XML 71 R58.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Fair Value of FInancial Instruments Fair Value Unobservable Input Reconciliation (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Net realized and unrealized losses | $ 11,000,000 | $ 80,000,000 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | (1,000,000) | 0 |
Net transfers out of Level 3 to Level 2 | (10,000,000) | (61,000,000) |
Net liabilities from price risk management activities as of end of year | 119,000,000 | 119,000,000 | $ 100,000,000
Level 3 net unrealized losses that have been fully offset by the effect of regulatory accounting | 11,000,000 | 80,000,000 |
Net realized losses | $ 0 | $ 0 |

X
- Definition Level 3 net realized and unrealized losses that have been offset by the effect of regulatory accounting. + References No definition available. + Details
Name: | por_Level3RealizedAndUnrealizedLossesOffsetByEffectOfRegulatoryAccounting
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Net Liabilities From Price Risk Management Activities Classified as Level 3 + References No definition available. + Details
Name: | por_NetLiabilitiesFromPriceRiskManagementActivitiesClassifiedAsLevel3
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition net realized losses on price risk management + References No definition available. + Details
Name: | por_NetRealizedLosses
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Realized and Unrealized Gains and Losses, Net, Commodity Contracts + References No definition available. + Details
Name: | por_RealizedAndUnrealizedGainsAndLossesNetCommodityContract
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration