Acquisitions and Dispositions	12 Months Ended
Dec. 31, 2011
Business Combinations [Abstract]
Acquisitions and Dispositions	Acquisitions and Dispositions Sale of First Choice On September 23, 2011, PNMR entered into an agreement for the sale of First Choice to Direct LP, Inc. for $270.0 million, subject to adjustment to reflect the actual amounts of certain components of working capital at closing. Closing occurred on November 1, 2011, with PNMR receiving $329.3 million, which includes an estimate of the components of working capital. For accounting purposes, the sale was effective as of the close of business on October 31, 2011. Such amount is subject to adjustment based on the actual amounts of the components of working capital at October 31, 2011. PNMR recognized a pre-tax gain of $174.9 million on the sale. The purchaser has informed PNMR that it believes working capital at October 31, 2011 was overstated by $4.2 million. PNMR has responded to the purchaser disputing the purchaser's calculation and indicating that working capital at October 31, 2011 was understated by $6.5 million. PNMR believes its calculation is consistent with the terms of the agreement. PNMR does not believe the ultimate resolution of this matter will have a material impact. PNMR used the net proceeds from the sale of First Choice to repurchase certain of PNMR's outstanding debt and equity securities (Note 6) and for other corporate purposes, including repayment of borrowings under the PNMR Revolving Credit Facility. PNMR Services Company will continue to provide certain services at cost to First Choice for a transitional period of up to nine months following closing. Because PNMR will continue to have direct cash flows resulting from transmission and distribution services provided by TNMP to First Choice, First Choice is not reflected as discontinued operations. After October 31, 2011, TNMP's revenues from First Choice are not intercompany and are not eliminated in consolidation by PNMR. Sale of PNM Gas In January 2008, PNM reached a definitive agreement to sell its natural gas operations, which comprised the PNM Gas segment, to NMGC, a subsidiary of Continental, for $620.0 million in cash, subject to adjustment based on the actual level of working capital at closing. See Note 22 for financial information concerning PNM Gas, which is classified as discontinued operations in the accompanying financial statements. In a separate transaction conditioned upon the sale of the natural gas operations, PNMR proposed to acquire CRHC, Continental’s regulated Texas electric transmission and distribution business. In July 2008, PNMR and Continental agreed to terminate the CRHC agreement and Continental agreed to pay PNMR $15.0 million upon the closing of the PNM Gas transaction. PNM completed the sale of PNM Gas on January 30, 2009 and recognized a gain of $65.3 million, after income taxes of $33.1 million, which reflects PNM receiving $32.9 million related to working capital true-ups. This gain also reflects the reduction for the increase in the PBO of the PNM pension plan related to the retirement of employees transferred to NMGC. See Note 12. In 2009, PNMR recognized an additional pre-tax gain of $15.0 million ($9.1 million after income taxes) due to the CRHC termination payment, which is included in other income on the Consolidated Statements of Earnings (Loss). In connection with the sale, PNM retained obligations under the frozen PNM pension and executive retirement plans for employees transferred to NMGC. PNM had a regulatory asset related to these plans, which was removed from regulatory assets on the date of the sale and transferred to AOCI. The after-tax charge to AOCI was $64.8 million. PNM also retained obligations for certain contingent liabilities that existed at the date of sale and recognized $5.4 million in expense related to these liabilities in 2009. PNM used the after-tax proceeds from the sale to retire short-term debt and paid a dividend of $220.0 million to PNMR. PNMR used the dividend from PNM and the $15.0 million from Continental to retire debt. Other In June 2007, a wholly-owned subsidiary of PNMR purchased 100% of a trust that owns a 2.27% undivided interest, representing 29.8 MW, in PVNGS Unit 2, as well as a lease under which such facilities are leased to PNM. The Resource Stipulation described in Note 17 allowed the Unit 2 interest to be transferred to PNM and the acquisition costs to be recovered in PNM’s rates beginning with the 2008 Electric Rate Case. In July 2009, PNM purchased the trust from the other PNMR subsidiary for $39.1 million in cash. The purchase price was equal to the book value of the underlying assets less deferred taxes and miscellaneous accruals. The other PNMR subsidiary paid a dividend of that same amount to PNMR. PNMR then made an equity contribution of that amount to PNM. The trust had $32.0 million of debt owing to the PVNGS Capital Trust, which is consolidated by PNM.

Acquisitions and Dispositions

Sale of First Choice

On September 23, 2011, PNMR entered into an agreement for the sale of First Choice to Direct LP, Inc. for $270.0 million, subject to adjustment to reflect the actual amounts of certain components of working capital at closing. Closing occurred on November 1, 2011, with PNMR receiving $329.3 million, which includes an estimate of the components of working capital. For accounting purposes, the sale was effective as of the close of business on October 31, 2011. Such amount is subject to adjustment based on the actual amounts of the components of working capital at October 31, 2011. PNMR recognized a pre-tax gain of $174.9 million on the sale. The purchaser has informed PNMR that it believes working capital at October 31, 2011 was overstated by $4.2 million. PNMR has responded to the purchaser disputing the purchaser's calculation and indicating that working capital at October 31, 2011 was understated by $6.5 million. PNMR believes its calculation is consistent with the terms of the agreement. PNMR does not believe the ultimate resolution of this matter will have a material impact. PNMR used the net proceeds from the sale of First Choice to repurchase certain of PNMR's outstanding debt and equity securities (Note 6) and for other corporate purposes, including repayment of borrowings under the PNMR Revolving Credit Facility. PNMR Services Company will continue to provide certain services at cost to First Choice for a transitional period of up to nine months following closing. Because PNMR will continue to have direct cash flows resulting from transmission and distribution services provided by TNMP to First Choice, First Choice is not reflected as discontinued operations. After October 31, 2011, TNMP's revenues from First Choice are not intercompany and are not eliminated in consolidation by PNMR.

Sale of PNM Gas

In January 2008, PNM reached a definitive agreement to sell its natural gas operations, which comprised the PNM Gas segment, to NMGC, a subsidiary of Continental, for $620.0 million in cash, subject to adjustment based on the actual level of working capital at closing. See Note 22 for financial information concerning PNM Gas, which is classified as discontinued operations in the accompanying financial statements. In a separate transaction conditioned upon the sale of the natural gas operations, PNMR proposed to acquire CRHC, Continental’s regulated Texas electric transmission and distribution business. In July 2008, PNMR and Continental agreed to terminate the CRHC agreement and Continental agreed to pay PNMR $15.0 million upon the closing of the PNM Gas transaction. PNM completed the sale of PNM Gas on January 30, 2009 and recognized a gain of $65.3 million, after income taxes of $33.1 million, which reflects PNM receiving $32.9 million related to working capital true-ups. This gain also reflects the reduction for the increase in the PBO of the PNM pension plan related to the retirement of employees transferred to NMGC. See Note 12. In 2009, PNMR recognized an additional pre-tax gain of $15.0 million ($9.1 million after income taxes) due to the CRHC termination payment, which is included in other income on the Consolidated Statements of Earnings (Loss). In connection with the sale, PNM retained obligations under the frozen PNM pension and executive retirement plans for employees transferred to NMGC. PNM had a regulatory asset related to these plans, which was removed from regulatory assets on the date of the sale and transferred to AOCI. The after-tax charge to AOCI was $64.8 million. PNM also retained obligations for certain contingent liabilities that existed at the date of sale and recognized $5.4 million in expense related to these liabilities in 2009. PNM used the after-tax proceeds from the sale to retire short-term debt and paid a dividend of $220.0 million to PNMR. PNMR used the dividend from PNM and the $15.0 million from Continental to retire debt.

Other

In June 2007, a wholly-owned subsidiary of PNMR purchased 100% of a trust that owns a 2.27% undivided interest, representing 29.8 MW, in PVNGS Unit 2, as well as a lease under which such facilities are leased to PNM. The Resource Stipulation described in Note 17 allowed the Unit 2 interest to be transferred to PNM and the acquisition costs to be recovered in PNM’s rates beginning with the 2008 Electric Rate Case. In July 2009, PNM purchased the trust from the other PNMR subsidiary for $39.1 million in cash. The purchase price was equal to the book value of the underlying assets less deferred taxes and miscellaneous accruals. The other PNMR subsidiary paid a dividend of that same amount to PNMR. PNMR then made an equity contribution of that amount to PNM. The trust had $32.0 million of debt owing to the PVNGS Capital Trust, which is consolidated by PNM.