Gain on Sale of Business Segment

No definition available.

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- Definition

Aggregate revenues less cost of energy

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No definition available.

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- Definition

Other Income Deductions Excluding Interest

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No definition available.

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- Definition

Other Operating Expenses

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No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Total costs related to electricity produced and sold during the reporting period.

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-Subparagraph (SX 210.5-03.2(b))

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- Definition

Depreciation of property, plant and equipment directly related to services rendered by an entity during the reporting period.

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- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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- Definition

The aggregate revenue, whether regulated or unregulated, derived from the generation, transmission and distribution of electricity.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

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.

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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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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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- Definition

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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-Glossary Investing Activities

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information, Profit (Loss) [Abstract]
Electric Operating Revenues	$ 346,845us-gaap_ElectricUtilityRevenue	$ 413,951us-gaap_ElectricUtilityRevenue	$ 346,160us-gaap_ElectricUtilityRevenue	$ 328,897us-gaap_ElectricUtilityRevenue	$ 322,929us-gaap_ElectricUtilityRevenue	$ 399,730us-gaap_ElectricUtilityRevenue	$ 347,599us-gaap_ElectricUtilityRevenue	$ 317,665us-gaap_ElectricUtilityRevenue	$ 1,435,853us-gaap_ElectricUtilityRevenue	$ 1,387,923us-gaap_ElectricUtilityRevenue	$ 1,342,403us-gaap_ElectricUtilityRevenue
Cost of energy									471,556us-gaap_CostOfGoodsSoldElectric	432,316us-gaap_CostOfGoodsSoldElectric	399,850us-gaap_CostOfGoodsSoldElectric
Margin									964,297pnm_GrossMargin	955,607pnm_GrossMargin	942,553pnm_GrossMargin
Other operating expenses									491,966pnm_OtherOperatingExpenses	501,884pnm_OtherOperatingExpenses	504,659pnm_OtherOperatingExpenses
Depreciation and amortization									172,634	166,881	164,173
Operating income	62,849us-gaap_OperatingIncomeLoss	116,799us-gaap_OperatingIncomeLoss	71,296us-gaap_OperatingIncomeLoss	48,753us-gaap_OperatingIncomeLoss	40,532us-gaap_OperatingIncomeLoss	117,739us-gaap_OperatingIncomeLoss	77,867us-gaap_OperatingIncomeLoss	50,704us-gaap_OperatingIncomeLoss	299,697us-gaap_OperatingIncomeLoss	286,842us-gaap_OperatingIncomeLoss	273,721us-gaap_OperatingIncomeLoss
Interest income									8,483us-gaap_InvestmentIncomeInterest	10,043us-gaap_InvestmentIncomeInterest	13,072us-gaap_InvestmentIncomeInterest
Gain on sale of First Choice									0pnm_GainOnSaleOfBusinessSegment	0pnm_GainOnSaleOfBusinessSegment	1,012pnm_GainOnSaleOfBusinessSegment
Other income (deductions)									12,094	(368)	8,075
Interest charges									(119,627)us-gaap_InterestExpense	(121,448)us-gaap_InterestExpense	(120,845)us-gaap_InterestExpense
Earnings before Income Taxes									200,647	175,069	175,035
Income Taxes									69,738us-gaap_IncomeTaxExpenseBenefit	59,513us-gaap_IncomeTaxExpenseBenefit	54,910us-gaap_IncomeTaxExpenseBenefit
Net Earnings	22,111us-gaap_ProfitLoss	59,486us-gaap_ProfitLoss	33,181us-gaap_ProfitLoss	16,131us-gaap_ProfitLoss	11,397us-gaap_ProfitLoss	58,814us-gaap_ProfitLoss	31,383us-gaap_ProfitLoss	13,962us-gaap_ProfitLoss	130,909us-gaap_ProfitLoss	115,556us-gaap_ProfitLoss	120,125us-gaap_ProfitLoss
Valencia non-controlling interest									(14,127)	(14,521)	(14,050)
Preferred Stock Dividend Requirements of Subsidiary									(528)us-gaap_DividendsPreferredStock	(528)us-gaap_DividendsPreferredStock	(528)us-gaap_DividendsPreferredStock
Segment earnings (loss) attributable to PNMR									116,254	100,507	105,547
Gross property additions									460,658	348,039	308,909
Total Assets	5,829,325us-gaap_Assets				5,500,210us-gaap_Assets				5,829,325us-gaap_Assets	5,500,210us-gaap_Assets	5,372,583us-gaap_Assets
Goodwill	278,297us-gaap_Goodwill				278,297us-gaap_Goodwill				278,297us-gaap_Goodwill	278,297us-gaap_Goodwill	278,297us-gaap_Goodwill
PNM [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Electric Operating Revenues									1,147,914	1,116,312	1,092,264
Cost of energy									403,626	374,710	353,649
Margin									744,288	741,602	738,615
Other operating expenses									422,051	428,591	435,442
Depreciation and amortization									109,524	103,826	97,291
Operating income									212,713	209,185	205,882
Interest income									8,557	10,182	13,243
Gain on sale of First Choice											0
Other income (deductions)									12,258	11,288	13,290
Interest charges									(79,442)	(79,175)	(76,101)
Earnings before Income Taxes									154,086	151,480	156,314
Income Taxes									52,633	48,804	50,713
Net Earnings									101,453	102,676	105,601
Valencia non-controlling interest									(14,127)	(14,521)	(14,050)
Preferred Stock Dividend Requirements of Subsidiary									(528)	(528)	(528)
Segment earnings (loss) attributable to PNMR									86,798	87,627	91,023
Gross property additions									316,800	239,906	196,800
Total Assets	4,473,652				4,227,616				4,473,652	4,227,616	4,163,907
Goodwill	51,632				51,632				51,632	51,632	51,632
TNMP [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Electric Operating Revenues									287,939	271,611	250,140
Cost of energy									67,930	57,606	46,201
Margin									220,009	214,005	203,939
Other operating expenses									84,365	91,601	87,079
Depreciation and amortization									50,056	50,219	49,340
Operating income									85,588	72,185	67,520
Interest income									0	0	1
Gain on sale of First Choice											0
Other income (deductions)									2,138	1,919	2,739
Interest charges									(27,396)	(27,393)	(28,161)
Earnings before Income Taxes									60,330	46,711	42,099
Income Taxes									22,523	17,621	15,352
Net Earnings									37,807	29,090	26,747
Valencia non-controlling interest									0	0	0
Preferred Stock Dividend Requirements of Subsidiary									0	0	0
Segment earnings (loss) attributable to PNMR									37,807	29,090	26,747
Gross property additions									127,191	89,117	92,973
Total Assets	1,240,241				1,162,431				1,240,241	1,162,431	1,086,229
Goodwill	226,665				226,665				226,665	226,665	226,665
Corporate and Other [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Electric Operating Revenues									0	0	(1)
Cost of energy									0	0	0
Margin									0	0	(1)
Other operating expenses									(14,450)	(18,308)	(17,862)
Depreciation and amortization									13,054	12,836	17,542
Operating income									1,396	5,472	319
Interest income									(74)	(139)	(172)
Gain on sale of First Choice											1,012
Other income (deductions)									(2,302)	(13,575)	(7,954)
Interest charges									(12,789)	(14,880)	(16,583)
Earnings before Income Taxes									(13,769)	(23,122)	(23,378)
Income Taxes									(5,418)	(6,912)	(11,155)
Net Earnings									(8,351)	(16,210)	(12,223)
Valencia non-controlling interest									0	0	0
Preferred Stock Dividend Requirements of Subsidiary									0	0	0
Segment earnings (loss) attributable to PNMR									(8,351)	(16,210)	(12,223)
Gross property additions									16,667	19,016	19,136
Total Assets	115,432				110,163				115,432	110,163	122,447
Goodwill	$ 0				$ 0				$ 0	$ 0	$ 0