XML 71 R53.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Sale of First Choice (Details) (USD $) | 12 Months Ended | 0 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Sep. 23, 2011 First Choice [Member] | Dec. 31, 2012 First Choice [Member] | Dec. 31, 2012 First Choice [Member] | Dec. 31, 2012 Other Income [Member] First Choice [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |
Sale of Business Segment subject to adjustments of certain componets of working capital |  |  |  | $ 270,000,000 |  |  |
Sale of Business Segment, Amount received including estimate of components of working capital |  |  |  | 329,300,000 |  |  |
Gain on sale of First Choice | 1,012,000 | 174,925,000 | 0 |  | 174,900,000 | 174,900,000 | 1,000,000
Sale of Business Segment Working Capital That Parent Disputed, Portion of Disputed Total Awarded |  |  |  |  |  | 6,400,000 |
Sale of Business Segment Working Capital That Parent Disputed, Disputed Amount |  |  |  |  |  | $ 8,200,000 |

X
- Definition Gain on Sale of Business Segment + References No definition available. + Details
Name: | pnm_GainOnSaleOfBusinessSegment
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Sale of Business Segment, Amount received including estimate of components of working capital + References No definition available. + Details
Name: | pnm_SaleOfBusinessSegmentAmountReceivedIncludingEstimateOfComponentsOfWorkingCapital
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Sale of Business Segment subject to adjustments of certain componets of working capital + References No definition available. + Details
Name: | pnm_SaleOfBusinessSegmentSubjectToAdjustmentsOfCertainComponetsOfWorkingCapital
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Sale of Business Segment Working Capital That Parent Disputed, Disputed Amount + References No definition available. + Details
Name: | pnm_SaleOfBusinessSegmentWorkingCapitalThatParentDisputedDisputedAmount
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Sale of Business Segment Working Capital That Parent Disputed, Portion of Disputed Total Awarded + References No definition available. + Details
Name: | pnm_SaleOfBusinessSegmentWorkingCapitalThatParentDisputedPortionOfDisputedTotalAwarded
Namespace Prefix: | pnm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration