XML 70 R43.htm IDEA: XBRL DOCUMENT v3.4.0.3

Fair Value of Derivative and Other Financial Instruments - Available for Sale Securities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Other than temporary impairment losses, Investments, portion recognized in earnings, net, available-for-sale securities	$ 1,600	$ 400
PNMR and PNM [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	260,628		$ 259,042
Unrealized Gains	22,980		28,820
Proceeds from sales	124,900	31,852
Gross realized gains	10,716	5,135
Gross realized (losses)	(6,116)	$ (1,541)
PNMR and PNM [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	260,628		259,042
PNMR and PNM [Member] | Nuclear Decommissioning Trust [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	250,500		249,100
PNMR and PNM [Member] | Mine Reclamation Trust [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	10,100		9,900
PNMR and PNM [Member] | Cash and equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	8,810		10,700
Unrealized Gains	0		0
PNMR and PNM [Member] | Cash and equivalents [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	8,810		10,700
PNMR and PNM [Member] | Domestic value [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	62,427		44,505
Unrealized Gains	10,862		11,610
PNMR and PNM [Member] | Domestic value [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	62,427		44,505
PNMR and PNM [Member] | Domestic growth [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	43,714		61,078
Unrealized Gains	5,164		11,163
PNMR and PNM [Member] | Domestic growth [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	43,714		61,078
PNMR and PNM [Member] | International and other [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	27,937		27,961
Unrealized Gains	2,034		1,569
PNMR and PNM [Member] | International and other [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	27,937		27,961
PNMR and PNM [Member] | U.S. Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	37,203		27,880
Unrealized Gains	563		178
PNMR and PNM [Member] | U.S. Government [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	37,203		27,880
PNMR and PNM [Member] | Municipals [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	50,276		58,576
Unrealized Gains	2,839		3,672
PNMR and PNM [Member] | Municipals [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	50,276		58,576
PNMR and PNM [Member] | Corporate and other [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	30,261		28,342
Unrealized Gains	1,518		628
PNMR and PNM [Member] | Corporate and other [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	$ 30,261		$ 28,342

X

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

+ Details

Name:	us-gaap_AvailableForSaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesGrossRealizedGains
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

+ Details

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

X

- Definition

The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

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

X

- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

+ Details

Name:	us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	dei_LegalEntityAxis=pnm_PnmrAndPnmMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=pnm_NuclearDecommissioningTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=pnm_MineReclamationTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CashAndCashEquivalentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=pnm_DomesticValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=pnm_DomesticGrowthMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=pnm_MultinationalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MunicipalBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_OtherDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: