Name:	psco_ConservationAndDemandSideManagementProgramExpenses
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Cost of electricity sold during the reporting period, operations of which is regulated by a federal or state agency.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cost of generation, transmission, and distribution of [natural] gas, which are regulated by a federal, state, or local government or agency.

No definition available.

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Total costs of sales and operating expenses for the period.

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Period Type:	duration

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Revenue derived from the regulated (by a federal, state, or local government or agency) generation, transmission and distribution of electricity.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Revenue derived from the regulated (by a federal, state, or local government or agency) generation, transmission and distribution of [natural] gas.

Name:	us-gaap_GasDomesticRegulatedRevenue
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Data Type:	xbrli:monetaryItemType
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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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Data Type:	xbrli:monetaryItemType
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Name Accounting Standards Codification

-Topic 235

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-Subparagraph (SX 210.4-08.(h))

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-Number 210

-Section 08

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-Glossary Income Tax Expense (or Benefit)

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Interest and debt related expenses associated with nonoperating financing activities of the entity.

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Balance Type:	debit
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Amount of the cost of borrowed funds accounted for as interest expense.

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-Topic 835

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-Subparagraph (SX 210.9-04.9)

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Name Accounting Standards Codification

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-Glossary Other Comprehensive Income

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-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

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-Topic 944

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-Paragraph 1

-Subparagraph (SX 210.7-04.19)

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-Topic 225

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-Paragraph 2

-Subparagraph (SX 210.5-03.18)

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-Subparagraph (SX 210.7-04.22)

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-Number 210

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-Section 04

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Name:	us-gaap_NetIncomeLoss
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The net result for the period of deducting operating expenses from operating revenues.

No definition available.

Name:	us-gaap_OperatingIncomeLoss
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Data Type:	xbrli:monetaryItemType
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Other costs incurred during the reporting period related to other revenue generating activities.

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-Topic 225

-SubTopic 10

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-Paragraph 2

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-Number 210

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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-Subparagraph (SX 210.5-03.9)

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Revenues from the sale of other goods or rendering of other services, not elsewhere specified in the taxonomy; net of (reduced by) sales adjustments, returns, allowances, and discounts.

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The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount capitalized of allowance for funds used during construction.

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-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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Name:	us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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

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-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Name Regulation S-X (SX)

-Number 210

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Name:	us-gaap_Revenues
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Name:	us-gaap_RevenuesAbstract
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Data Type:	xbrli:stringItemType
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All taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax.

Name:	us-gaap_TaxesExcludingIncomeAndExciseTaxes
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of operating expense for depreciation and amortization of regulated operation.

Name:	us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The amount of operating expenses for the period that are associated with the utility's normal revenue producing operation; including selling, general, and administrative expenses, costs incurred for routine plant repairs and maintenance, and operations.

No definition available.