project (MERP) Rider
Implemented Recovery Of Natural Gas Retail Revenue Requirements
The amount of revenue increase (decrease) associated with the implemented recovery of natural gas retail revenue requirements in compliance with the State Energy Policy rider.
Implemented recovery of natural gas retail revenue requirements
Implemented Recovery Of Electrical Retail Revenue Requirements
The amount of revenue increase (decrease) associated with the implemented recovery of electrical retail revenue requirements in compliance with the State Energy Policy rider.
Implemented recovery of electrical retail revenue requirements
State Energy Policy Rider Abstract
State Energy Policy (SEP) Rider
Revenue Increase Decrease Requested Renewable Energy Standard Rider
The amount of revenue increase (decrease) requested related to the Renewable Energy Standard rider for 2011, filed with the Minnesota Public Utilities Commission
Revenue increase (decrease) requested
Revenue Increase Decrease Implemented
The amount of revenue increase (decrease) resulting from the Renewable Energy Standard rider for 2010, approved by the Minnesota Public Utilities Commission.
Revenue increase (decrease) implemented
Renewable Energy Standard Rider Abstract
Renewable Energy Standard (RES) Rider
Revenue Increase Decrease Requested Transmission Cost Recovery Rider
The amount of revenue increase (decrease) requested for the Transmission Cost Recovery rider for 2011, filed with the Minnesota Public Utilities Commission.
Revenue increase (decrease) requested
Costs Approved Not Approved
The amount of revenue increase (decrease) not approved for recovery related to the Transmission Cost Recovery rider for 2010 by the Minnesota Public Utilities Commission.
Costs approved (not approved)
Revenue Increase Decrease Approved
The amount of revenue increase (decrease) resulting from the Transmission Cost Recovery rider for 2010, approved by the Minnesota Public Utilities Commission.
Revenue increase (decrease) implemented
Transmission Cost Recovery Rider Abstract
Transmission Cost Recovery (TCR) Rider
Administrative Law Judges Recommendation For Percent Returnon Equity
Rate of return on equity that the administrative law judge's revenue increase represented through a gas rate case proceeding for 2010.
Administrative law judge's recommendation for percent return on equity (in hundredths)
Administrative Law Judges Recommendation For Rate Increase Decrease
The administrative law judge's recommended amount of increase (decrease) to existing gas rates for 2010.
Administrative law judge's recommendation for rate increase (decrease)
Office Of Energy Securitys Revised Recommendation For Percent Return On Equity
Rate of return on equity that the Office of Energy Security's revised revenue increase represented through a gas rate case proceeding for 2010, filed with the Minnesota Public Utilities Commission.
Office of Energy Security's revised recommendation for percent return on equity (in hundredths)
Office Of Energy Securitys Revised Recommendation For Rate Increase Decrease
The Office of Energy Security's revised recommended amount of increase (decrease) to existing gas rates for 2010, filed with the Minnesota Public Utilities Commission.
Office of Energy Security's revised recommendation for rate increase (decrease)
Entitys Revised Percent Return On Equity
Rate of return on equity that the entity's revised revenue increase requested represented through a gas rate case proceeding for 2010, filed with the Minnesota Public Utilities Commission.
Entity's revised percent return on equity (in hundredths)
Entitys Revised Rate Increase Decrease
The entity's revised requested amount of increase (decrease) to existing gas rates for 2010, filed with the Minnesota Public Utilities Commission.
Entity's revised rate increase (decrease)
Office Of Energy Securitys Original Recommendation For Percent Return On Equity
Rate of return on equity that the Office of Energy Security's original revenue increase represented through a gas rate case proceeding for 2010, filed with the Minnesota Public Utilities Commission.
Office of Energy Security's original recommendation for percent return on equity (in hundredths)
Office Of Energy Securitys Original Recommendation For Rate Increase Decrease
The Office of Energy Security's original recommended amount of increase (decrease) to existing gas rates for 2010, filed with the Minnesota Public Utilities Commission.
Office of Energy Security's original recommendation for rate increase (decrease)
Interim Rate Increase Implemented
The interim gas rate increase (decrease) implemented for 2010, approved by the Minnesota Public Utilities Commission.
Interim rate increase implemented
Entitys Original Requested Recovery Of Pension Funding Costs
The entity's original requested amount of recovery for pension funding costs for 2011, filed with the Minnesota Public Utilities Commission.
Entity's original requested recovery of pension funding costs
Entitys Original Requested Rate Base
The entity's original requested value established on which the entity is allowed to earn a particular rate of return on gas operations for 2010, filed with the Minnesota Public Utilities Commission.
Entity's original requested rate base
Entitys Original Requested Equity Ratio Percent
The ratio of equity to total capitalization (debt plus equity) used in the entity's original requested gas rate regulatory proceeding for 2010, filed with the Minnesota Public Utilities Commission.
Entity's original requested equity ratio percent (in hundredths)
Entitys Original Requested Percent Return On Equity
Rate of return on equity that the entity's original revenue increase requested represented through a gas rate case proceeding for 2010, filed with the Minnesota Public Utilities Commission.
Entity's original requested percent return on equity (in hundredths)
Entitys Original Requested Rate Increase Decrease
The entity's original requested amount of increase (decrease) to existing gas rates for 2010, filed with the Minnesota Public Utilities Commission.
Entity's original requested rate increase (decrease)
Minnesota Gas Rate Case Abstract
NSP-Minnesota Gas Rate Case
Minnesota Public Utilities Commission Abstract
Minnesota Public Utilities Commission (MPUC)
Reconciliation Of Ferc Wholesale Electric Rate Case Text Block
Reconciliation of the initial request to the settled amount in the FERC wholesale electric rate case.
Reconciliation Of FERC Wholesale Electric Rate Case
Summary Of Retail Base Rate Case Text Block
Summary of the key terms in the retail base rate case.
Summary of Retail Base Rate Case
Summary Of Renewable Energy Credit Sharing Settlement Text Block
Summary of the settlement terms of the Renewable Energy Credit (REC) sharing settlement.
Summary of Renewable Energy Credit (REC) Sharing Settlement
Major Cost Components Of2010 Electric Rate Case Reopener Text Block
Major cost components of the requested increase related to the 2010 electric rate case reopener.
Major Cost Components of the 2010 Electric Rate Case Reopener
Rate Matters Text Block
Describes all of the specific events that have or may impact rates and amortization of regulatory assets and liabilities (for example, pending or recently concluded regulatory proceedings, environmental requirements). Specifics may include quantifications related to rates, costs, and earnings. Events may relate to rate moratoriums or price tags.
Rate Matters
Letters Of Credit Outstanding
Amount of letters of credit outstanding, generally with terms of one year, to provide financial guarantees for certain operating obligations.
Letters of credit outstanding
Cap On Indemnification Provision To Lubbock
SPS has provided indemnification to Lubbock for losses arising out of any breach of the representations, warranties and covenants under the related asset purchase agreement and for losses arising out of certain other matters, including pre-closing unknown liabilities.
Cap on indemnification provision to Lubbock
Indemnification Amount To Insurance Company For Surety Bonds
Xcel Energy agreed to indemnify an insurance company in connection with surety bonds they may issue or have issued for Utility Engineering up to $80 million.
Amount of indemnification to an insurance company in connection with surety bonds issued for Utility Engineering
Guarantee Obligations Guarantor
The legal entity responsible for providing the guarantee.
Guarantor
Guarantee Performance And Payment Of Surety Bonds For Itself And Its Subsidiaries Member
Guarantee performance and payment of surety bonds for itself and Its subsidiaries by Xcel Energy.
Guarantee Performance and Payment of Surety Bonds for Itself and Its Subsidiaries [Member]
Combination Of Guarantees Benefiting Various Xcel Energy Subsidiaries Member
Combination of guarantees benefiting various Xcel Energy subsidiaries by Xcel Energy.
Combination of Guarantees Benefiting Various Xcel Energy Subsidiaries [Member]
Guarantee Of Consumer Loans For Farm Rewiring Program Member
Guarantee of consumer loans for the Farm Rewiring Program by NSP-Wisconsin.
Guarantee of Consumer Loans for the Farm Rewiring Program [Member]
Guarantee Indemnification Obligations Of Seren Under Asset Purchase Agreement2 Member
Guarantee the indemnification obligations of Seren under an Asset Purchase Agreement by Xcel Energy.
Guarantee the Indemnification Obligations of Seren Under an Asset Purchase Agreement 2 [Member]
Guarantee Indemnification Obligations Of Seren Under Asset Purchase Agreement1 Member
Guarantee the indemnification obligations of Seren under an Asset Purchase Agreement by Xcel Energy.
Guarantee the Indemnification Obligations of Seren Under an Asset Purchase Agreement 1 [Member]
Guarantee Indemnification Obligations Of Xcel Energy Argentina Inc. Under Stock Purchase Agreement Member
Guarantee the indemnification obligations of Xcel Energy Argentina Inc. under a Stock Purchase Agreement by Xcel Energy.
Guarantee the Indemnification Obligations of Xcel Energy Argentina Inc. Under a Stock Purchase Agreement [Member]
Guarantee Indemnification Obligations Of Xcel Energy Wholesale Group Inc Under Stock Purchase Agreement Member
Guarantee the indemnification obligations of Xcel Energy Wholesale Group Inc. under a Stock Purchase Agreement by Xcel Energy.
Guarantee the Indemnification Obligations of Xcel Energy Wholesale Group Inc. Under a Stock Purchase Agreement [Member]
Guarantee Indemnification Obligations Of Lubbock Under Asset Purchase Agreement Member
Guarantee the indemnification obligations of Lubbock under an Asset Purchase Agreement by SPS.
Guarantee the Indemnification Obligations of Lubbock Under an Asset Purchase Agreement [Member]
Long Term Debt Including Current Portion Fair Value Disclosure
This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure, or in the footnote disclosures. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the aggregate carrying amount of long-term borrowings as of the balance sheet date, including current and noncurrent portions.
Long-term debt, including current portion
Other Investments Fair Value Disclosure
This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure, or in the footnote disclosures. The element may be used in both the balance sheet and disclosure in the same submission. This item represents other noncurrent investments not otherwise specified in the taxonomy, not including investments in marketable securities.
Other investments
Nuclear Decommissioning Fund Fair Value Disclosure
This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption, parenthetical disclosure, or in the footnote disclosures. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the investment fund to cover the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations.
Nuclear decommissioning fund
Fair Value Assets And Liabilities Measured On Recurring Basis Transfers Line Items
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Transfers occurring between Level 2 and Level 3 for derivatives not designated as cash flow hedges
Noncurrent Liabilities Member
This element represents the balance sheet items included in noncurrent liabilities.
Noncurrent Liabilities
Current Liabilities Member
This element represents the balance sheet items included in current liabilities.
Current Liabilities
Noncurrent Assets Member
This element represents the balance sheet items included in noncurrent assets.
Noncurrent Assets
Current Assets Member
This element represents the balance sheet items included in current assets.
Current Assets
Fair Value Assets And Liabilities Measured On Recurring Basis Transfers
Summarization of information concerning assets and liabilities which are measured at fair value on a recurring basis and transferred between Level 2 and Level 3 measurements.
Fair Value Assets and Liabilities Measured on Recurring Basis Transfers
Unrealized Gain Loss On Derivatives And Commodity Contracts Included In Earnings In Fair Value Measurement With Unobservable Input Reconciliation
This element represents the aggregate increase (decrease) in the market value of open derivatives, commodity, or energy contracts. These gains (losses) are included in earnings in the reconciliation of assets and liabilities with unobservable inputs measured on a recurring basis.
Unrealized gains (losses) on Level 3 commodity derivatives, net included in earnings
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Net Asset Liability Gain Loss Recognized As Regulatory Assets And Liabilities
This element represents total gains or losses for the period (realized and unrealized), arising from net assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are recognized in regulatory assets and liabilities.
Gains recognized as regulatory assets and liabilities
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Net Asset Liability Gain Loss Included In Earnings
This element represents total gains or (losses) for the period (realized and unrealized), arising from net assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.
Losses recognized in earnings
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Transfers Net
This element represents net transfers in to and out of assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.
Transfers (out of) into Level 3
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Net Asset Liability Purchases Sales Issuances Settlements
This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to net assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).
Purchases and settlements, net
Fair Value Measurement With Unobservable Inputs Reconciliation Roll Forward
Fair value measurement with unobservable inputs, reconciliation [Rollforward]
Fair Value Measurement With Unobservable Inputs Reconciliation Line Items
Fair Value Measurement with Unobservable Inputs, Reconciliation [Line Items]
Nuclear Decommissioning Fund Member
Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations.
Nuclear Decommissioning Fund [Member]
Fair Value By Investment Type Domain
This element represents the classifications of the entity's assets and liabilities that are measured at fair value.
Fair Value, by Investment Type [Domain]
Fair Value By Investment Type Axis
This element represents a grouping of concepts that are measured at fair value.
Fair Value, by Investment Type [Axis]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Table
Summarization of information required and determined to be provided for purposes of reconciling beginning and ending balances of fair value measurements of assets and liabilities using significant unobservable inputs (Level 3). Such reconciliation, separately presenting changes during the period, at a minimum, may include: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (net); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs).
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table]
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Net Transfers Out
This element represents the net transfers out of current and noncurrent assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) to Level 2 which have taken place during the period.
Total
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Noncurrent Liabilities Transfers Out
This element represents transfers out of noncurrent liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) to Level 2 which have taken place during the period.
Noncurrent liabilities
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Current Liabilities Transfers Out
This element represents transfers out of current liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) to Level 2 which have taken place during the period.
Current liabilities
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Noncurrent Assets Transfers Out
This element represents transfers out of noncurrent assets measured at fair value on a recurring basis using unobservable inputs (Level 3) to Level 2 which have taken place during the period.
Noncurrent assets
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Current Assets Transfers Out
This element represents transfers out of current assets measured at fair value on a recurring basis using unobservable inputs (Level 3) to Level 2 which have taken place during the period.
Current assets
Trading Commodity Derivatives Not Designated As Cash Flow Hedges Abstract
Trading commodity derivatives not designated as cash flow hedges: [Abstract]
Fair Value Liabilities Measured On Recurring Basis Purchased Power Agreements Noncurrent
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Purchased power agreements
Fair Value Liabilities Measured On Recurring Basis Natural Gas Commodity Noncurrent
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Natural gas commodity
Fair Value Liabilities Measured On Recurring Basis Trading Commodity Noncurrent
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Trading commodity
Fair Value Liabilities Measured On Recurring Basis Other Derivative Instruments Noncurrent Abstract
Other derivative instruments: [Abstract]
Fair Value Liabilities Measured On Recurring Basis Derivative Liabilities Noncurrent Abstract
Noncurrent derivative liabilities [Abstract]
Fair Value Liabilities Measured On Recurring Basis Purchased Power Agreement Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Purchased power agreements
Fair Value Liabilities Measured On Recurring Basis Other Commodity Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Other commodity
Fair Value Liabilities Measured On Recurring Basis Natural Gas Commodity Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Natural gas commodity
Fair Value Liabilities Measured On Recurring Basis Electric Commodity Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Electric commodity
Fair Value Liabilities Measured On Recurring Basis Trading Commodity Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Trading commodity
Fair Value Liabilities Measured On Recurring Basis Other Derivative Instruments Current Abstract
Other derivative instruments: [Abstract]
Fair Value Liabilities Measured On Recurring Basis Vehicle Fuel And Other Commodity Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Vehicle fuel and other commodity
Fair Value Liabilities Measured On Recurring Basis Derivatives Designated As Cash Flow Hedges Current Abstract
Derivatives designated as cash flow hedges: [Abstract]
Fair Value Liabilities Measured On Recurring Basis Derivative Liabilities Current Abstract
Current derivative liabilities [Abstract]
Fair Value Assets Measured On Recurring Basis Total
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Total
Fair Value Assets Measured On Recurring Basis Equity Securities
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Equity securities (Common Stock)
Fair Value Assets Measured On Recurring Basis Mortgage Backed Securities
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Mortgage-backed securities
Fair Value Assets Measured On Recurring Basis Asset Backed Securities
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Asset-backed securities
Fair Value Assets Measured On Recurring Basis Municipal Bonds
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Municipal bonds
Fair Value Assets Measured On Recurring Basis Foreign Securities
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Foreign securities
Fair Value Assets Measured On Recurring Basis Us Corporate Bonds
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
U.S. corporate bonds
Fair Value Assets Measured On Recurring Basis Government Securities
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Government securities
Fair Value Assets Measured On Recurring Basis Debt Securities Abstract
Debt securities: [Abstract]
Fair Value Assets Measured On Recurring Basis International Equity Funds
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
International equity funds
Fair Value Assets Measured On Recurring Basis Commingled Funds
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Commingled funds
Fair Value Assets Measured On Recurring Basis Nuclear Decommissioning Fund Cash Equivalents
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Cash equivalents
Fair Value Assets Measured On Recurring Basis Nuclear Decommissioning Fund Abstract
Nuclear decommissioning fund [Abstract]
Fair Value Assets Measured On Recurring Basis Other Abstract
Other recurring fair value assets [Abstract]
Fair Value Assets Measured On Recurring Basis Purchased Power Agreements Noncurrent
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Purchased power agreements
Fair Value Assets Measured On Recurring Basis Natural Gas Commodity Noncurrent
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Natural gas commodity
Fair Value Assets Measured On Recurring Basis Trading Commodity Noncurrent
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Trading commodity
Fair Value Assets Measured On Recurring Basis Other Derivative Instruments Noncurrent Abstract
Other derivative instruments: [Abstract]
Fair Value Assets Measured On Recurring Basis Vehicle Fuel And Other Commodity Noncurrent
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Vehicle fuel and other commodity
Fair Value Assets Measured On Recurring Basis Derivatives Designated As Cash Flow Hedges Noncurrent Abstract
Derivatives designated as cash flow hedges [Abstract]
Fair Value Assets Measured On Recurring Basis Derivative Assets Noncurrent Abstract
Noncurrent derivative assets [Abstract]
Fair Value Assets Measured On Recurring Basis Purchased Power Agreements Current
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Purchased power agreements
Fair Value Assets Measured On Recurring Basis Natural Gas Commodity Current
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Natural gas commodity
Fair Value Assets Measured On Recurring Basis Electric Commodity Current
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Electric commodity
Fair Value Assets Measured On Recurring Basis Trading Commodity Current
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Trading commodity
Fair Value Assets Measured On Recurring Basis Other Derivative Instruments Current Abstract
Other derivative instruments [Abstract]
Fair Value Assets Measured On Recurring Basis Vehicle Fuel And Other Commodity Current
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Vehicle fuel and other commodity
Fair Value Assets Measured On Recurring Basis Derivatives Designated As Cash Flow Hedges Current Abstract
Derivatives designated as cash flow hedges: [Abstract]
Fair Value Assets Measured On Recurring Basis Derivative Assets Current Abstract
Current derivative assets [Abstract]
Counterparty Netting Member
The netting of receivables and payables for derivatives, and related collateral amounts, when a legally enforceable master netting agreement which is offset against the fair value measurement.
Counterparty Netting [Member]
Fair Value Inputs Total Member
This element represents the total of financial instruments at fair value, before consideration of the impact of counterparty netting.
Fair Value Total [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Disclosure Items Domain
This element represents a number of concepts which are required or desirable disclosure items concerning assets and liabilities, including financial instruments that are classified in stockholders' equity, which are measured at fair value on a recurring basis.
Fair Value, Assets and Liabilities Measured on Recurring Basis, Disclosure Items [Domain]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Disclosure Items
Fair Value Assets And Liabilities Measured On Recurring Basis Disclosure Items Axis
This element represents a number of concepts which are required or desirable disclosure items concerning assets and liabilities, including financial instruments that are classified in stockholders' equity, which are measured at fair value on a recurring basis.
Fair Value, Assets and Liabilities Measured on Recurring Basis, Disclosure Items [Axis]
Fair Value Assets And Liabilities Measured On Recurring Basis Table
Summarization of information required and determined to be disclosed concerning assets and liabilities, including financial instruments that are classified in stockholders' equity, which are measured at fair value on a recurring basis.
Fair Value, Assets and Liabilities Measured on Recurring Basis [Table]
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease Derivatives Qualifying As Hedges Roll Forward
Financial Impact of Qualifying Cash Flow Hedges: [Rollforward]
Vehicle Fuel Commodity Member
Derivative instrument whose primary underlying risk is tied to vehicle fuel commodity prices.
Vehicle Fuel Commodity Derivatives (Gallons)
Natural Gas Commodity Member
Derivative instrument whose primary underlying risk is tied to natural gas commodity prices.
Natural Gas Commodity Derivatives (MMBtu)
Natural Gas Commodity [Member]
Electric Commodity Member
Derivative instrument whose primary underlying risk is tied to electric commodity prices.
Electric Commodity Derivatives (MWh)
Electric Commodity [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Text Block
This element represents, for the fair value measurement of assets and liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (net); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs).
Changes in Level 3 Recurring Fair Value Measurements
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Transfers Between Levels Text Block
This element represents transfers in and transfers out of Levels 1, 2 and 3 due to changes in the observability of significant inputs, which are recognized as of the beginning of each period.
Transfers That Occurred Between Levels
Fair Value Assets And Liabilities Measured On Recurring Basis Text Block
This element represents the disclosure related to assets and liabilities, including financial instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).
Recurring Fair Value Measurements
Schedule Of Cash Flow Derivative Instruments In Accumulated Other Comprehensive Income Text Block
Schedule of the activity in accumulated other comprehensive income related to cash flow hedges.
Financial Impact of Qualifying Cash Flow Hedges
Summary Of Derivative Instruments Notional Amounts Text Block
Disclosure of the notional amounts of derivative instruments entered into by the entity as of the balance sheet date.
Derivative Instruments Notional Amounts
Derivative Instruments And Fair Value Measurements Disclosure Text Block
This element can be used to disclose the entity's entire derivative instruments and hedging activities and fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities.
Derivative Instruments and Fair Value Measurements
Component Of Other Income Expense Nonoperating Line Items
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Other Income, Net [Line Items]
Insurance Policy Expenses Member
This element represents insurance policy expenses.
Insurance Policy (Expenses) Income [Member]
Coli Settlement Member
Settlement agreement with Provident related to all claims asserted by Xcel Energy, PSCo and PSRI against Provident in a lawsuit associated with the discontinued COLI program.
COLI Settlement [Member]
Component Of Other Income Expense Nonoperating Name Domain
Name of each detailed component of other nonoperating income or expense.
Component of Other Income Expense Nonoperating, Name [Domain]
Component Of Other Income Expense Nonoperating Axis
Group that contains each detailed component of other nonoperating income or expense.
Component of Other Income Expense Nonoperating [Axis]
Other Income Expense Net Table
Provides a description and amount of each detailed component of other nonoperating income or expense, which has been presented on the income statement.
Other Income Expense Net [Table]
Schedule Of Nonoperating Income Expense Text Block
A schedule of the components of other nonoperating income, net of other nonoperating expenses.
Other income, net
Nonoperating Income Expense Disclosure Text Block
Discloses nonoperating income and expense items.
Other Income, Net
Net Projected Postretirement Health Care Benefit Payments In Five Fiscal Years Thereafter
The net amount of postretirement health care benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).
2016-2020
Net Projected Postretirement Health Care Benefit Payments In Year Five
The net amount of postretirement health care benefits expected to be paid in Year 5.
2015
Net Projected Postretirement Health Care Benefit Payments In Year Four
The net amount of postretirement health care benefits expected to be paid in Year 4.
2014
Net Projected Postretirement Health Care Benefit Payments In Year Three
The net amount of postretirement health care benefits expected to be paid in Year 3.
2013
Net Projected Postretirement Health Care Benefit Payments In Year Two
The net amount of postretirement health care benefits expected to be paid in Year 2.
2012
Net Projected Postretirement Health Care Benefit Payments In Year One
The net amount of postretirement health care benefits expected to be paid in Year 1.
2011
Net Projected Postretirement Health Care Benefit Payments Abstract
Net Projected Postretirement Health Care Benefit Payments [Abstract]
Gross Projected Postretirement Health Care Benefit Payments In Five Fiscal Years Thereafter
The amount of the gross postretirement health care benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).
2016-2020
Gross Projected Postretirement Health Care Benefit Payments In Year Five
The amount of the gross postretirement health care benefits expected to be paid in Year 5.
2015
Gross Projected Postretirement Health Care Benefit Payments In Year Four
The amount of the gross postretirement health care benefits expected to be paid in Year 4.
2014
Gross Projected Postretirement Health Care Benefit Payments In Year Three
The amount of the gross postretirement health care benefits expected to be paid in Year 3.
2013
Gross Projected Postretirement Health Care Benefit Payments In Year Two
The amount of the gross postretirement health care benefits expected to be paid in Year 2.
2012
Gross Projected Postretirement Health Care Benefit Payments In Year One
The amount of the gross postretirement health care benefits expected to be paid in Year 1.
2011
Gross Projected Postretirement Health Care Benefit Payments Abstract
Gross projected postretirement health care benefit payments [Abstract]
Defined Benefit Plan Time Period From Current Period That Rate Reaches Ultimate Trend Rate
The time period (in years) until the ultimate health care cost trend rate is expected to be reached.
Period until ultimate trend rate is reached (in years)
Defined Benefit Plan Health Care Cost Trend Rate Revised
The revised assumed medical trend rate used to measure the expected cost of benefits covered by the plan (gross eligible charges).
Revised medical trend assumption rate (in hundredths)
Defined Benefit Plan Health Care Cost Trend Rate Initial
The initial assumed medical trend rate used to measure the expected cost of benefits covered by the plan (gross eligible charges).
Initial medical trend assumption rate (in hundredths)
Straight Line Amortization Period For Unrecognized Accumulated Postretirement Benefit Obligation
The straight-line amortization period (in years) for unrecognized accumulated postretirement benefit obligation due to the adoption of accounting guidance regarding other non-pension postretirement benefits.
Straight-line amortization period for unrecognized accumulated postretirement benefit obligation (in years)
Postretirement Health Care Benefits Abstract
Postretirement Health Care Benefits [Abstract]
Fair Market Value Adjustment Rate To Reflect Investment Gains And Losses
The rate per year over the last five years in which the fair market value of assets is adjusted to reflect investment gains and losses in order to determine the market-related value of pension assets.
Rate per year in which fair market value of assets is adjusted to reflect investment gains and losses (in hundredths)
Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets Next Fiscal Year
An assumption as to the rate of return on plan assets for next fiscal year reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.
Expected rate of return on assets used to calculate pension cost for next fiscal year (in hundredths)
Defined Benefit Plan Additional Cost Recognized Due To Effects Of Regulation
The additional amount of costs recognized in net periodic benefit cost as reported in the financial statements of the entity due to effects of regulation.
Additional cost recognized due to effects of regulation
Net benefit cost (credit) recognized for financial reporting
Defined Benefit Plan Costs Credit Not Recognized Due To Effects Of Regulation
The amount of (costs) credit not recognized in net periodic benefit cost as reported in the financial statements of the entity due to effects of regulation.
(Costs) credit not recognized due to effects of regulation
Estimated Future Employer Contributions To Pension Plans In Next Fiscal Year Maximum
The employer's best estimate, as soon as it can be reasonably determined, of the maximum amount of contributions expected to be paid to the Company's pension plans for the next fiscal year.
Estimated pension funding contributions for next year, maximum
Estimated Future Employer Contributions To Pension Plans In Next Fiscal Yearr Minimum
The employer's best estimate, as soon as it can be reasonably determined, of the minimum amount of contributions expected to be paid to the Company's pension plans for the next fiscal year.
Estimated pension funding contributions for next year, minimum
Funded Status Percentage Overall Pension Plan
The level of funded status for overall pension plans base don current pension assumptions.
Funded status of overall pension plan (in hundredths)
Voluntary Pension Contributions To Non Bargaining Plan
The amount of cash or cash equivalents contributed by the entity to fund the NCE Non-Bargaining Pension Plan.
Voluntary contributions to NCE Non-Bargaining Pension Plan
Voluntary Contributions To Bargaining Pension Plan
The amount of cash or cash equivalents contributed by the entity to fund the PSCo Bargaining Pension Plan.
Voluntary contributions to PSCo Bargaining Pension Plan
Estimated Future Employer Contributions To Pension Plans In Next Fiscal Year
The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the Company's pension plans during the next fiscal year beginning after the date of the latest statement of financial position.
Estimated contribution to Xcel Energy's pension plans in next fiscal year
Amounts Related To Funded Status Of Plans Recorded As Net Of Tax Accumulated Other Comprehensive Income
Amount related to the funded status of plans which has been recorded as net -of-tax accumulated other comprehensive income based upon the expected recovery in rates.
Net-of-tax accumulated other comprehensive income
Amounts Related To Funded Status Of Plans Recorded As Deferred Income Taxes
Amount related to the funded status of plans which has been recorded as deferred income taxes based upon the expected recovery in rates.
Deferred income taxes
Amounts Related To Funded Status Of Plans Recorded As Regulatory Liabilities
Amount related to the funded status of plans which has been recorded as regulatory liabilities refundable to customers.
Regulatory liabilities
Amounts Related To Funded Status Of Plans Recorded As Regulatory Assets
Amount related to the funded status of plans which has been recorded as regulatory assets based upon the expected recovery in rates.
Regulatory assets
Amounts Related To Funded Status Of Plans Have Been Recorded As Follows Based Upon Expected Recovery In Rates Abstract
Amounts Related to the Funded Status of Plans Have Been Recorded as Follows Based Upon Expected Recovery In Rates [Abstract]
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized And Unrealized Gain Loss
This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3).
Realized and unrealized gains (losses)
Defined Benefit Plan Assets Measured At Fair Value For Each Fair Value Hierarchy Levels Abstract
Defined Benefit Plan Assets Measured at Fair Value For Each of the Fair Value Hierarchy Levels [Abstract]
Registered Investment Companies Mutual Funds Member
An investment with a management investment company, which allows investors to pool their capital with that of other investors in order to purchase professionally-managed groups of diversified securities, primarily mutual funds.
Registered Investment Companies (Mutual Funds) [Member]
Commingled Equity And Bond Funds Member
An investment that pools funds from many investors to invest in a combination of underlying investments, primarily equity and bond investments.
Commingled Equity and Bond Funds [Member]
Defined Benefit Plan Target Allocation Percentage Of Assets Cash
Target allocation percentage of investments in cash to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.
Cash (in hundredths)
Defined Benefit Plan Target Allocation Percentage Of Assets Short To Intermediate Fixed Income Securities
Target allocation percentage of investments in short to intermediate fixed income securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.
Short-to-intermediate fixed income securities (in hundredths)
Defined Benefit Plan Target Allocation Percentage Of Assets Long Duration Fixed Income Securities
Target allocation percentage of investments in long duration fixed income securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.
Long-duration fixed income securities (in hundredths)
Assumed Average Annual Return For Pension Investments Used To Determine Pension Costs
Assumed annual investment-return for pension investments.
Assumed average annual return for pension investments used to determine pension costs (in hundredths)
Historical Weighted Average Annual Return For Portfolio Of Pension Investments
Element represents the historical weighted average annual return for the past 20 years for portfolio of pension investments.
Historical weighted average annual return for past 20 years for portfolio of pension investments (in hundredths)
Pension Benefits Abstract
Pension Benefits [Abstract]
Number Of Nuclear Operation Bargaining Employees Receiving Benefits Inder Collective Bargaining Agreements
Element represents the number of nuclear operation bargaining employees receiving benefits under several collective-bargaining agreements.
Number of nuclear operation bargaining employees receiving benefits under collective bargaining-agreements
Number Of Bargaining Employees Receiving Benefits Under Several Collective Bargaining Agreements
Element represents the number of bargaining employees receiving benefits under several collective-bargaining agreements
Number of bargaining employees receiving benefits under several collective bargaining agreements
Percent Of Employees Receiving Benefits Who Are Represented By Local Labor Unions Under Collective Bargaining Agreements
Element represents the approximate percent of employees receiving benefits who are represented by several local labor unions under several collective-bargaining agreements
Approximate percent of employees receiving benefits who are represented by local labor unions under collective bargaining agreements (in hundredths)
Employees Receiving Benefits Who Are Represented By Local Labor Unions Under Collective Bargaining Agreements Line Items
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Employees receiving benefits who are represented by several local labor unions under several collective-bargaining agreements [Line Items]
Employees Receiving Benefits Who Are Represented By Local Labor Unions Under Collective Bargaining Agreements Table
Describes the percentage, number and type of employees receiving benefits who are represented by several local labor unions under several collective-bargaining agreements.
Employees Receiving Benefits Who Are Represented by Local Labor Unions Under Collective-Bargaining Agreements [Table]
Schedule Of Expected Benefit Payments Text Block
Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.
Projected Benefit Payments for the Pension and Postretirement Benefit Plans
Components Of Net Periodic Postretirement Benefit Costs Text Block
This element represents the components of net periodic postretirement benefit costs for the reporting periods.
Components of Net Periodic Postretirement Benefit Costs and Significant Assumptions Used to Measure Costs
Effects Of 1 Percent Change In Assumed Healthcare Cost Trend Rate Text Block
This element represents the effect of a one percent change in the assumed healthcare cost trend rate.
Effects of 1-Percent Change in Assumed Health Care Cost Trend Rate
Comparison Of Actuarially Computed Benefit Obligation And Plan Assets For Xcel Energy Postretirement Health Care Plans That Benefit Employees Of Its Utility Subsidiaries Text Block
This element represents a comparison of the actuarially computed postretirement benefit obligation and plan assets, on a combined basis as of the end of the reporting period.
Comparison of Actuarially Computed Postretirement Benefit Plan Obligation and Plan Assets, on a Combined Basis
Changes In Level3 Postretirement Benefit Plan Assets Text Block
This element represents, for the fair value measurement of postretirement benefit plan assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances.
Changes in Level 3 Postretirement Benefit Plan Assets
Postretirement Benefit Plan Assets Measured At Fair Value For Each Of The Fair Value Hierarchy Levels Text Block
This element represents the disclosure related to postretirement benefit plan assets measured at fair value. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).
Postretirement Benefit Plan Assets Measured at Fair Value for each of the Fair Value Hierarchy Levels
Components Of Net Periodic Pension Cost Credit Text Block
This element represents the components of net periodic pension cost (credit) for the reporting periods.
Components of Net Periodic Cost (Credit) and Significant Assumptions Used to Measure Costs
Comparison Of Actuarially Computed Pension- Benefit Obligation And Plan Assets, On A Combined Basis Text Block
This element represents a comparison of the actuarially computed pension-benefit obligation and plan assets, on a combined basis as of the end of the reporting period.
Comparison of Actuarially Computed Pension-Benefit Obligation and Plan Assets, on a Combined Basis
Changes In Level3 Pension Plan Assets Text Block
This element represents, for the fair value measurement of pension assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances.
Changes in Level 3 Pension Plan Assets
Pension Plan Assets Measured At Fair Value For Each Fair Value Hierarchy Level Text Block
This element represents the disclosure related to pension plan assets measured at fair value. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).
Pension Plan Assets Measured at Fair Value for each of the Fair Value Hierarchy Levels
Defined Benefit Plan Target Asset Allocation Text Block
This element represents the target pension asset allocation in the Company's defined benefit pension plan as of the end of the reporting period.
Target Pension Asset Allocations
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Approved For Issuance Under2005 Executive Annual Incentive Plan
The number of shares approved for issuance under 2005 Executive Annual Incentive Plan.
Number of shares approved for issuance under 2005 Executive Annual Incentive Plan (in shares)
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Approved For Issuance Under Executive Annual Incentive Plan
The number of shares approved for issuance under the Executive Annual Incentive Plan approved in 2000.
Number of shares approved for issuance under Executive Annual Incentive Plan approved in 2000 (in shares)
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Approved For Issuance Under2005 Omnibus Incentive Plan
The number of shares of common stock approved for issuance under the Xcel Energy 2005 Omnibus Incentive Plan.
Number of shares approved for issuance under the Xcel Energy 2005 Omnibus Incentive Plan (in shares)
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Issuance Under Omnibus Incentive Plan
The maximum aggregate number of shares of common stock approved for issuance under the Xcel Energy Omnibus Incentive Plan in 2000.
Maximum aggregate number of shares of common stock available for issuance under the Xcel Energy Omnibus Incentive Plan approved in 2000 (in shares)
Employer Recognized Compensation Expense Matching Payment To Employee401 K Plan
Matching contributions related to Company's 401(k) plan included in compensation cost for share-based awards for the period.
Matching contributions related to Xcel Energy 401(k) plan included in compensation cost for share-based awards
Employee Service Share Based Compensation Cash Used To Settle Awards
Aggregate cash paid by the entity during the period to settle liability instruments granted under share-based payment arrangements.
Amount of cash used to settle PSP awards
Employee Service Share Based Compensation Cash And Stock Used To Settle Awards
Aggregate cash and stock paid by the entity during the period to settle performance awards granted under the Company's PSP Awards incentive plan.
Settlement amount (cash and common stock)
Share Based Compensation Arrangement Maximum Payout Range
The maximum payout range for participants in the Performance Share Plan Awards incentive plan based upon the company's attainments of pre-established performance ratio targets.
Maximum payout percentage (in hundredths)
Share Based Compensation Arrangement Minimum Payout Range
The minimum payout range for participants in the Performance Share Plan Awards incentive plan based upon the company's attainments of pre-established performance ratio targets.
Minimum payout percentage (in hundredths)
Number Of Shares Of Common Stock Into Which Share Based Compensation Can Be Converted
The value of stock equivalent units expressed as number of shares of common stock into which the units can be converted.
Number of shares of common stock into which the share-based compensation can be converted
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Non Vested Weighted Average Remaining Contractual Term
The weighted-average period between the balance sheet date and the date on which the share-based award will be forfeited if the performance criteria have not bee met for nonvested equity awards, which may be expressed in a decimal value for number of years.
Weighted average remaining contractual life of nonvested RSUs (in years)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Non Vested In Period Total Fair Value
The total fair value of nonvested share-based awards for which the grantee has not yet gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares in accordance with the terms of the arrangement.
Total fair value of nonvested RSUs
Share Based Compensation Arrangement By Share Based Payment Award Rsu Forfeiture Period
Number of years after grant date in which restricted stock units will be forfeited if performance criteria has not been met (for example, in years, month and year).
Number of years after grant date in which RSUs will be forfeited if performance criteria has not been met (in years)
Share Based Compensation Arrangement By Share Based Payment Award Restrictions On Rsus Will Not Lapse Period
Number of years after grant date in which restrictions on restricted stock units will lapse if performance criteria has been met (for example, in years, month and year).
Number of years after grant date in which restrictions on RSUs will not lapse, even if performance goals have been achieved (in years)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Dividend Equivalent In Period Weighted Average Grant Date Fair Value
The weighted average fair value as of grant dates pertaining to a share-based award plan other than a stock option plan for dividend equivalents on shares outstanding during the period in accordance with the terms of the arrangement.
Dividend equivalent, weighted average grant date fair value (in dollars per share)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Distributed In Period Weighted Average Grant Date Fair Value
The weighted average fair value as of grant dates pertaining to a share-based award plan other than a stock option plan for units that do not need to vest and are readily available, regardless of in stock equivalents or in cash, during the period in accordance with the terms of the arrangement.
Units distributed, weighted average grant date fair value (in dollars per share)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Settled In Period
The number of units/shares settled under a share-based award plan during the period in cash or stock.
Awards settled (in shares)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Dividend Equivalents In Period
The number of shares issuable under a share-based award plan pertaining to dividend equivalents on shares outstanding during the period on other than stock option plans.
Dividend equivalents (in shares)
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Distributed In Period
The number of units under a share-based award plan other than a stock option plan that do not need to vest and are readily available, regardless of in stock equivalents or in cash, during the period in accordance with the terms of the arrangement.
Units distributed (in shares)
Psp Awards Member
Share-based compensation awarded to certain employees but not transferable until specific performance requirements are met. These awards are paid in the form of stock.
PSP Awards [Member]
Stock Equivalent Units Member
Share-based compensation awarded to non-employee members of the Board of Directors, payable upon termination of service in either the form of stock or the cash equivalent.
Stock Equivalent Unit Plan [Member]
Restricted Stock Units Member
Share-based compensation awarded to employees but not transferable until specific performance requirements are met. These awards are paid in either the form of stock.
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Market Value
Market value of stock options exercised during the period.
Market value of exercises
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range3 Member
This element represents exercise price range 3 of shares authorized and outstanding at the end of period.
Exercise Price Range 3 [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range2 Member
This element represents exercise price range 2 of shares authorized and outstanding at the end of period.
Exercise Price Range 2 [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range1 Member
This element represents exercise price range 1 of shares authorized and outstanding at the end of period.
Exercise Price Range 1 [Member]
Share Based Compensation Arrangement By Share Based Payment Award Stock Option Award Effective Term
Period of time that stock options are still effective.
Normal term of options
Psp Awards Text Block
Disclosure of Performance Share Plan awards granted and the total amounts of performance awards settled during the period.
PSP Awards
Stock Equivalent Unit Plan Text Block
Disclosure of granted stock equivalent units and a summary of the changes in the quantity and weighted average grant date fair value for the period.
Stock Equivalent Unit Plan
Restricted Stock Units Text Block
Disclosure of granted restricted stock units and a summary of the changes in the quantity and weighted average grant date fair value for the period.
Restricted Stock Units
Restricted Stock Text Block
Disclosure of granted shares of restricted stock and a summary of the changes in the quantity and weighted average grant date fair value for the period.
Restricted Stock
Cash Received And Actual Tax Benefit For Tax Deductions From Stock Options Exercised Text Block
Disclosure of cash received and actual tax benefit for tax deductions from stock options exercised
Cash Received and Actual Tax Benefit from Exercised Stock Options
Disclosure Of Share Based Compensation Arrangements By Share Based Payment Award Options Exercised Text Block
Disclosure related to the market value and intrinsic value of exercised stock options that have been awarded as share-based compensation to employees.
Total Market Value and Total Intrinsic Value of Stock Options Exercised
Maximum Amount Subsidiary Can Borrow From Specific Subsidiary
Maximum amount one entity can borrow from a designated related entity.
Maximum amount NSP-Wisconsin can borrow only from NSP-Minnesota
Ferc Authorized Participation Amount In Intra System Financing Money Pool
Maximum participation in certain intra-system financings involving holding companies granted under the Federal Energy Regulatory Commission blanket authorization.
FERC authorized participation amount in intra-system financing money pool
Maximum Total Capitalization
The maximum total capitalization allowed for the entity.
Maximum total capitalization for NSP-Minnesota
Percentage Of Total Capitalization Short Term Debt Cannot Exceed
The maximum percentage short-term debt cannot exceed total capitalization in order to further issue short-term debt.
Percentage of total capitalization short-term debt cannot exceed (in hundredths)
Equity To Total Capitalization Ratio Higher Range
The minimum ratio of equity to net capital required to be maintained by the entity to engage in issuance of long-term debt securities.
Equity-to-total capitalization ratio, higher range (in hundredths)
Equity To Total Capitalization Ratio Lower Range
The minimum ratio of equity to net capital required to be maintained by the entity to engage in issuance of long-term debt securities.
Equity-to-total capitalization ratio, lower range (in hundredths)
Maximum Short Term Debt Authorized For Issuance
Maximum amount of short-term debt the entity is authorized to issue, subject to the jurisdiction of they applicable state regulatory commissions and/or the Federal Energy Regulatory Commission under the Federal Power Act.
Maximum short-term debt authorized for issuance
Maximum Long Term Debt Authorized For Issuance
Maximum amount of long-term debt the entity is authorized to issue, subject to the jurisdiction of the applicable state regulatory commissions and/or the Federal Energy Regulatory Commission under the Federal Power Act.
Maximum long-term debt authorized for issuance
Short And Long Term Debt Disclosure Abstract
Short-Term and Long-Term Debt Disclosure [Abstract]
Short And Long Term Debt Disclosure Line Items
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
Short-Term and Long-Term Debt Disclosure [Line Items]
Schedule Of Short And Long Term Debt Authorized Issuance Disclosures Table
A table or schedule providing information pertaining to regulatory authorized amounts available for the issuance of securities.
Schedule of Short-Term and Long-Term debt [Table]
Additional Cash Dividends On Common Stock Which Could Have Been Paid Per First Mortgage Indenture
Additional cash dividends on common stock which the entity's subsidiary could have paid to the entity based on certain restrictions contained in the subsidiary's first mortgage indenture.
Additional cash dividends on common stock which could have been paid per NSP-Minnesota's first mortgage indenture
Capitalization Ratio
Capitalization ratio is equal to (i) common stock plus surplus divided by (ii) the sum of common stock plus surplus plus long-term debt.
Capitalization ratio (in hundredths)
Minimum Capitalization Ratio For Dividend Payments Restriction
Minimum capitalization ratio which is equal to (i) common stock plus surplus divided by (ii) the sum of common stock plus surplus plus long-term debt, before restrictions are placed on entity's right to pay dividends on common stock.
Minimum capitalization ratio for dividend payments restriction (in hundredths)
Dividend And Other Capital Related Restrictions Abstract
Dividend and Other Capital-Related Restrictions [Abstract]
Common Stock Dividends Declared Per Share Abstract
Common stock dividends declared per share [Abstract]
Dilutive Impact Of Common Stock Equivalents On Earnings Per Share Abstract
Dilutive Impact of Common Stock Equivalents on Earnings per Share [Abstract]
Common Stock Commission Fee For Shares Re Offered To Public
Commission per share of common stock to be paid by purchaser of common stock.
Commission fees per share of common stock to the underwriters (in dollars per share)
Common Stock Re Offered Share Issue Price To Public
Price per share of common stock offered to public.
Offering price of common stock to the public (in dollars per share)
Common Stock New Share Issue Price To Underwriters
Price per share of common stock issued to underwriters of new issuance.
Offering price of common stock to underwriters (in dollars per share)
Forward Contract Indexed To Issuers Equity Underwriting Fees Per Share
The cost of underwriting fees on a per share basis.
Underwriting fees per share of common stock in public offering
Forward Contract Indexed To Issuers Equity Offering Price
The offering price of the entity's stock, before underwriting fees
Offering price of common stock in public offering, before underwriting fees
Forward Contract Indexed To Issuers Equity Initial Pricing
The offering price of the entity's common stock in public offering, net of underwriting fees.
Initial pricing of equity forward instruments based on the common stock offering price, net of underwriting fees
Forward Contract Indexed To Issuers Equity Spread
A spread percentage deducted from the federal funds rate used to calculate the cash proceeds due to the company at physical settlement of equity forward instruments.
Spread used to calculate proceeds at physical settlement of equity forward instruments (in hundredths)
Forward Contract Indexed To Issuers Equity Cash Settlement Amount Physical Delivery
The amount of cash proceeds from physically settling the equity forward instruments.
Cash proceeds from settling forward agreements
Forward Contract Indexed To Issuers Equity Over Allotment Shares
The number of instruments issued to a banking counterparty consistent with the over allotted shares from the public offering.
Over allotment of instruments issued to banking counterparty
Forward Contract Indexed To Issuers Equity Shares Issued To Banking Counterparty
The total number of shares of common stock issued to a banking counterparty.
Total number of shares of common stock issued to banking counterparty
Number Of Quarterly Dividends In Arrears On Preferred Stock Entitle Holders To Elect Majority Of Board Of Directors
The minimum number of quarterly dividends payable in arrears that allows for the holders, voting as a class, to elect the smallest number of directors necessary to constitute a majority of the Board of Directors.
Number of quarterly dividends in arrears of any series of preferred stock that allows for election of majority of Board of Directors
Number Of Votes Holders Of Other Series Preferred Stock Are Entitled To Per Each Share Held
The number of votes holders of the other than $3.60 series of redeemable preferred stock are entitled to per each share held.
Number of votes holders of all other series of preferred stock are entitled to per each share held
Number Of Votes Holders Of360 Series Preferred Stock Are Entitled To Per Each Share Held
The number of votes holders of the $3.60 series preferred stock are entitled to per each share held.
Number of votes holders of $3.60 series preferred stock are entitled to per each share held
Preferred Stock Redemption Price Per Share Higher Range
The maximum price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.
Preferred stock, redemption price, higher range (in dollars per share)
Preferred Stock Redemption Price Per Share Lower Range
The minimum price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.
Preferred stock, redemption price, lower range (in dollars per share)
Number Of Series Of Preferred Stock Outstanding
Number of series of redeemable preferred stock outstanding.
Number of series of preferred stock outstanding
Common Stock Dividends Declared Per Share Text Block
This element is used to capture the complete disclosure pertaining to an entity's dividends declared per common share on a quarterly basis.
Common Stock Dividends Declared per Share
Preferred Shares By Subsidiary Text Block
This element is used to capture an entity's preferred shares by subsidiary, including par or stated value per share, shares authorized, shares issued, shares outstanding, and other information necessary to a fair presentation.
Preferred Shares by Subsidiary
Deferred Tax Assets Other Comprehensive Income
The amount as of the balance sheet date of the estimated future tax effects arising from unrealized gain on items included in other comprehensive income which will increase future taxable income when such gain is realized.
Other comprehensive income
Deferred Tax Assets Deferred Investment Tax Credits
The tax effect as of the balance sheet date of the amount of future tax deductions arising from deferred investment tax credits.
Deferred investment tax credits
Deferred Tax Assets Environmental Remediation
The tax effect as of the balance sheet date of the amount of future tax deductions arising from environmental remediation.
Environmental remediation
Deferred Tax Assets Rate Refund
The tax effect as of the balance sheet date of the amount of future tax deductions arising from rate refunds to customers.
Rate refund
Deferred Tax Assets Regulatory Liabilities
The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from differences in accounting under GAAP and tax returns for liabilities established under GAAP pertaining to rate-setting.
Regulatory liabilities
Deferred Tax Assets Unbilled Revenue Fuel Costs
The tax effect as of the balance sheet date of the amount of the estimated future tax deductions attributable to unbilled revenue for fuel costs.
Unbilled revenue - fuel costs
Deferred Tax Liabilities Partnership Income Loss
The tax effect as of the balance sheet date of the amount of the estimated future tax deductions attributable to the difference between the tax basis and the generally accepted accounting principles basis of a company's equity method investment which will decrease future taxable income when such basis difference reverses.
Partnership income/loss
Deferred Tax Liabilities Deferred Fuel Costs
The tax effect as of the balance sheet date of the amount of the estimated future tax deductions attributable to deferred fuel costs.
Deferred fuel costs
Deferred Tax Liabilities Employee Benefits
The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from employee benefit costs not otherwise specified in the taxonomy, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.
Employee benefits
Deferred Investment Tax Credits
The component of income tax expense for the period representing the amount of the deferred investment tax credits available to reduce future taxable income under enacted tax laws.
Deferred investment tax credits
Deferred Tax Credits
The component of income tax expense for the period representing the amount of the deferred tax credits available to reduce future taxable income under enacted tax laws.
Deferred tax credits
Deferred Change In Unrecognized Tax Expense Benefit
The component of income tax expense for the period representing the deferred change in unrecognized tax expense (benefit).
Deferred change in unrecognized tax expense (benefit)
Current Change In Unrecognized Tax Expense Benefit
The component of income tax expense for the period representing the current change in unrecognized tax expense (benefit).
Current change in unrecognized tax expense (benefit)
Effective Income Tax Rate Reconciliation Change In Unrecognized Tax Benefits
The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate due to the change in unrecognized tax benefits.
Change in unrecognized tax benefits (in hundredths)
Effective Income Tax Rate Reconciliation Resolution Of Income Tax Audits And Other
The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate due to the resolution of income tax audits and other.
Resolution of income tax audits and other (in hundredths)
Effective Income Tax Rate Reconciliation Regulatory Differences Utility Plant Items
The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by regulatory differences in utility plant items.
Regulatory differences - utility plant items (in hundredths)
Effective Income Tax Rate Reconciliation Tax Credits Recognized Net Of Federal Income Tax Expense
The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by tax credits generated or utilized under enacted tax laws during the period, net of federal income tax expense.
Tax credits recognized, net of federal income tax expense (in hundredths)
Increases Decreases In Tax From Abstract
Increases (Decreases) in Tax From [Abstract]
Operating Loss And Tax Credit Carryforwards Expiration Dates
The expiration date of operating loss and tax credit carryforwards, or the applicable range of such expiration dates.
Carryforward expiration periods
Tax Credit Carryforward Valuation Allowance Net Of Federal Benefit
The portion of the deferred tax asset arising from a tax credit carryforward for which it is more likely than not that a tax benefit will not be realized.
Valuation allowances for state tax credit carryforwards, net of federal benefit
Tax Credit Carryforward Net Of Federal Detriment Amount
The amount of the tax credit carryforward, net of federal tax effects, available to reduce future taxable income under enacted tax laws.
State tax credit carryforwards, net of federal detriment
Operating Loss And Tax Credit Carryforwards By Tax Authority Axis
Pertinent information pertaining to each tax loss and tax credit carryforward, by tax authority.
Operating Loss and Tax Credit Carryforwards by Tax Authority [Axis]
Operating Loss And Tax Credit Carryforwards Table
Schedule reflecting net operating loss and tax credit carryforwards.
Operating Loss and Tax Credit Carryforwards [Table]
Unrecognized Tax Benefits Interest Expense Discontinued Operations
This element represents interest income (expense) from discontinued operations recognized during the reporting period for unrecognized tax benefits computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.
Interest income (expense) related to unrecognized tax benefits - discontinued operations
Unrecognized Tax Benefits Interest Expense Continuing Operations
This element represents interest income (expense) from continuing operations recognized during the reporting period for unrecognized tax benefits computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.
Interest income (expense) related to unrecognized tax benefits - continuing operations
Interest Payable Related To Unrecognized Tax Benefits Reported In Continuing Operations Roll Forward
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
Interest Payable Related to Unrecognized Tax Benefits [Roll Forward]
Unrecognized Tax Benefits Period Increase Decrease Continuing Operations
The net amount of all increases and decreases in unrecognized tax benefits.
Net increase (decrease) of unrecognized tax benefits
Tax Benefits Associated With Net Operating Loss Carryforward Related To Unrecognized Tax Benefits
Tax benefits associated with NOL and tax credit carryforwards related to unrecognized tax benefits.
Tax benefits associated with NOL and tax credit carryforwards related to unrecognized tax benefits
Reduction Of Unrecognized Tax Benefits Associated With Nol And Tax Credit Carryforwards Abstract
Reduction of Unrecognized Tax Benefits Associated with NOL and Tax Credit Carryforwards [Abstract]
Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions Discontinued Operations
The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns for discontinued operations, excluding amounts pertaining to examined tax returns.
Reductions for tax positions of prior years - discontinued operations
Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions Continuing Operations
The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns for continuing operations, excluding amounts pertaining to examined tax returns.
Reductions for tax positions of prior years - continuing operations
Unrecognized Tax Benefits That Would Not Impact Effective Tax Rate
The total amount of unrecognized tax benefits for which the ultimate deductibility is highly certain but for which there is uncertainty about the timing of such deductibility and, if recognized, would not affect the effective tax rate but would accelerate the payment of cash to the taxing authority to an earlier period.
Unrecognized tax benefit - Temporary tax positions
Unrecognized Tax Benefit Abstract
Permanent and Temporary Tax Positions in Unrecognized Tax Benefits [Abstract]
Income Tax Examination Earliest Open Year Subject To Examination
The earliest open tax year subject to income tax examination by a taxing authority.
Earliest year subject to examination
Wisconsin Member
The tax department of Wisconsin entitled to levy and collect income taxes from the entity.
Wisconsin [Member]
Texas Member
The tax department of Texas entitled to levy and collect income taxes from the entity.
Texas [Member]
Minnesota Member
The tax department of Minnesota entitled to levy and collect income taxes from the entity.
Minnesota [Member]
Colorado Member
The tax department of Colorado entitled to levy and collect income taxes from the entity.
Colorado [Member]
Income Tax Rate Reconciliation Estimated Additional Tax Expense Current Year
Additional tax expense associated with current year retiree health care accruals.
Additional tax expense associated with current year retiree health care accruals
Income Tax Reconciliation Deductions Medicare Prescription Drug Benefit Subsidy Reversal
The amount of previously recognized tax benefits relating to Medicare Part D subsidies that were reversed during the period.
Previously recorded tax benefits reversed
Medicare Part D Subsidy Reimbursements Abstract
Medicare Part D Subsidy Reimbursements [Abstract]
Reduction To Expense Due To Agreement On Applicable Interest Netting Computations
Reduction in expense resulting from an agreement with the taxing authority on applicable interest netting computations.
Reduction to expense due to agreement on applicable interest netting computations
Interest Expense Net Of Tax
This element represents the interest expense included in the adjustment related to a non-recurring matter, net of tax.
Interest expense on tax review adjustment, net of tax
Tax Adjustment And Interest Unusual Items
The total of tax expense and interest expense related to a non-recurring adjustment.
Net non-recurring adjustment recorded by PSRI
Income Tax Reconciliation Tax Interest And Penalty Adjustment
Reflects the tax, interest and penalty expense for significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement, etc.
Settlement of the U.S. government's claims for tax, penalty, and interest related to COLI program
Coli Abstract
Corporate Owned Life Insurance [Abstract]
Components Of Net Deferred Tax Liability From Continuing Operations Text Block
Disclosure of the significant components of the temporary differences comprising deferred tax assets and liabilities.
Components of Net Deferred Tax Liability from Continuing Operations
Components Of Income Tax Expense Benefit From Continuing Operations Text Block
Disclosure of income tax expense (benefit) from continuing operations. Includes both current and deferred federal tax expense (benefit).
Components of Income Tax Expense from Continuing Operations
Reconciliation Of Effective Rate Of Income Tax Expense Benefit Continuing Operations Income Tax Text Block
Reconciliation between the effective rate of the actual provision for income taxes on continuing operations and that computed by applying the US statutory rate to income from continuing operations before income taxes.
Reconciliation of Effective Tax Rate from Continuing Operations
Nol And Tax Credit Carryforwards Text Block
Disclosure of net operating loss and tax credit carryforwards.
NOL and Tax Credit Carryforwards
Transmission And Other Facilities Including Substations Member
Various transmission lines and substations co-owned by PSCo and other entities.
Transmission and Other Facilities, including Substations [Member]
Comanche Unit 3 Member
Comanche is a coal-fired, steam-electric generating station. Unit 3 is a 850 megawatt plant.
Comanche Unit 3 [Member]
Craig Common Facilities Units 1 2 and 3 Member
Supporting Craig Units 1 and 2 are commonly used facilities not specific to any unit.
Craig Common Facilities 1, 2 and 3 [Member]
Craig Units 1 And 2 Member
Craig Station is a coal-fired, steam electric generating station with three operating units. Units 1 and 2 are 428 megawatt plants.
Craig Units 1 and 2 [Member]
Hayden Common Facilities Member
Supporting Hayden Units 1 and 2 are commonly used facilities not specific to any unit.
Hayden Common Facilities [Member]
Hayden Unit 2 Member
Hayden Station is a coal-fired, steam-electric generating station with two operating units. Unit 2 is a 262 megawatt plant.
Hayden Unit 2 [Member]
Hayden Unit 1 Member
Hayden Station is a coal-fired, steam-electric generating station with two operating units. Unit 1 is a 184 megawatt plant.
Hayden Unit 1 [Member]
Cap X2020 Member
CapX 2020 is a joint initiative of 11 transmission-owning utilities in Minnesota and the surrounding region to expand the electric transmission grid to ensure continued electric growth, as well as to support renewable energy expansion.
CapX2020 Transmission [Member]
Grand Meadow Line And Substation Member
Grand Meadow is a 67 unit wind farm capable of producing 100.5 megawatts and includes a subsidiary station of an electricity generation, transmission and distribution system where voltage is transformed from high to low or the reverse using transformers.
Grand Meadow Line and Substation [Member]
Sherco Substation Member
The Sherco substation is a subsidiary station of an electricity generation, transmission and distribution system where voltage is transformed from high to low or the reverse using transformers.
Sherco Substation [Member]
Sherco Common Facilities Units12 And3 Member
Supporting Sherco Unit 3 are commonly used facilities for the three coal-fired units at the Sherburne County site.
Sherco Common Facilities Units 1, 2 and 3 [Member]
Sherco Unit3 Member
Sherco Unit 3 is one of three coal-fired units at the Sherburne County site and is a 860 megawatt plant.
Sherco Unit 3 [Member]
Jointly Owned Utility Facilities Text Block
Schedule showing separately for each interest the amount of plant in service, the accumulated provision for depreciation (if available), the amount of plant under construction, and the proportionate share.
Investments by Subsidiaries in Jointly Owned Plants and Related Ownership Percentages
Extinguishment Of Debt Date
Date when the debt instrument was extinguished, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).
Extinguishment of debt, date extinguished
Unsecured Senior Debt Due July 2009 Member
A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. In the event the issuer goes bankrupt, senior secured debt holders receive priority for repayment relative to junior, senior unsecured and unsecured creditors. Series due July 15, 2009.
Unsecured Senior Notes due July 2009 [Member]
First Mortgage Bonds Due June 2019 Member
Senior secured obligations secured equally and ratably with all outstanding first mortgage bonds by the utility's assets, series due June 1, 2019.
First Mortgage Bonds due June 2019 [Member]
First Mortgage Bonds Due December 2026 Member
Senior secured obligations secured equally and ratably with all outstanding first mortgage bonds by the utility's assets, series due December 1, 2026.
First Mortgage Bonds due December 2026 [Member]
Unsecured Senior Debt Due August 2009 Member
A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. In the event the issuer goes bankrupt, senior secured debt holders receive priority for repayment relative to junior, senior unsecured and unsecured creditors. Series due August 1, 2009.
Unsecured Senior Notes due August 2009 [Member]
First Mortgage Bonds Due November 2039 Member
Senior secured obligations secured equally and ratably with all outstanding first mortgage bonds by the utility's assets, series due November 1, 2039.
First Mortgage Bonds due November 2039 [Member]
First Mortgage Bonds Due August 2010 Member
Senior secured obligations secured equally and ratably with all outstanding first mortgage bonds by the utility's assets, series due August 1, 2010.
First Mortgage Bonds due August 2010 [Member]
First Mortgage Bonds Due August 2040 Member
Senior secured obligations secured equally and ratably with all outstanding first mortgage bonds by the utility's assets, series due August 15, 2040.
First Mortgage Bonds due August 2040 [Member]
First Mortgage Bonds Due August 2015 Member
Senior secured obligations secured equally and ratably with all outstanding first mortgage bonds by the utility's assets, series due August 15, 2015.
First Mortgage Bonds due August 2015 [Member]
Unsecured Senior Debt Due May 2020 Member
A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation. Series due May 15, 2020.
Unsecured Senior Notes due May 2020 [Member]
Pollution Control Obligations Member
Represents SPS, establishes the mechanism for recovering costs associated with base plan transmission projects, which are transmission projects required to maintain reliability, and for balanced portfolio transmission projects that promote economic expansion. A municipal revenue bond used to finance a utility's investment program where the proceeds from the issuance are targeted for a specific capital investment.
Pollution Control Obligations due July 2016 [Member]
Letters Of Credit
An irrevocable undertaking to guarantee payment of a specified financial obligation.
Letters of credit
Line Of Credit Facility Commitment Fees Calculated On Unused Portion Of Lines Of Credit
The percentage amount of the available but unused credit capacity under the credit facility charged as a fee to the Company.
Commitment fees calculated on unused portion of lines of credit (in hundredths)
Line Of Credit Facility Borrowing Margin Based On Current Credit Ratings
Borrowing margin is added to the agent bank's prime rate or the applicable LIBOR to determine interest rate on the facility. Borrowing margin is based on the applicable debt ratings.
Borrowing margin based on current credit ratings (in hundredths)
Line Of Credit Facility Minimum Amount Of Indebtedness By Subsidiary To Initiate Cross Default Provisions Of All Credit Facilities
The minimum amount of default on any indebtedness by a subsidiary, comprising a threshold amount of consolidated assets, to initiate cross default provisions of all credit facility agreements.
Minimum amount of indebtedness by subsidiary to initiate cross default provisions of all credit facilities
Line Of Credit Facility Minimum Threshhold Percentage Of Subsidiary Assets To Consolidated Assets Required To Initiate Cross Default Provisions Of All Credit Facilities
Each credit facility has a cross default provision that provides the borrower will be in default on its borrowings under the facility if any of its subsidiaries, comprising a minimum percentage of consolidated assets, defaults on any indebtedness greater than a stated amount.
Minimum threshold percentage of subsidiary assets to consolidated assets required to initiate cross default provisions of all credit facilities (in hundredths)
Line Of Credit Facility Debt To Total Capitalization Ratio
The debt-to-total capitalization ratio for each entity as of the end of the period pursuant to the related financial covenants included in each credit facility agreement..
Debt-to-total capitalization ratio (in hundredths)
Line Of Credit Facility Maximum Debt To Total Capitalization Ratio Allowed
The maximum debt-to-total capitalization ratio allowed pursuant to the related financial covenants included in each credit facility agreement.
Maximum debt-to-total capitalization ratio allowed (in hundredths)
Line Of Credit Facility Number Of Financial Covenants Included In Credit Facility Agreement Requiring Maximum Debt To Total Capitalization Ratio
The number of financial covenants included in each credit facility agreement requiring the debt-to-total capitalization ratio of each entity to be less than or equal to a stated percent.
Number of financial covenants included in each credit facility agreement requiring maximum debt-to-total capitalization ratio
Line Of Credit Number Of Years Final Maturity Date Can Be Extended Subject To Majority Bank Group Approval
The number of years the Company and its subsidiaries have the right to request an extension of the final maturity date on the credit facilities. The maturity extension is subject to majority bank group approval.
Number of years final maturity date can be extended, subject to majority bank group approval (in years)
Line Of Credit Facility Maturity
The latest date when the outstanding credit facilities are required to be repaid under the original agreement between lender and borrower. May be presented in a variety of ways (for example: year only, month and year, day, month and year, and number of years).
Maturity
Line Of Credit Original Term
The length of time the credit facility would be in effect pursuant to the original credit agreement.
Original term
Credit Facilities Abstract
Credit Facilities [Abstract]
Xcel Energy Holding Company Member
Xcel Energy is a holding company, with four subsidiaries engaged primarily in the utility business. These utilities serve customers in portions of Colorado, Michigan, Minnesota, New Mexico, North Dakota, South Dakota, Texas and Wisconsin.
Xcel Energy - Holding Company [Member]
Line Of Credit Facility Affiliated Borrower Domain
Identification of each affiliate who is permitted to utilize the line of credit which may be a utility subsidiary or the holding company.
Line of credit facility affiliated borrower [Domain]
Line Of Credit Facility Affiliated Borrower Axis
The information pertaining to the line of credit by identification of each affiliate who is permitted to utilize the line of credit.
Line of credit facility affiliated borrower [Axis]
Commercial Paper Available For Issuance
The borrowing limit for commercial paper.
Commercial paper borrowing limit
Commercial Paper Abstract
Commercial Paper [Abstract]
Schedule Of Maturities Of Long Term Debt Text Block
This element captures the disclosure of total long-term debt maturities for the utility and its utility subsidiaries by maturity year for each of the five succeeding years following the latest reporting period.
Maturities of Long-Term Debt
Schedule Of Debt To Total Capitalization Ratio Text Block
This element captures the disclosure of debt to total capitalization ratios for the utility and each of its utility subsidiaries for each of the reporting periods presented.
Debt-to-Total-Capitalization Ratio
Commercial Paper Text Block
This element may be used as a single block of text to capture the entire details of commercial paper outstanding during the period.
Commercial Paper
Nuclear Fuel
Carrying amount of total nuclear fuel held as property, plant and equipment at the balance sheet date.
Nuclear fuel
Property Plant And Equipment To Be Retired
Plant assets that are pending retirment, reported net of accumulated depreciation.
Plant to be retired
Natural Gas Plant
Carrying amount of building and equipment that are used in connection with natural gas operations.
Natural gas plant
Electric Generation Plant
Carrying amount of building and equipment that are used in connection with electricity generation.
Electric plant
Natural Gas Inventory
Carrying amount as of the balance sheet date of natural gas inventory for resale to customers.
Natural gas
Fuel Inventory
Carrying amount as of the balance sheet date for fuel used to generate power plants.
Fuel
Receivables Gross Current
The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables.
Accounts receivable
Schedule Of Selected Balance Sheet Data Text Block
A schedule which lists the components of certain balance sheet accounts.
Selected Balance Sheet Data
Selected Balance Sheet Data Text Block
Details of certain balance sheet accounts.
Selected Balance Sheet Data
Deferred Financing Costs Abstract
Deferred Financing Costs [Abstract]
Restricted Cash Abstract
Restricted Cash [Abstract]
Remaining Maturity Period At Time Of Purchase For Investments To Be Considered Cash Equivalents
Remaining maturity period at time of purchase (in months) for investments to be considered cash equivalents .
Remaining maturity period at time of purchase for investments to be considered cash equivalents (in months)
Cash And Cash Equivalents Abstract
Cash and Cash Equivalents [Abstract]
Depreciation Expense Expressed As Percentage Of Average Depreciable Property
Depreciation expense expressed as a percentage of average depreciable property.
Depreciation expense expressed as a percentage of average depreciable property (in hundredths)
Property, Plant And Equipment And Depreciation Abstract
Property, Plant and Equipment and Depreciation [Abstract]
Maximum Number Of Times Texas Retail Fuel Factors Can Change Per Year
Maximum number of times Texas retail fixed fuel and purchased energy recovery factors, included in the SPS' retail electric rates, can change per year based on the projected costs of natural gas.
Maximum number of times Texas retail fuel factors can change per year
Frequency Of Rate Review Process
Frequency of rate review process (in years) for requests to recover purchased electric energy or electric fuel costs prospectively in NSP-Wisconsin's rates in Wisconsin.
Frequency of rate review process for NSP-Wisconsin's rates in Wisconsin (in years)
Frequency Of True Up Period For Cost Of Fuel And Purchased Energy Included In Rates
Frequency of true-up period (in months) for cost-of-fuel-and-purchased-energy costs to be included in the entity's rates.
Frequency of true-up period for cost-of-fuel-and-purchased-energy included in NSP-Minnesota's rates (in months)
Revenue Recognition Abstract
Revenue Recognition [Abstract]
Number Of States Subsidiaries Serve Customers
Number of states where utility subsidiaries that serve electric and natural gas customers.
Number of states subsidiaries serve customers
Number Of Utility Subsidiaries
Number of utility subsidiaries that serve electric and natural gas customers.
Number of utility subsidiaries
Principles Of Consolidation Abstract
Principles of Consolidation [Abstract]
Subsequent Event Policy Text Block
Describes the entity's accounting policy for events or transactions that occurred between the balance sheet date and the date the financial statements are issued.
Subsequent Event
Reclassifications Policy Text Block
The entire disclosure for classifying current financial statements, which may be different from classifications in the prior year's financial statements. Disclose any material changes in classification including an explanation of the reason for the change and the areas impacted.
Reclassifications
Emission Credits Or Allowances Policy Text Block
Describes the accounting and regulatory policies for emission credits or allowances. Such accounting policy has generally been based on an inventory or intangible asset model.
Emission Allowances
Renewable Energy Credits Policy Text Block
Describes the accounting and regulatory policies for renewable energy credits.
Renewable Energy Credits
Regulatory Assets And Liabilities Recognition Criteria Policy Text Block
Describes the entity's criteria for recording regulatory assets and regulatory liabilities only because they are included in the rate-setting process, and rate-related accruals and deferrals, such as amounts receivable from (or due to) customers under fuel adjustment clauses and interim rates collected prior to regulatory approval.
Regulatory Accounting
Cash And Cash Equivalents Restricted Cash And Cash Equivalents Policy Text Block
A description of an entity's cash and cash equivalents accounting policy with respect to restricted balances, including its policy for determining which items are treated as cash equivalents, the nature of any restrictions on the use of cash and cash equivalents, whether the cash and cash equivalents are insured or expose the entity to credit risk, the classification of any negative balance accounts, the carrying basis of cash equivalents, and whether the carrying amount approximates fair value.
Restricted Cash
Use Of Estimates Policy Text Block
Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.
Use of Estimates
Environmental Costs Policy Text Block
Disclosure of accounting policy for obligations that resulted from improper or other-than normal operation of a long-lived asset in the past. This accounting policy may address (1) whether the related remediation costs are expensed or capitalized, (2) whether the obligation is measured on a discounted basis, (3) the event, situation, or set of circumstances that generally triggers recognition of loss contingencies arising from the entity's environmental remediation-related obligations, and (4) the timing of recognition of any recoveries.
Environmental Costs
Outage Costs Policy Text Block
Disclosure of accounting policy for reporting outage costs, including the creation of regulatory assets or regulatory liabilities.
Nuclear Refueling Outage Costs
Nuclear Fuel Expense Policy Text Block
Describes the accounting and regulatory policies for nuclear fuel expense.
Nuclear Fuel Expense
Decommissioning Policy Text Block
Describes the accounting and regulatory policies for decommissioning or retiring nuclear generating plants.
Decommissioning
Allowance For Funds Used During Construction Policy Text Block
Describes the accounting for AFUDC (for example, component of PPE, credit to income statement), information regarding the inclusion in rates (only capitalized if its inclusion in rates is probable) and description of AFUDC (for example, represents the cost of capital used during construction).
Allowance for Funds Used During Construction Policy
Fair Value Of Financial Instruments Policy Text Block
Describes an entity's accounting policy for determining the fair value of its financial instruments.
Fair Value Measurements
Commodity Trading Operations Policy Text Block
Describes an entity's accounting policies for derivatives entered into for trading purposes and those entered into for purposes other than trading including where and when derivative financial instruments and derivative commodity instruments and their related gains (losses) are reported in the entity's statements of financial position, cash flows, and results of operations.
Commodity Trading Operations
Consolidation Subsidiaries Or Other Investments Consolidated Entities Policy Text Block
Disclosure of accounting policy for subsidiaries or other investments that are consolidated, including the accounting treatment for intercompany accounts or transactions and any noncontrolling interest.
Principles of Consolidation
Business And System Of Accounts Policy Text Block
Describes the nature of an entity's business, the major products or services it sells or provides and its principal markets, including the locations of those markets, and the system of accounts used by the entity.
Business and System of Accounts
Preferred Stock Annual Dividend Rate Per Share
Preferred stock, annual dividend rate (in dollars per share)
Preferred stock, annual dividend rate (in dollars per share)
The dividend dollar amount of a certain series of preferred stock outstanding at balance sheet date.
Common Stockholders Equity [Abstract]
Common Stockholders' Equity
Preferred Stock [Abstract]
Preferred Stock
Preferred Stockholders Equity [Abstract]
Various Eloigne Co Affordable Housing Project Notes [Member]
Fort Mc Coy System Acquisition [Member]
Fort McCoy System Acquisition [Member]
City Of La Crosse Resource Recovery Bond [Member]
Pollution Control Obligations Securing Pollution Control Revenue Bonds [Member]
Series Due Jan 1 2068 [Member]
Series Due Jan, 1, 2068 [Member]
Series Due July 1 2036 [Member]
Series Due July 1, 2036 [Member]
Series Due May 15 2020 [Member]
Series Due May 15, 2020 [Member]
Series Due April 1 2017 [Member]
Series Due April 1, 2017 [Member]
Series Due Dec 1 2010 [Member]
Series Due Dec. 1, 2010 [Member]
Series Due 2011 2045 [Member]
Series Due 2011-2045 [Member]
Series Due Oct 15 2030 [Member]
Series Due Oct. 15, 2030 [Member]
Series Due Nov 1 2021 [Member]
Series Due Nov. 1, 2021 [Member]
Series Due Sept 1 2038 [Member]
Series Due Sept. 1, 2038 [Member]
Series Due Oct 1 2018 [Member]
Series Due Oct. 1, 2018 [Member]
Series Due Sept 1 2016 [Member]
Series Due Sept. 1, 2016 [Member]
Series Due July 1 2016 [Member]
Series Due July 1, 2016 [Member]
Series Due July 1 2011 [Member]
Series Due July 1, 2011 [Member]
Senior F Series Due Oct 1 2036 [Member]
Senior F, Series Due Oct. 1, 2036 [Member]
Senior C and D Series Due Oct 1 2033 [Member]
Senior C and D, Series Due Oct. 1, 2033 [Member]
Senior G Series Due Dec 1 2018 [Member]
Senior G, Series Due Dec. 1, 2018 [Member]
Senior E Series Due Oct 1 2016 [Member]
Senior E, Series Due Oct. 1, 2016 [Member]
Through 2060 [Member]
Through 2060 [Member]
Series Due Aug 1 2038 [Member]
Series Due Aug. 1, 2038 [Member]
Series Due Sept 1 2037 [Member]
Series Due Sept. 1, 2037 [Member]
Series Due Nov 15 2020 [Member]
Series Due Nov. 15, 2020 [Member]
Series Due June 1 2019 [Member]
Series Due June 1, 2019 [Member]
Series Due Jan 1 2019 [Member]
Series Due Jan. 1, 2019 [Member]
Series Due Aug 1 2018 [Member]
Series Due Aug. 1, 2018 [Member]
Series Due Sept 1 2017 [Member]
Series Due Sept. 1, 2017 [Member]
Series Due April 1 2014 [Member]
Series Due April 1, 2014 [Member]
Series Due March 1 2013 [Member]
Series Due March 1, 2013 [Member]
Series Due Oct 1 2012 [Member]
Series Due Oct. 1, 2012 [Member]
Series Due Aug 15 2040 [Member]
Series Due Aug. 15, 2040 [Member]
Series Due Nov 1 2039 [Member]
Series Due Nov. 1, 2039 [Member]
Series Due July 1 2037 [Member]
Series Due July 1, 2037 [Member]
Series Due June 1 2036 [Member]
Series Due June 1, 2036 [Member]
Series Due July 15 2035 [Member]
Series Due July 15, 2035 [Member]
Series Due April 1 2030 [Member]
Series Due April 1, 2030 [Member]
Series Due March 1 2028 [Member]
Series Due March 1, 2028 [Member]
Series Due July 1 2025 [Member]
Series Due July 1, 2025 [Member]
Series Due Sept 1 2019 [Member]
Series Due Sept. 1, 2019 [Member]
Series Due March 1 2019 [Member]
Series Due March 1, 2019 [Member]
Series Due March 1 2018 [Member]
Series Due March 1, 2018 [Member]
Series Due Aug 15 2015 [Member]
Series Due Aug. 15, 2015 [Member]
Series Due Aug 28 2012 [Member]
Series Due Aug. 28, 2012 [Member]
Series Due Aug 1 2010 [Member]
Series Due Aug. 1, 2010 [Member]
NSP Wisconsin [Member]
NSP-Wisconsin [Member]
NSP-Wisconsin is an operating utility engaged in the generation, transmission, distribution and sale of electricity in portions of northwestern Wisconsin and in the western portion of the Upper Peninsula of Michigan.
SPS [Member]
SPS [Member]
SPS is an operating utility engaged primarily in the generation, purchase, transmission, distribution and sale of electricity in portions of Texas and New Mexico.
PSCo [Member]
PSCo [Member]
PSCo is an operating utility engaged primarily in the generation, purchase, transmission, distribution and sale of electricity in Colorado. PSCo also purchases, transports, distributes and sells natural gas to retail customers and transports customer-owned natural gas in Colorado.
NSP Minnesota [Member]
NSP-Minnesota [Member]
NSP-Minnesota is an operating utility engaged in the generation, purchase, transmission, distribution and sale of electricity in Minnesota, North Dakota and South Dakota. NSP-Minnesota also purchases, transports, distributes and sells natural gas to retail customers and transports customer-owned natural gas in Minnesota and North Dakota.
Statement Of Capitalization Longterm Debt And Equity [Abstract]
Cumulative Effect of Initial Adoption Of New Accounting Principle, Tax Effect
Adoption of new accounting guidance, tax
Tax effect of the cumulative effect of initial adoption of new accounting principle on beginning retained earnings.
Common Shareholders' Equity
Common stockholders' equity - authorized 1,000,000,000 shares of $2.50 par value; outstanding shares: Sept. 30, 2010 - 460,104,538; Dec. 31, 2009 - 457,509,263
Balance
Total common stockholders' equity
Common stockholders' equity
Balance
Total of all Stockholders' Equity items other than those pertaining to Preferred Stock. Includes the following: Common Stock at Par, Common Stock Additional Paid-in Capital, Retained Earnings, and Accumulated Other Comprehensive Income (Loss).
Deferred Credits and Other Liabilities
Total deferred credits and other liabilities
Total obligations, excluding Long-Term Debt, incurred as part of normal operations that is expected to be repaid beyond the following twelve months or one business cycle.
Other Assets, Excluding Property, Plant and Equipment
Total other assets
Sum of the carrying amounts as of the balance sheet date of all assets, excluding net property, plant and equipment, that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer.
Decommissioning Fund Investments and Other Investments
Nuclear decommissioning fund and other investments
The decommissioning fund is used to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. The line item also includes other investments not otherwise specified in the taxonomy.
Prepaid Expense And Other Assets Current
Prepayments and other
The total of the amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of a triggering event, and will be charged against earnings within one year or the normal operating cycle, if longer, and the aggregate carrying amount of current assets, as of the balance sheet date, not separately presented elsewhere in the balance sheet.
Accrued Unbilled Revenues
Accrued unbilled revenues
The amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms.
Issuance Of Common Stock For Senior Convertible Notes
Issuance of common stock for senior convertible notes
The fair value of stock granted to the holder in exchange for senior convertible notes by the maturity date of the notes.
Issuance Of Common Stock For Reinvested Dividends And 401 k Plans
Issuance of common stock for reinvested dividends and 401(k) plans
The fair value of stock or stock options granted to stockholders who choose to have dividends reinvested in the company's stock and the fair value of stock granted to employees as a contribution to the employees' 401(k) plans.
Other Noncash Financing Items [Abstract]
Supplemental disclosure of non-cash financing transactions:
Other Noncash Investing Items [Abstract]
Supplemental disclosure of non-cash investing transactions:
Increase (Decrease) in Operating Liabilities, Noncurrent
Change in other noncurrent liabilities
The net change during the reporting period in other noncurrent operating liabilities not otherwise defined in the taxonomy.
Increase (Decrease) in Operating Assets, Noncurrent
Change in other noncurrent assets
The net change during the reporting period in other noncurrent operating assets not otherwise defined in the taxonomy.
Increase (Decrease) in Operating Liabilities, Current
Other current liabilities
The net change during the reporting period in other current operating liabilities not otherwise defined in the taxonomy.
Increase (Decrease) in Operating Assets, Current
Other current assets
The net change during the reporting period in other current operating assets not otherwise defined in the taxonomy.
Nuclear Fuel Amortization
Nuclear fuel amortization
The expense charged against earnings for the periodic recognition of costs previously incurred before nuclear fuel is fabricated and loaded.
Depreciation, Amortization and Accretion, Net, Cash Flow Impact
Depreciation and amortization
The cash flow impact of the aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by (used in) operations using the indirect method.
Income Loss From Continuing Operations Before Income Taxes And Minority Interest
Sum of operating profit and nonoperating income (expense) before income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.
Income from continuing operations before income taxes
Income from continuing operations before income taxes
Conservation And Demand Side Management Program Expenses
Conservation and demand side management program expenses
Costs incurred for energy conservation, weatherization and other programs to conserve or manage energy use by customers.
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies [Policies] [Abstract]
Summary of Significant Accounting Policies [Details] [Abstract]
Accounting Pronouncements [Abstract]
Selected Balance Sheet Data [Abstract]
Selected Balance Sheet Data [Tables] [Abstract]
Selected Balance Sheet Data [Details] [Abstract]
Nuclear Fuel Accumulated Amortization
The cumulative amount of amortization related to nuclear fuel that has been recognized in the income statement.
Less accumulated amortization
Borrowings and Other Financing Instruments [Abstract]
Borrowings and Other Financing Instruments [Tables] [Abstract]
Borrowings and Other Financing Instruments [Details] [Abstract]
Maturities of long-term debt details used in millions [Abstract]
Maturities of long-term debt [Abstract]
Joint Ownership of Generation, Transmission and Gas Facilities [Abstract]
Joint Ownership of Generation, Transmission and Gas Facilities [Tables] [Abstract]
Joint Ownership of Generation, Transmission and Gas Facilities [Details] [Abstract]
Income Taxes [Abstract]
Income Taxes [Tables] [Abstract]
Income Taxes [Details] [Abstract]
Unrecognized Tax Benefits Interest Payable
This element represents the amount of interest payable as of the date of the statement of financial position for unrecognized tax benefits computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.
Payable for interest related to unrecognized tax benefits at Jan. 1
Payable for interest related to unrecognized tax benefits at Dec. 31
Preferred and Common Stock [Abstract]
Preferred and Common Stock [Tables] [Abstract]
Preferred and Common Stock [Details] [Abstract]
Share-Based Compensation Disclosure [Abstract]
Share-Based Compensation [Abstract]
Share-Based Compensation [Tables] [Abstract]
Share-Based Compensation [Details] [Abstract]
Benefit Plans and Other Postretirement Benefits [Abstract]
Benefit Plans and Other Postretirement Benefits [Tables] [Abstract]
Benefit Plans and Other Postretirement Benefits [Details] [Abstract]
Defined Benefit Plan Target Asset Allocations Total
The aggregate target allocation percentage of investments to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.
Total (in hundredths)
Amounts Related To Funded Status Of Plan Total
Total amount related to the funded status of plans which has been recorded on the balance sheet based upon the expected recovery in rates.
Total
Defined Benefit Plan, Net Periodic Benefit Cost before Regulatory Adjustment
The total amount of net periodic benefit cost, before regulatory adjustments, for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain or loss, prior service cost or credit, transition asset or obligation, and gain or loss due to settlements or curtailments, before regulatory adjustments.
Net periodic benefit cost (credit)
Other Income, Net [Abstract]
Other Income, Net [Tables] [Abstract]
Other Income, Net [Details] [Abstract]
Derivative Instruments and Fair Value Measurements [Abstract]
Derivative Instruments and Fair Value Measurements [Tables] [Abstract]
Derivative Instruments and Fair Value Measurements [Details] [Abstract]
Fair Value Assets Measured On Recurring Basis Derivative Assets Current
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Total current derivative assets
Fair Value Assets Measured On Recurring Basis Derivative Assets Noncurrent
This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.
Total noncurrent derivative assets
Fair Value Liabilities Measured On Recurring Basis Derivative Liabilities Current
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Total current derivative liabilities
Fair Value Liabilities Measured On Recurring Basis Derivative Liabilities Noncurrent
This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.
Total noncurrent derivative liabilities
Fair Value, Measurement with Unobservable Inputs Reconciliation Recurring Basis, Net Value
This element represents net assets and liabilities measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.
Balance at beginning of period
Balance at end of period
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Assets And Liabilities Total Transfers Net
This element represents [net] transfers in to and out of assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.
Transfers that occurred between Level 2 and Level 3, total assets and liabilities
Financial Instruments [Abstract]
Financial Instruments [Tables] [Abstract]
Financial Instruments [Details] [Abstract]
Rate Matters [Abstract]
Rate Matters [Tables] [Abstract]
Rate Matters [Details] [Abstract]
Requested Rate Increase Decrease
The entity's original requested amount of increase (decrease) to existing electric rates for 2010, filed with the Public Service Commission of Wisconsin.
Entity's requested rate increase (decrease)
Adjusted Rate Increase
The entity's adjusted requested amount of increase (decrease) to existing electric rates for 2011, filed with the Public Utility Commission of Texas.
Adjusted rate increase
Commitments and Contingent Liabilities [Abstract]
Commitments and Contingent Liabilities [Tables] [Abstract]
Commitments and Contingent Liabilities [Details] [Abstract]
Unrecorded Unconditional Purchase Obligation Estimated Future Payments
The total of estimated future payments of an unrecorded unconditional purchase obligation.
Total
Nuclear Obligations [Abstract]
Nuclear Obligations [Tables] [Abstract]
Nuclear Obligations [Details] [Abstract]
Estimated Decommissioning Cost Obligation In Current Dollars
Estimated decommissioning cost obligation in current year dollars based on most recently approved periodic site-specific cost study and effect of escalating costs to current year dollars.
Estimated decommissioning cost obligation (in current dollars)
Estimated Future Decommissioning Costs Undiscounted
Estimated undiscounted future decommissioning costs based on periodic site-specific cost study and effect of escalating costs to anticipated payment date.
Estimated future decommissioning costs (undiscounted)
Effect Of Discounting Obligation Using Risk Free Interest Rate
Decrease in estimated decommissioning cost obligation due to discounting the obligation using a risk-free interest rate.
Effect of discounting obligation (using risk-free interest rate)
Discounting Decommissioning Obligation Compared To Assets Currently Held In Trust
Net amount of discounted decommissioning cost obligation compared to assets held in external decommissioning trust.
Excess assets in external trust compared to discounted decommissioning obligation
Regulatory Assets and Liabilities [Abstract]
Regulatory Assets and Liabilities [Tables] [Abstract]
Regulatory Assets and Liabilities [Details] [Abstract]
Segments and Related Information [Abstract]
Segments and Related Information [Tables] [Abstract]
Segments and Related Information [Details] [Abstract]
Summarized Quarterly Financial Data (Unaudited) [Abstract]
Summarized Quarterly Financial Data (Unaudited) [Tables] [Abstract]
Summarized Quarterly Financial Data (Unaudited) [Details] [Abstract]
Asset Acquistion and Sale [Abstract]
Asset Acquistion and Sale [Tables] [Abstract]
Asset Acquistion and Sale [Details] [Abstract]
Schedule I Condensed Financial Statements and Related Notes [Abstract]
Schedule I Condensed Financial Statements and Related Notes [Tables] [Abstract]
Schedule I Condensed Financial Statements and Related Notes [Details] [Abstract]
Schedule I - Condensed Financial Statements and Related Notes [Details]
Total income
The total income for the period.
Total expenses and other deductions
Sum of operating expenses, other income, and interest charges and financing costs for the period.
Schedule II Valuation and Qualifying Accounts [Abstract]
Schedule II Valuation and Qualifying Accounts [Tables] [Abstract]
Schedule II Valuation and Qualifying Accounts [Details] [Abstract]
First Mortgage Bonds due November 2020 [Member]
First Mortgage Bonds Due November 2020 Member
A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation. Series due November 15, 2020.
Fair Value Assets And Liabilities Measured On Recurring Basis Disclosure Items Transfers [Axis]
This element represents the balance sheet classification of transfers between Level 2 and Level 3 of assets and liabilities measured on a recurring basis.
Fair Value Assets and Liabilities Measured on Recurring Basis Disclosure Items Transfers
Summarization of information concerning assets and liabilities which are measured at fair value on a recurring basis and transferred between Level 2 and Level 3 measurements.
Fair Value Assets and Liabilities Measured on Recurring Basis Transfers [Table]
Fair Value Assets and Liabilities Measured on Recurring Basis Transfers
Percentage Of Next 20 Million Of Margins
This element represents the percentage of the next $20 million of margins which will go to the entity during the pilot period.
10 Million to 30 million (in hundredths)
Net benefit cost (credit) recognized for financial reporting
An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.
Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Rate Of Return On Assets
Expected average long-term rate of return on assets
Nuclear Fuel Supply Agreements [Member]
Nuclear Fuel [Member]
An acquired nuclear fuel supply agreement, providing benefits for a finite period of time, under which a power company buys nuclear fuel to meet the requirements of one of its power plants (under specified terms for specified time periods).
Granted, weighted average grant date fair value (in dollars per share)
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period For Stock Options
Description of the period of time over which an employee's right to exercise an option is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).
Vesting period for stock options after grant date
Implemented Rate Increase Phase 2
Implemented rate increase - Phase 2
The entity's implemented amount of increase (decrease) to existing electric rates for phase 2, approved by the Colorado Public Utilities Commission.
Electric Generation [Member]
Electric Transmission [Member]
Jointly Owned Gas Transportation Member
Jointly owned plant in connection with the transportation of natural gas.
Gas Transportation [Member]
Jointly Owned Utility Plant Name Axis
Identifies the name of the jointly owned utility plant.
Jointly Owned Utility Plant Name [Axis]
Jointly Owned Utility Plant Name Domain
The name of the jointly owned utility plant.
Jointly Owned Utility Plant Name [Domain]
Comanche Common Facilities Member
Commonly used facilities not specific to the Comanche Unit 3.
Comanche Common Facilities [Member]
Rifle To Avon Member
The pipeline connecting Rifle, Colorado to Avon, Colorado.
Rifle to Avon [Member]
Jointly Owned Utility Plant Proportionate Ownership Share Lower Range
The lower range of the proportionate share of interest (percent) in a jointly owned utility plant.
Ownership %, lower range (in hundredths)
Jointly Owned Utility Plant Proportionate Ownership Share Upper Range
The upper range of the proportionate share of interest (percent) in a jointly owned utility plant.
Ownership %, upper range (in hundredths)
Jointly Owned Utility Plant Proportionate Ownership Percentage Share
The proportionate share of interest in a jointly owned utility plant.
Ownership %
Regulatory Liability Amortization Period
The amortization period for recovery of the individual regulatory liability in a schedule of regulatory liabilities.
Regulatory liability, remaining amortization period
Vehicle Fuel And Other Commodity Member
Derivative instrument whose primary underlying risk is tied to vehicle fuel and other commodity prices.
Vehicle Fuel and Other Commodity [Member]
Fair value changes recognized during the period in other comprehensive income (losses)
Derivative Instruments Gain Loss Recognized In Regulatory Assets And Liabilities Effective Portion Net
The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in regulatory assets and liabilities during the current period.
Fair value changes recognized during the period in regulatory assets and liabilities
Pre-tax amounts reclassified into income during the period from other comprehensive income
Cash Flow Hedge Gain Loss Reclassified To Regulatory Assets And Liabilities Net
The amount of net gains (losses) on a cash flow hedge reclassified in the period to earnings from regulatory assets and liabilities.
Pre-tax amounts reclassified into income during the period from regulatory assets and liabilities
Pre-tax gains (losses) recognized during the period in income
Current Tax Credits
The component of income tax expense for the period representing the current tax credits.
Current tax credits
Estimated Cost Of Capital Requirements In Next Twelve Months
Represents the estimated cost of capital requirements related to of the company and its subsidiaries and its capital expenditure programs expected to be incurred within the next twelve months.
2011
Estimated Cost Of Capital Requirements In Year Two
Represents the estimated cost of capital requirements related to of the company and its subsidiaries and its capital expenditure programs expected to be incurred in year two following the balance sheet date.
2012
Estimated Cost Of Capital Requirements In Year Three
Represents the estimated cost of capital requirements related to of the company and its subsidiaries and its capital expenditure programs expected to be incurred in year three following the balance sheet date.
2013
Estimated Cost Of Capital Requirements In Year Four
Represents the estimated cost of capital requirements related to of the company and its subsidiaries and its capital expenditure programs expected to be incurred in year four following the balance sheet date.
2014
Estimated Cost Of Capital Requirements In Year Five
Represents the estimated cost of capital requirements related to of the company and its subsidiaries and its capital expenditure programs expected to be incurred in year five following the balance sheet date.
2015
Estimated Capital Investment For Capacity Increases At Nuclear Plants
The total estimated capital investment for nuclear plants for a five year period subsequent to year end.
Estimated capital investment between 2011 and 2015 for capacity increases at the Monticello and Prairie Island nuclear plants
Investment In Wind Generation Projects In Current Period
Represents the estimated capital investment for wind generation projects through the balance sheet date.
Cumulative investment in wind generation projects
Investment In Wind Generation Projects Planned Within One Year After Period End
Represents the estimated capital investment for wind generation projects planned within the next twelve months.
Investment in wind generation projects planned in 2011
Proposed Construction To Repower Plant
The amount of proposed construction costs to repower a plant that is estimated to be incurred over the five years subsequent to the balance sheet date.
Proposed construction costs over the next five years to repower the Black Dog plant
Amount of natural gas generation installed by 2016 (in MW)
Amount Of Natural Gas Generation Installed By 2016
The amount of megawatts installed in relation to proposed construction costs that is estimated to be incurred over the next five years subsequent to the balance sheet date.
Cost Of Planned New Construction In Accordance With Clean Air Clean Jobs Act
Cost of planned new construction over the next seven years in accordance with the Clean Air-Clean Jobs Act
The amount of planned construction costs aimed to reduce annual emissions of NOx in accordance with the Clean Air-Clean Jobs Act that is estimated to be incurred over the seven years subsequent to the balance sheet date.
Coal [Member]
Payments For Capacity Purchase Power Agreements Executory Contracts
Payments for capacity for purchase power agreements accounted for as executory contracts and included in electric fuel and purchased power expenses.
Payments for capacity for purchase power agreements accounted for as executory contracts
Additional Construction Costs Anticipated
Additional construction costs anticipated by the investee accounted for under the equity method of accounting.
Additional construction costs anticipated by WYCO
The percentage of additional construction costs that will be paid by the entity to finalize construction.
Percentage Of Additional Construction Costs Paid To Finalize Construction
Percentage of additional construction costs that will be paid to finalize construction (in hundredths)
Percentage Of Capital Lease Obligation Eliminated
The percentage of the capital lease obligation that is eliminated in the consolidated balance sheet.
Percentage of the capital lease obligation eliminated related to WYCO (in hundredths)
Capital Lease Obligations [Member]
Long-term Purchase Commitment [Table]
Long-term Purchase Commitment by Category of Item Purchased [Axis]
Long-term Purchase Commitment, Category of Item Purchased [Domain]
Long-term Purchase Commitment [Line Items]
Estimated Cost Of Relocating Village Low End Of Range
The low end of the range of estimated costs to relocate the village of Kivalina, Alaska for which the entity believes the claims asserted are without merit and for which no accrual has been recorded.
Estimated cost of relocating the village of Kivalina, low end of range
Estimated Cost Of Relocating Village High End Of Range
The high end of the range of estimated costs to relocate the village of Kivalina, Alaska for which the entity believes the claims asserted are without merit and for which no accrual has been recorded.
Estimated cost of relocating the village of Kivalina, high end of range
Litigation Abstract
Qwest vs. Xcel Energy Inc. [Abstract]
Litigation 2 Abstract
Stone & Webster, Inc. vs. PSCo [Abstract]
Minnesota Electric Rate Case Abstract
NSP-Minnesota Electric Rate Case
Entitys Original Requested Electric Rate Increase Decrease Mpuc
The entity's original requested amount of increase (decrease) to existing electric rates for 2011, filed with the Minnesota Public Utilities Commission.
Entity's original requested electric rate increase (decrease)
Percentage Increase In Entitys Original Requested Electric Rate Increase Mpuc
The percentage increase in the entity's original requested amount of increase (decrease) for 2011 to existing electric rates, filed with the Minnesota Public Utilities Commission.
Percentage increase in entity's original requested electric rate increase (in hundredths)
Entitys Original Requested Percent Return On Equity Electric Mpuc
Rate of return on equity that the entity's original revenue increase requested represented through an electric rate case proceeding for 2011, filed with the Minnesota Public Utilities Commission.
Entity's original requested percent return on equity (in hundredths)
Electric Rate Base Mpuc
The entity's adjusted requested value established on which the entity is allowed to earn a particular rate of return on electric operations for 2011, filed with the Minnesota Public Utilities Commission.
Electric rate base
Entitys Original Requested Equity Ratio Percent Electric Mpuc
The ratio of equity to total capitalization (debt plus equity) used in the entity's original requested electric rate regulatory proceeding for 2011, filed with the Minnesota Public Utilities Commission.
Entity's original requested equity ratio percent (in hundredths)
Entitys Revised Electric Rate Increase Decrease
The entity's revised requested amount of increase (decrease) to existing electric rates for 2011, filed with the Minnesota Public Utilities Commission.
Entity's revised electric rate increase (decrease)
Entitys Additional Requested Electric Rate Increase Decrease Mpuc
The entity's additional requested amount of the increase to existing electric rates for 2012, filed with the Minnesota Public Utilities Commission.
Entity's additional requested electric rate increase (decrease)
Additional Percentage Increase In Entitys Requested Electric Rate Increase Mpuc
The percentage increase in the entity's additional requested amount of increase (decrease) to the original requested amount of increase (decrease) to existing electric rates for 2012, filed with the Minnesota Public Utilities Commission.
Additional percentage increase in entity's requested electric rate increase (in hundredths)
Amount Collected From Ratepayers Through Riders To Be Transferred Into Base Rates
The amount projected to be collected from ratepayers through riders to be transferred into rates at the conclusion of the 2011 electric rate case with the implementation of final rates.
Amount projected to be collected from ratepayers through riders to be transferred into base rates
Interim Electric Rate Increase Implemented Mpuc
Interim electric rate increase implemented
The interim electric rate increase (decrease) implemented for 2011, approved by the Minnesota Public Utilities Commission.
Entitys Approved Requested Rate Increase Decrease
The entity's approved requested amount of increase (decrease) to existing gas rates for 2010, filed with the Minnesota Public Utilities Commission.
Revenue increase (decrease) approved
Entitys Approved Requested Percent Return On Equity
Approved rate of return on equity that the entity's revised revenue increase represented through a gas rate case proceeding for 2010, filed with the Minnesota Public Utilities Commission.
Entity's approved requested percent return on equity (in hundredths)
Conservation Improvement Rider Abstract
Conservation Improvement Program (CIP) Rider
Electric Cip Expenses And Financial Incentives Recovery Requested
The amount of revenue increase (decrease) requested for electric conservation improvement program expenses and financial incentives requested by the entity.
Electric CIP expenses and financial incentives recovery requested
Natural Gas Cip Expenses And Financial Incentives Recovery Requested
The amount of revenue increase (decrease) requested for natural gas conservation improvement program expenses and financial incentives requested by the entity
Natural gas CIP expenses and financial incentives recovery requested
Approximate Unrecovered Electric Cip Balance At End Of 2012
The approximate unrecovered electric conservation improvement program expenses balance at the end of 2012, after acceleration of rider cost recovery.
Approximate unrecovered electric CIP balance at the end of 2012
Estimated Recovery Of Electric Cip Expenses Through Rider
The estimated recovery of electric conservation improvement program expenses through the conservation improvement program rider during the November 2010 to September 2011 timeframe.
Estimated recovery of electric CIP expenses through rider
Estimated Recovery Of Electric Cip Expenses Through Conservation Cost Recovery Charge Component Of Base Rates
The estimated recovery of electric conservation improvement program expenses through conservation cost recovery charge component of rates.
Estimated recovery of electric CIP expenses through rates
Approximate Unrecovered Natural Gas Cip Balance At End Of 2011
The approximate unrecovered natural gas conservation improvement program expenses balance at the end of 2011, after acceleration of rider cost recovery.
Approximate unrecovered natural gas CIP balance at the end of 2011
Estimated Recovery Of Natural Gas Cip Expenses Through Rider
The estimated recovery of natural gas CIP expenses through the CIP rider during the December 2010 to September 2011 timeframe.
Estimated recovery of natural gas CIP expenses through rider
Estimated Recovery Of Natural Gas Cip Expenses Through Conservation Cost Recovery Charge Component Of Base Rates
The estimated recovery of natural gas conservation improvement program expenses through conservation cost recovery charge component of base rates.
Estimated recovery of natural gas CIP expenses through rates
North Dakota Electric Rate Case Abstract
NSP-Minnesota North Dakota Electric Rate Case
Entitys Original Requested Electric Rate Increase Decrease Ndpsc
The entity's original requested amount of increase (decrease) to existing electric rates for 2011, filed with the North Dakota Public Service Commission.
Entity's original requested electric rate increase (decrease)
Percentage Increase In Entitys Original Requested Electric Rate Increase Ndpsc
The percentage increase in the entity's original requested amount of increase (decrease) for 2011 to existing electric rates, filed with the North Dakota Public Service Commission.
Percentage increase in entity's original requested electric rate increase (in hundredths)
Entitys Original Requested Percent Return On Equity Electric Ndpsc
Rate of return on equity that the entity's original revenue increase requested represented through a electric rate case proceeding for 2011, filed with the North Dakota Public Service Commission.
Entity's original requested percent return on equity (in hundredths)
Electric Rate Base Ndpsc
The entity's adjusted requested value established on which the entity is allowed to earn a particular rate of return on electric operations for 2011, filed with the North Dakota Public Service Commission.
Electric rate base
Entitys Original Requested Equity Ratio Percent Electric Ndpsc
The ratio of equity to total capitalization (debt plus equity) used in the entity's original requested electric rate regulatory proceeding for 2011, filed with the North Dakota Public Service Commission.
Entity's original requested equity ratio percent (in hundredths)
Entitys Additional Requested Electric Rate Increase Decrease Ndpsc
The entity's additional requested amount of the increase to existing electric rates requested for 2011 and effective 2012, filed with the North Dakota Public Service Commission.
Entity's additional requested electric rate increase (decrease)
Interim Electric Rate Increase Implemented Ndpsc
The interim electric rate increase (decrease) implemented for 2011, approved by the North Dakota Public Service Commission.
Interim electric rate increase implemented
Percentage Increase In Entitys Implemented Electric Rate Increase
The percentage increase in the entity's implemented amount of increase (decrease) to existing electric rates, approved by the Public Service Commission of Wisconsin.
Percentage increase in entity's implemented electric rate increase (in hundredths)
Overall Approved Rate Increase
The entity's overall approved amount of increase (decrease) to existing electric rates for 2011, approved by the Colorado Public Utilities Commission.
Overall approved rate increase
Impact Of Rate Design Changes Specific To Seasonal Rates
The increase to electric revenues and margin due to rate design changes.
Impact of rate design changes specific to seasonal rates
Entitys Approved Revenue Increase Decrease Without Including Long Term Debt Interest
The entity's approved amount of increase (decrease) to existing electric rates for 2011, filed with the Colorado Public Utilities Commission.
Entity's approved revenue increase (decrease) without including long-term debt interest
Entitys Original Requested Gas Rate Increase Decrease
The entity's original requested amount of increase (decrease) to existing gas rates for 2011, filed with the Colorado Public Utilities Commission.
Entity's original requested gas rate increase (decrease)
Entitys Original Requested Percent Return On Equity Gas
Rate of return on equity that the entity's original revenue increase requested represented through a gas rate case proceeding for 2011, filed with the Colorado Public Utilities Commission.
Entity's original requested percent return on equity (in hundredths)
Gas Rate Base
The entity's adjusted requested value established on which the entity is allowed to earn a particular rate of return on gas operations for 2011, filed with the Colorado Public Utilities Commission.
Gas rate base
Entitys Original Requested Equity Ratio Percent Gas
The ratio of equity to total capitalization (debt plus equity) used in the entity's original requested gas rate regulatory proceeding for 2011, filed with the Colorado Public Utilities Commission.
Entity's original requested equity ratio percent (in hundredths)
Proposed Percentage Of Margin Associated With Sale Of Stand Alone Recs To Go To Entity
This element represents the percentage of margins associated with the sale of stand-alone Renewable Energy Credits which is proposed to go to the entity, subject to approval by the Colorado Public Utilities Commission.
Proposed percentage of margin associated with the sale of stand-alone RECs to go to the entity (in hundredths)
Proposed Percentage Of Margin Associated With Sale Of Stand Alone Recs To Go To Customers
This element represents the percentage of margins associated with the sale of stand-alone Renewable Energy Credits which is proposed to go to the customers, subject to approval by the Colorado Public Utilities Commission.
Proposed percentage of margin associated with the sale of stand-alone RECs to go to customers (in hundredths)
Adjusted Total Requested Cost Of Service
The gross reduction to the electric rate case increase requested for 2011 due to reduced cost of service relating to the sale of electric distribution assets, filed with the Public Utility Commission of Texas.
Adjusted total requested cost of service
Net Requested Cost Of Service
The net reduction to the electric rate case increase requested for 2011 due to reduced cost of service relating to the sale of electric distribution assets, filed with the Public Utility Commission of Texas.
Net requested cost of service
Total Rate Increase Implemented
The entity's implemented amount of increase (decrease) to existing electric rates for 2011, approved by the Public Utility Commission of Texas.
Total rate increase implemented
Rate Increase Due To Transfer Of Two Rate Riders
The entity's implemented amount of increase in electric rates due to the transfer of rider revenue into rates approved by the Public Utility Commission of Texas.
Rate increase due to transfer of two rate riders
Traditional Rate Increase
The entity's implemented amount of increase to electric rates due to a traditional rate increase approved by the Public Utility Commission of Texas.
Traditional rate increase
Deferred Pension And Benefit Costs
The amount of pension and benefit costs the entity is allowed to defer, previously requested in the rate case, approved by the Public Utility Commission of Texas.
Deferred pension and benefit costs
Deferred Renewable Energy Credits
The amount of renewable energy credits the entity is allowed to defer, previously requested in the rate case, approved by the Public Utility Commission of Texas.
Deferred renewable energy credits
Increase In Rates
The entity's implemented amount of increase (decrease) to existing electric rates for 2012, approved by the Public Utility Commission of Texas.
Increase in rates
Energy Efficiency Cost Recovery Factor Rider
The amount of the energy efficiency cost recovery factor rider permitted by the Public Utility Commission of Texas to be requested by the entity.
Energy efficiency cost recovery factor rider
Effective Rate Increase
The entity's total possible amount of increase (decrease) to existing electric rates for 2012, if the energy efficiency cast recovery factor rider is approved by the Public Utility Commission of Texas.
Effective rate increase
Maximum Pension And Benefit Costs To Be Tracked And Deferred
The maximum amount of pension and benefit costs that the entity is allowed to track and defer above the test year levels.
Maximum pension and benefit costs to be tracked and deferred
Maximum Renewable Energy Credits To Be Tracked And Deferred
The maximum amount of renewable energy credits that the entity is allowed to track and defer.
Maximum renewable energy credits to be tracked and deferred
Potential Reduction In Calculated Tcrf Revenue Requirement
The amount the calculated transmission cost recovery factor revenue requirement must be reduced if the entity files a transmission cost recovery factor application before the effective date of rates in its next rate case.
Potential reduction in the calculated TCRF revenue requirement
Reduction To System Cost
Amount of reduction to power purchases, low end of range (MW)
Amount complainants must reduce power purchases, low end of range, in megawatts, by 2012.
Amount complainants must reduce power purchases, high end of range, in megawatts, by 2012.
Final System Cost
Amount of reduction to power purchases, high end of range (MW)
Anticipated Size New Credit Facilities To Replace Existing Agreements
The total approximate anticipated size of the new credit facilities company plans to enter into to replace the existing agreements.
Anticipated size of new credit facilities to replace the existing agreements
Amount Commercial Paper Program Subsidiary Received Regulatory Approval To Establish
Amount of commercial paper program NSP-Wisconsin received regulatory approval to establish. This approval was given along with the ability to enter into a back-up credit facility.
Amount of commercial paper program NSP-Wisconsin received regulatory approval to establish
Junior Subordinated Notes Due 2068 [Member]
Junior subordinated long-term debt due 2068. Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.
Junior Subordinated Notes due January 2068 [Member]
Estimated Cost Minnesota Joint Initiative
The estimated cost of CapX2020 initiative.
Estimated cost of CapX2020 initiative
Approximate Projected Share Investment Jointly Owned Utility Plants
The approximate projected share of the investment in NSP-Minnesota and NSP-Wisconsin.
Approximate projected share of the investment of NSP-Minnesota and NSP-Wisconsin
Previously recognized Medicare Part D subsidies (in hundredths)
Equity forward instruments (in shares)
Amount Of Convertible Senior Notes
Convertible senior notes
Decommissioning Trust Assets Cost Amount
Cost
Related Party Transactions
Other Parent Company Disclosures
Schedule of Related Party Transactions, by Related Party [Table]
Related Party Transactions, by Related Party [Axis]
Related Party [Domain]
Xcel Energy Services Inc [Member]
Xcel Energy Services Inc. is the service company for the Xcel Energy holding company.
Xcel Energy Services Inc. [Member]
Xcel Energy Ventures Inc [Member]
Xcel Energy Ventures Inc. [Member]
Related Party Transaction [Line Items]
Accounts Receivable
Accounts Payable
Cash dividends paid to Xcel Energy by subsidiaries
Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions Discontinued Operations
The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns for discontinued operations, excluding amounts pertaining to examined tax returns.
Additions for tax positions of prior years - discontinued operations
Amount accrued for penalties related to unrecognized tax benefits
Unrecognized Tax Benefits Income Tax Penalties Accrual Reversal
Reversal of the amount of statutory penalties previously accrued as of the date of the statement of financial position for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.
Reversal of penalties accrued related to unrecognized tax benefits
Entitys Implemented Electric Rate Increase Decrease
The entity's implemented amount of increase (decrease) to existing wholesale rates, subject to approval by the Federal Energy Regulatory Commission.
Entity's implemented rate increase (decrease)
Entitys 2010 Gas Rate Case [Abstract]
PSCo 2010 Gas Rate Case
Additional Percentage Increase In Entitys Requested Electric Rate Increase Ndpsc
The percentage increase in the entity's additional requested amount of increase (decrease) to the original requested amount of increase (decrease) to existing electric rates for 2011 and effective 2012, filed with the North Dakota Public Service Commission.
Additional percentage increase in entity's requested electric rate increase (in hundredths)
Regulatory Liability
The amount for the individual regulatory current and noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.
Regulatory liability
Health care costs trend rate - initial
Expected contribution to postretirement health care plans during 2011
Ultimate health care trend assumption rate (in hundredths)
Regulatory Assets Related To Nonqualified Pension Plan Current
The current amount of regulatory assets associated with a non-qualified pension plan.
Regulatory assets related to non-qualified pension plan, current
Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions Continuing Operations
Additions for tax positions of prior years - continuing operations
The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns for continuing operations, excluding amounts pertaining to examined tax returns.
Junior Subordinated Notes [Member]
Longterm Debt Type And Instrument [Axis]
Pertinent information about each long-term debt arrangement including the carrying amount as of the balance sheet date, by the type of long-term debt and underlying debt instrument. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the company, if longer.
Long-term Debt, Type and Instrument [Axis]
Longterm Debt Type And Instrument [Domain]
Gain On Sale Of Electric Distribution System Assets
Gain on the sale of fixed assets which would otherwise be reflected as income, that are deferred as regulatory liabilities based on the expectation they will be refunded to customers through the ratemaking process.
Gain on sale of assets which will be shared with retail customers in Texas
Leases
Variable Interest Entities
Conservation Programs [Text Block]
Describes the entity's accounting policy for programs to assist customers in conserving energy and reducing peak demand on the electric and natural gas systems.
Conservation Programs
Guarantees [Text Block]
Guarantees
Describes an entity's accounting policies for guarantees and the methodology used in determining the amount of such liabilities.
Estimated pension funding contributions for 2012, lower range
The lower end of the range of the employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in 2012 as of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.
Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Lower Range
Defined Benefit Plan Estimated Future Employer Contributions In Next Fiscal Year Upper Range
The upper end of the range of the employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in 2012 as of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.
Estimated pension funding contributions for 2012, upper range
Represents the estimated cost of capital requirements related to of the company and its subsidiaries and its capital expenditure programs expected to be incurred within the next twelve months.
The current amount of regulatory assets associated with non-qualified pension plan.