Lease Commitments Schedule of Future Minimum Rental Payments for Operating Leases (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
PNMR [Member]
Lease commitments
2013	$ 44,040
2014	52,136
2015	31,389
2016	15,790
2017	12,519
Later years	94,883
Operating Leases, Future Minimum Payments Due	250,757
Future payments under non-cancelable subleases	233
Net minimum lease payments	250,524
Public Service Company of New Mexico [Member]
Lease commitments
2013	40,217
2014	49,079
2015	29,601
2016	15,790
2017	12,519
Later years	94,883
Operating Leases, Future Minimum Payments Due	242,089
Future payments under non-cancelable subleases	0
Net minimum lease payments	242,089
Texas-New Mexico Power Company [Member]
Lease commitments
2013	481
2014	55
2015	0
2016	0
2017	0
Later years	0
Operating Leases, Future Minimum Payments Due	536
Future payments under non-cancelable subleases	0
Net minimum lease payments	$ 536

Net minimum lease payments

No definition available.

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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Contractually required future rental payments receivable on noncancelable subleasing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

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Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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